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1.
RNA Biol ; 12(8): 771-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26259533

RESUMEN

Over the past 10 years, it has emerged that pervasive transcription in mammalian genomes has a tremendous impact on several biological functions. Most of transcribed RNAs are lncRNAs and repetitive elements. In this review, we will detail the discovery of a new functional class of natural and synthetic antisense lncRNAs that stimulate translation of sense mRNAs. These molecules have been named SINEUPs since their function requires the activity of an embedded inverted SINEB2 sequence to UP-regulate translation. Natural SINEUPs suggest that embedded Transposable Elements may represent functional domains in long non-coding RNAs. Synthetic SINEUPs may be designed by targeting the antisense sequence to the mRNA of choice representing the first scalable tool to increase protein synthesis of potentially any gene of interest. We will discuss potential applications of SINEUP technology in the field of molecular biology experiments, in protein manufacturing as well as in therapy of haploinsufficiencies.


Asunto(s)
Biosíntesis de Proteínas , ARN sin Sentido/genética , ARN Largo no Codificante/genética , ARN Mensajero/genética , Animales , Sitios de Unión/genética , Humanos , Modelos Genéticos , ARN sin Sentido/metabolismo , ARN Largo no Codificante/metabolismo , ARN Mensajero/metabolismo , Secuencias Repetitivas de Ácidos Nucleicos/genética
2.
Phys Med Biol ; 50(18): 4287-97, 2005 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-16148394

RESUMEN

A passive system for neutron spectrometry has been tested in view of neutron dose evaluation in mixed radiation fields. This system, based on bubble detectors (Bubble Technology Industries, Ontario, Canada), is suitable to evaluate the neutron energy distribution in the range 10 keV-20 MeV even in the presence of intense gamma radiation, as required in various fields: medical x-ray accelerators, nuclear reactors, cosmic ray exposures on commercial high-altitude flights and space missions. A new unfolding code BUNTO has been especially developed for this application. In the present work, the results of two experimental tests are summarized. In the first one, the device has been exposed to a standard AmBe neutron source (Joint Research Centre, Ispra, Varese, Italy). In the second one, measurements have been carried out at the MAX-Lab photonuclear facility in Sweden, with a bremsstrahlung photon beam impinging on thick targets of different materials and generating a giant dipole resonance neutron spectrum. Simulations of the experimental apparatus have been performed with MCNP4B (AmBe source) and with MCNP4B-GN (MAX-Lab). Results of the comparison between experimental and calculated spectra are shown and discussed. A good agreement between measurements and simulation data is obtained in both the experiments.


Asunto(s)
Neutrones , Radiometría/instrumentación , Radiometría/métodos , Espectrofotometría/métodos , Modelos Estadísticos , Método de Montecarlo , Fantasmas de Imagen , Fotones , Dosis de Radiación , Monitoreo de Radiación , Programas Informáticos , Espectrofotometría/instrumentación
3.
Radiat Prot Dosimetry ; 110(1-4): 157-60, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15353639

RESUMEN

Bremsstrahlung photon beams produced by LINAC accelerators are currently the most used radiotherapy method for tumour treatments. When the photon energy exceeds the (gamma,n) reaction threshold energy, the patient receives an undesired dose due to photoneutron production both in the accelerator head and in the human body. In this paper, a method is presented for the assessment of the photoneutron spectra produced by Giant Dipole Resonance (GDR) during cancer radiotherapy with energetic photon beams. Experimental and numerical results have been obtained for the facility at Onkologik Klinik, Lund (Sweden), which is based on an ELEKTA 18 MV LINAC. Neutron spectra are evaluated both at the patient plane and inside an anthropomorphic phantom.


Asunto(s)
Neoplasias/radioterapia , Neutrones/efectos adversos , Aceleradores de Partículas/instrumentación , Fantasmas de Imagen , Radiometría/instrumentación , Planificación de la Radioterapia Asistida por Computador/instrumentación , Análisis Espectral/instrumentación , Simulación por Computador , Humanos , Modelos Biológicos , Modelos Estadísticos , Método de Montecarlo , Traumatismos por Radiación/etiología , Traumatismos por Radiación/prevención & control , Protección Radiológica/instrumentación , Protección Radiológica/métodos , Radiometría/métodos , Radioterapia/instrumentación , Radioterapia/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Análisis Espectral/métodos
4.
Radiat Prot Dosimetry ; 110(1-4): 651-4, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15353725

RESUMEN

Dosimetry and spectrometry measurements have been carried out in the thermal column of the research fast reactor RSV-TAPIRO (ENEA-Casaccia, Rome) in order to investigate its suitability for irradiation of cells or mice, with a view to research in the interests of boron neutron capture therapy (BNCT). The thermal column consists of a graphite moderator (40 cm thick) containing a lead shield (13 cm thick) in order to shield reactor background. The irradiation volume, inside this structure, has cubic shape (18 x 18 x 18 cm3). Besides measurements of fluence and dose rates in air or in phantom performed with thermoluminescence dosemeters (TLDs) and using the activation technique, dose and fluence profiles have been generated using a method based on gel dosemeters analysed with optical imaging. To check the consistency of the results, spectrometry measurements in the same irradiation volume have been performed by means of bubble detectors.


Asunto(s)
Terapia por Captura de Neutrón de Boro/instrumentación , Análisis de Falla de Equipo/métodos , Neutrones/uso terapéutico , Protección Radiológica/instrumentación , Radiometría/métodos , Planificación de la Radioterapia Asistida por Computador/instrumentación , Animales , Carga Corporal (Radioterapia) , Terapia por Captura de Neutrón de Boro/métodos , Diseño de Equipo , Rayos gamma/uso terapéutico , Calor , Humanos , Italia , Reactores Nucleares , Radiobiología/instrumentación , Radiometría/instrumentación , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Efectividad Biológica Relativa , Reproducibilidad de los Resultados , Medición de Riesgo/métodos , Sensibilidad y Especificidad
5.
Phys Med Biol ; 49(4): 571-82, 2004 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-15005166

RESUMEN

Bremsstrahlung photon beams produced by linac accelerators are currently the most commonly used method of radiotherapy for tumour treatments. When the photon energy exceeds 10 MeV the patient receives an undesired dose due to photoneutron production in the accelerator head. In the last few decades, new sophisticated techniques such as multileaf collimators have been used for a better definition of the target volume. In this case it is crucial to evaluate the photoneutron dose produced after giant dipole resonance (GDR) excitation of the high Z materials (mainly tungsten and lead) constituting the collimator leaves in view of the optimization of the radiotherapy treatment. A Monte Carlo approach has been used to calculate the photoneutron dose arising from the GDR reaction during radiotherapy with energetic photon beams. The simulation has been performed using the code MCNP4B-GN which is based on MCNP4B, but includes a new routine GAMMAN to model photoneutron production. Results for the facility at IRCC (Istituto per la Ricerca e la Cura del Cancro) Candiolo (Turin), which is based on 18 MV x-rays from a Varian Clinac 2300 C/D, are presented for a variety of different collimator configurations.


Asunto(s)
Método de Montecarlo , Neoplasias/radioterapia , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Alta Energía , Humanos , Masculino , Neutrones , Aceleradores de Partículas/instrumentación , Fotones , Próstata/diagnóstico por imagen , Radiografía
6.
Phys Med Biol ; 48(20): 3345-52, 2003 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-14620062

RESUMEN

Photoneutron production on the nuclei of high-Z components of medical accelerator heads can lead to a significant secondary dose during a course of bremsstrahlung radiotherapy. However, a quantitative evaluation of secondary neutron dose requires improved data on the photoreaction yields. These have been measured as a function of photon energy, neutron energy and neutron angle for natW, using tagged photons at the MAX-Lab photonuclear facility in Sweden. This work presents neutron yields for natW(gamma, n) and compares these with the predictions of the Monte Carlo code MCNP-GN, developed specifically to simulate photoneutron production at medical accelerators.


Asunto(s)
Neutrones , Fotones , Radioterapia de Alta Energía , Tungsteno/efectos de la radiación , Método de Montecarlo , Dosificación Radioterapéutica , Radioterapia de Alta Energía/métodos , Programas Informáticos
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