A5037193371- Radiation Therapy and Dosimetry
- Advanced Radiotherapy Techniques
- Advances in Oncology and Radiotherapy
- Radiation Detection and Scintillator Technologies
- Medical Imaging Techniques and Applications
- DNA and Nucleic Acid Chemistry
- Radiation Effects in Electronics
- DNA Repair Mechanisms
- Particle Detector Development and Performance
- Advanced X-ray and CT Imaging
- Particle accelerators and beam dynamics
- Radiation Dose and Imaging
- Carcinogens and Genotoxicity Assessment
- Economic and Financial Impacts of Cancer
- Advanced MRI Techniques and Applications
- RNA modifications and cancer
- Global Health and Surgery
- Epigenetics and DNA Methylation
- Lung Cancer Diagnosis and Treatment
- Nuclear Physics and Applications
- RNA and protein synthesis mechanisms
- Health Systems, Economic Evaluations, Quality of Life
- Radiomics and Machine Learning in Medical Imaging
- Boron Compounds in Chemistry
- Chemical Reactions and Isotopes
European Organization for Nuclear Research
2016-2025
University of Oxford
2020-2025
University of Victoria
2024
International Medical Corps
2018-2022
National Space Agency
2020
Malaysian Nuclear Agency
2020
National Cancer Institute
2017
University of British Columbia
2016-2017
Technische Universität Dresden
2016
University of Lausanne
2016
In this article the Tomographic Iterative GPU-based Reconstruction (TIGRE) Toolbox, a MATLAB/CUDA toolbox for fast and accurate 3D x-ray image reconstruction, is presented. One of key features implementation wide variety iterative algorithms as well FDK, including range in SART family, Krylov subspace family methods using total variation regularization. Additionally, has GPU-accelerated projection back latest techniques it modular design that facilitates new algorithms. We present an...
As carbon ions, at therapeutic energies, penetrate tissue, they undergo inelastic nuclear reactions and give rise to significant yields of secondary fragment fluences. Therefore, an accurate prediction these fluences resulting from the primary interactions is necessary in patient's body order precisely simulate spatial dose distribution biological effect. In this paper, performance fragmentation models Monte Carlo transport codes, FLUKA GEANT4, tissue-like media for energy regime relevant...
The yeast and human RAD51 genes encode strand-transfer proteins that are thought to be involved in both recombinational repair of DNA damage meiotic recombination. In yeast, the Rad51 family related also includes Rad55, Rad57 Dmc1. mammalian cells, five this have been identified (HsRAD51, XRCC2, XRCC3, RAD51B/hREC2 HsDMC1), here we report isolation sixth member, RAD51C. RAD51C was originally by a computer screen EST database. A full-length approximately 1.3 kb cDNA clone has isolated encodes...
We have previously reported that human cells and tissues contain a 1,N6-ethenoadenine (epsilon A) binding protein, which, through glycosylase activity, releases both 3-methyladenine (m3A) epsilon A from DNA treated with methylating agents or the vinyl chloride metabolite chloroacetaldehyde, respectively. now find partially purified A-binding protein cell-free extracts containing cloned m3A-DNA release all four cyclic etheno adducts--namely A, 3,N4-ethenocytosine C), N2,3-ethenoguanine...
Vinyl chloride is a known human and rodent carcinogen that forms several cyclic base derivatives in DNA. The mutagenic potential of these has been examined vitro but not vivo. One derivatives, N2,3-ethenoguanine (epsilon G), to pair with both cytosine thymine during DNA synthesis, which would result G----A transitions. To determine the pairing specificity this labile guanine derivative Escherichia coli, we have developed genetic reversion assay for derivatives. utilizes polymerase-mediated...
O6-Methylguanine (m6G) was incorporated site-specifically into two 25-base oligonucleotides differing only in the nucleotide on 3' side of modified base. Templates were primed with terminating one or bases prior to site at which incorporation kinetics be investigated. Escherichia coli DNA polymerase I (Klenow fragment) used determine apparent Km and relative Vmax either dCTP dTTP opposite m6G G. These data calculate frequency unmodified When sequence 3'-Cm6G-5', there a 6- 7-fold preference...
Very high energy electron (VHEE) beams with energies greater than 100 MeV may be promising candidates for FLASH radiotherapy due to their favourable dose distributions and accessibility of ultrahigh dose-rates (UHDR). Combining VHEE the normal tissue-sparing effect UHDR could improve patient outcomes. The standard dosimeters used conventional radiotherapy, including ionization chambers film, have limited application deficits in rate independence temporal resolution. Plastic scintillator...
N2, 3-Ethenoguanine (εG) is a product of vinyl chloride reaction with DNA in vivo and its ultimate metabolite, chloroacetaldehyde, vitro. The synthesis the very labile 5′-triphosphate N2,3-etheno-deoxyguanosine (εdGuo) has made it possible to study base pairing properties this derivative placed opposite defined normal 25-base oligonucleotide template. kinetic parameters, Km Vmax were determined from elongation [32P]5′-end labeled primer annealed one prior designated template base. εG⋅T...
We previously described a protein, isolated from human tissues and cells, that bound to defined double-stranded oligonucleotide containing single site-specifically placed 1,N6-ethenoadenine. It was further demonstrated this protein glycosylase released now find enzyme also releases 3-methyladenine methylated DNA 3-methyladenine-DNA behaves in the same manner, binding ethenoadenine-containing cleaving both ethenoadenine these adducts. The rate extent of activities toward two adducts are similar.
The suicidal inactivation mechanism of DNA repair methyltransferases (MTases) was exploited to measure the relative efficiencies with which Escherichia coli, human, and Saccharomyces cerevisiae MTases O6-methylguanine (O6MeG) O4-methylthymine (O4MeT), two lesions produced by mutagenic carcinogenic alkylating agents. Using chemically synthesized double-stranded 25-base pair oligodeoxynucleotides containing a single O6MeG or O4MeT, concentration O4MeT substrate that 50% (IC50) determined for...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXT1,N6-Ethenoadenine Is Preferred over 3-Methyladenine as Substrate by a Cloned Human N-Methylpurine-DNA Glycosylase (3-Methyladenine-DNA Glycosylase)M. K. Dosanjh, R. Roy, S. Mitra, and B. SingerCite this: Biochemistry 1994, 33, 7, 1624–1628Publication Date (Print):February 22, 1994Publication History Published online1 May 2002Published inissue 22 February...
Uncertainties in determining clinically used relative biological effectiveness (RBE) values for ion beam therapy carry the risk of absolute and misestimations RBE-weighted doses clinical scenarios. This study assesses consequences hypothetical input parameters to RBE modelling carbon treatment plans by a variational approach. The impact variations on resulting cell survival is evaluated as function remaining range. In addition, sensitivity compared single fields two opposed using differing...
Spatially-fractionated radiotherapy (SFRT) delivered with a very-high-energy electron (VHEE) beam and mini-GRID collimator was investigated to achieve synergistic normal tissue-sparing through spatial fractionation the FLASH effect.
The frequency of extending m6G.C or m6G.T pairs, when the 3' and 5' flanking neighbors m6G are either cytosines thymines, was investigated using primed 25-base-long oligonucleotides Klenow fragment Escherichia coli DNA polymerase I (Kf). efficiency, Vmax/Km, extension to following normal base pair up 40-fold greater than for formation pair. frequencies inserting dCMP dTMP opposite these bases did not appear be different in two sequences, C-m6G-C T-m6G-T, but favored sequence. extended a C.G...
Ion beam therapy, as an emerging radiation therapy modality, requires continuous efforts to develop and improve tools for patient treatment planning (TP) research applications. Dose fluence computation algorithms using the Monte Carlo (MC) technique have served decades reference accurate dose computations radiotherapy. In this work, a novel MC-based treatment-planning (MCTP) tool ion pencil scanning is presented. It allows single-field simultaneous multiple-fields optimization realistic...
Treatment standard for patients with rectal cancer depends on the initial staging and includes surgical resection, radiotherapy as well chemotherapy. For stage II III tumors, radiochemotherapy should be performed in addition to surgery, preferentially preoperative or short-course hypofractionated radiation. Advances approaches, especially establishment of total mesorectal excision (TME) combination sophisticated radiation chemotherapy have reduced local recurrence rates only few percent....
PURPOSE Access to radiotherapy (RT) is now one of the stark examples global cancer inequities. More than 800,000 new cases require potentially curative or palliative RT services in Africa, arguably <15% these patients currently have access this important service. For a population more 206 million, Nigeria requires minimum 280 machines for increasing number cases. Painfully, country has only eight Government-funded machines. This study aimed evaluate status and their ability deliver...
Abstract Objective . Very high energy electrons (VHEE) in the range of 50–250 MeV are interest for treating deep-seated tumours with FLASH radiotherapy (RT). This approach offers favourable dose distributions and ability to deliver ultra-high rates (UHDR) efficiently. To make VHEE-based treatment clinically viable, a novel beam monitoring technology is explored as an alternative transmission ionisation monitor chambers, which have non-linear responses at UHDR. study introduces fibre optic...