Preclinical radiotherapy at the Australian Synchrotron's Imaging and Medical Beamline: instrumentation, dosimetry and a small-animal feasibility study

Therapeutic applications of synchrotron X-rays such as microbeam (MRT) and minibeam (MBRT) radiation therapy promise significant advantages over conventional clinical techniques for some diseases if successfully transferred to clinical practice. Preclinical studies show clear evidence that a number of normal tissues in animal models display a tolerance to much higher doses from MRT compared with conventional radiotherapy. However, a wide spread in the parameters studied makes it difficult to make any conclusions about the associated tumour control or normal tissue complication probabilities. To facilitate more systematic and reproducible preclinical synchrotron radiotherapy studies, a dedicated preclinical station including small-animal irradiation stage was designed and installed at the Imaging and Medical Beamline (IMBL) at the Australian Synchrotron. The stage was characterized in terms of the accuracy and reliability of the vertical scanning speed, as this is the key variable in dose delivery. The measured speed was found to be within 1% of the nominal speed for the range of speeds measured by an interferometer. Furthermore, dose measurements confirm the expected relationship between speed and dose and show that the measured dose is independent of the scan direction. Important dosimetric parameters such as peak dose, valley dose, the collimator output factor and peak-to-valley dose ratio are presented for 5   mm × 5   mm, 10   mm × 10   mm and 20   m...
Source: Journal of Synchrotron Radiation - Category: Physics Authors: Tags: radiotherapy preclinical dosimetry imaging research papers Source Type: research

Related Links:

Publication date: Available online 11 November 2019Source: International Journal of PharmaceuticsAuthor(s): Anirban Jana, Pankhuri Narula, Archana Chugh, Ritu KulshreshthaAbstractThe levels of microRNAs (miRNAs) are altered in various diseases including glioblastoma (GBM) and this alteration may have widespread effects on various hallmarks of cancer cells. MiR210 is overexpressed in GBM and functions as an oncogenic miRNA. Anti-miR210 therapy holds great promise but its efficient delivery remains a major challenge. Our work here explores a novel role of Tachyplesin (Tpl), a cell-penetrating antimicrobial peptide, as a nano...
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research
In this study, a novel established regulatory way of LINC00174/miR-138-5p/SOX9 axis was systematica lly studied, which may provide a new manner for glioma therapy.
Source: Human Cell - Category: Cytology Source Type: research
Gap junctional intercellular communication (GJIC) composed of connexin proteins is considered vital to cancer onset and progression since 50 years ago based on Lowenstein and Kano's works, however altered expression of connexins is still a lesser known “hallmark” of cancer. Although many studies support the hypothesis that connexins are tumor suppressors, recent evidence indicates that, in some tumor types including glioma, they may play contradictory role in some specific stages of tumor progression. We thus conduct a meta-analysis to evaluate the prognostic role of Cx43 in glioma for the unanswered questions ...
Source: Frontiers in Oncology - Category: Cancer & Oncology Source Type: research
Contributors : Ya Gao ; Yifan Zhang ; Qingfeng LiSeries Type : Expression profiling by high throughput sequencingOrganism : Homo sapiensLeucine-rich-alpha-2-glycoprotein1 (LRG1), a highly conserved member of the leucine-rich repeat family of proteins, has been reported to be involved in several tumors. Previous studies showed that it has great importance in epithelial –mesenchymal transition in colorectal cancer and could promote glioma cell lines invasion and migration. Despite the intimate relationships between LRG1 and migration in cancer research, its role in wound repair or re-epithelialization has not been unco...
Source: GEO: Gene Expression Omnibus - Category: Genetics & Stem Cells Tags: Expression profiling by high throughput sequencing Homo sapiens Source Type: research
Abstract Circular RNAs belong to a new category of non-coding RNAs, characterised by a circular structure, conservation, stability and high expression in eukaryotes. They often show tissue- or cell-specific expression. Here, we identified a testis-enriched circular RNA (circRNA), circular Bbs9 (circ-Bbs9) that is highly expressed in mouse testis. An RNase R treatment experiment confirmed that circ-Bbs9 is indeed a circRNA. In situ hybridisation experiments showed that circ-Bbs9 is expressed in Leydig cells along seminiferous tubules and in the cytoplasm of the TM3 Leydig cell line. Knocking down the circ-Bbs9 in T...
Source: Reproduction, Fertility, and Development - Category: Reproduction Medicine Authors: Tags: Reprod Fertil Dev Source Type: research
Daria Riva Neurofibromatosis type-1 (NF1) is a monogenic tumor-predisposition syndrome creating a wide variety of cognitive and behavioral abnormalities, such as decrease in cognitive functioning, deficits in visuospatial processing, attention, and social functioning. NF1 patients are at risk to develop neurofibromas and other tumors, such as optic pathway gliomas and other tumors of the central nervous system. Few studies have investigated the impact of an additional diagnosis of brain tumor on the cognitive outcome of children with NF1, showing unclear results and without controlling by the effect of surgery, radio-...
Source: Cancers - Category: Cancer & Oncology Authors: Tags: Article Source Type: research
In this study, we explore the ability of SWIG to detect neoplastic tissue and to predict postoperative magnetic resonance imaging (MRI) findings intraoperatively.ProceduresRetrospective data were collected from 36 patients with primary high-grade gliomas (HGG) enrolled as part of a larger trial between October 2014 and October 2018. Patients received systemic ICG infusions at 2.5 –5 mg/kg 24 h preoperatively. Near-infrared fluorescence was recorded throughout the case and from biopsy specimens. The presence/location of residual SWIG signal after resection was compared to the presence/location of residual gadolinium e...
Source: Molecular Imaging and Biology - Category: Molecular Biology Source Type: research
Publication date: March 2020Source: Biomedical Signal Processing and Control, Volume 57Author(s): Navid Ghassemi, Afshin Shoeibi, Modjtaba RouhaniAbstractIn this paper, a new deep learning method for tumor classification in MR images is presented. A deep neural network is first pre-trained as a discriminator in a generative adversarial network (GAN) on different datasets of MR images to extract robust features and to learn the structure of MR images in its convolutional layers. Then the fully connected layers are replaced and the whole deep network is trained as a classifier to distinguish three tumor classes. The deep neu...
Source: Biomedical Signal Processing and Control - Category: Biomedical Science Source Type: research
SummaryThe PI3K/AKT/mTOR pathway activation plays a central role in glioblastoma multiforme (GBM) development and progression, and in resistance to anti-cancer therapies. Inhibition of the PI3K pathway has been shown to sensitize cultured glioma cells and tumor xenografts to the effects of temozolomide (TMZ) and radiation. Vistusertib is an oral inhibitor of mTORC1/2 complexes. The primary objective of this Canadian Cancer Trials Group phase I study was to determine the recommended phase II dose (RP2D) of vistusertib in patients with GBM receiving TMZ at first progression following primary treatment. Vistusertib was admini...
Source: Investigational New Drugs - Category: Drugs & Pharmacology Source Type: research
CONCLUSIONS: Malignant phenotypes of glioma cells were remarkably suppressed through the overexpression of miR-532-5p. MiR-532-5p/CSF1 axis was identified as a new therapeutic intervention for the treatment of glioma. PMID: 31696484 [PubMed - in process]
Source: European Review for Medical and Pharmacological Sciences - Category: Drugs & Pharmacology Tags: Eur Rev Med Pharmacol Sci Source Type: research
More News: Brain Tumor | Glioma | MRI Scan | PET Scan | Physics | Radiation Therapy | Study | X-Ray