Cancer-related ectopic expression of the bone-related transcription factor RUNX2 in non-osseous metastatic tumor cells is linked to cell proliferation and motility

10.1186/bcr2762Breast Cancer Research125-BCRR

Extraction and transport of ion beams from an ECR ion source

Ion beams extracted from an Electron Cyclotron Resonance (ECR) ion sources have, compared to other types of ion sources, a relatively large and correlated emittance and therefore transport of these beams is a challenging task. In this thesis an extensive simulation study based on ion trajectory calculations of the beam formation, extraction and transport of highly charged ions from an ECR source is presented. This study concentrates on the full three dimensional (3D) simulation of beam extraction and transport. Both higher order aberrations and space-charge effects have been investigated by analyzing the 4D phase-space distributions of the ions at various positions along the beamline. The simulations and measurements show good agreement which indicates that the important physical processes are properly incorporated in the codes. The simulations demonstrate that non-paraxiality is a very important aspect for low energy ion beams extracted from ECR sources and that the fringe fields of the magnets cause significant second-order aberrations leading to a strong increase of the effective emittance. Furthermore it has been demonstrated that by suitably modifying the pole faces of the magnets the effective emittance growth can be significantly reduced. The simulations also clearly show that full space-charge compensation of the extracted ion beam is important to minimize the emittance degradation. To ensure satisfactory transmission of the high intensity beams from the new generation of superconducting ECR ion sources beam optics and space-charge compensation will definitely require more attention than they have got up to now.

Dosimetric comparison of normal breathing and deep inspiration breath hold technique for synchronous bilateral breast cancer using 6MV flattened beam and flattening filter free beam

Background: The present study was to investigate the usefulness of deep inspiration breath hold (DIBH) in bilateral breast patients using 6MV flattened beam (FB) and flattening filter free beam (FFFB). Materials and methods: Twenty bilateral breast cancer patients were simulated, using left breast patients treated with DIBH technique. CT scans were performed in the normal breathing (NB) and DIBH method. Three-dimensional conformal radiotherapy (3DCRT) and volumetric arc therapy (VMAT) plans were generated. Results: In our study the best organ at risk (OAR) sparing is achieved in the 3DCRT DIBH plan with adequate PTV coverage (V95 ≥ 47.5 Gy) as compared to 6MV FB and FFFB VMAT DIBH plans. The DIBH scan plan reduces the heart mean dose significantly at the rate of 49% in 3DCRT (p = 0.00) and 22% in VMAT (p = 0.010). Similarly, the DIBH scan plan produces lesser common lung mean dose of 18% in 3DCRT (p = 0.011) and 8% in VMAT (0.007) as compared to the NB scan. The conformity index is much better in VMAT FB (1.04 ± 0.04 vs. 1.04 ± 0.05), p =1.00 and VMAT FFFB (1.04 ± 0.05 vs. 1 ± 0.24, p = 0.345) plans as compared to 3DCRT (1.63 ± 0.2 vs. 1.47 ± 0.28, p = 0.002). The homogeneity index of all the plans is less than 0.15. The global dmax is more in VMAT FFFB DIBH plan (113.7%). The maximum MU noted in the NB scan plan (478 vs. 477MU, 1366 vs. 1299 MU and 1853 vs. 1788 MU for 3DCRT, VMAT FB and VMAT FFFB technique as compared to DIBH scan. Conclusion: We recommend that the use of DIBH techniques for bilateral breast cancer patients significantly reduces the radiation doses to OARs in both 3DCRT and VMAT plans.

Small forms of Blastocystis hominis

Unusually small forms of Blastocystis hominis were found in the stools of Indonesian immigrants. The size of the parasites seen in faecal samples of the Indonesian isolates were 3 ' 5 mm whereas larger vacuolar forms measuring 10 ' 15 mm were seen Malaysian and Bangladeshi isolates. These small forms showed a distinct growth profile with an optimum parasite yield as high as 11.7 ' 105 when cultured in Jone's medium compared to yield of 3.9 ' 105 and 0.5 ' 105 for Malaysian and Bangladeshi isolates respectively. The unusually small forms of Blastocystis, unlike the other isolates, was found to grow in cultures at 37'C even after being kept at room temperature for as long as 9 days