• Timmons Mack posted an update 6 months, 4 weeks ago

    EMT modulation could constitute an approach to avoid metastasis. Some of the targeted small molecules utilized as antiproliferative agents have revealed to inhibit EMT initiation or maintenance because EMT is regulated through signaling pathways for which these molecules have been designed. INTRODUCTION Volumetric biomarkers for Alzheimer disease (AD) are attractive due to their wide availability and ease of administration, but have traditionally shown lower diagnostic accuracy than measures of neuropathological contributors to AD. Our purpose was to optimize the diagnostic specificity of structural MRIs for AD using quantitative, data-driven techniques. METHODS This retrospective study assembled several non-overlapping cohorts (total n = 1287) with publicly available data and clinical patients from Barnes-Jewish Hospital (data gathered 1990-2018). The Normal Aging Cohort (n = 383) contained amyloid biomarker negative, cognitively normal (CN) participants, and provided a basis for determining age-related atrophy in other cohorts. The Training (n = 216) and Test (n = 109) Cohorts contained participants with symptomatic AD and CN controls. Classification models were developed in the Training Cohort and compared in the Test Cohort using the receiver operating characteristics areas under curve (AUCsividuals with symptomatic AD from CN controls and other dementia types but were not improved by controlling for normal aging. PURPOSE Monte Carlo (MC) simulations are highly desirable for dose treatment planning and evaluation in radiation oncology. This is true also in emerging nuclear medicine applications such as internal radiotherapy with radionuclides. The purpose of this study is the validation of irtGPUMCD, a GPU-based MC code for dose calculations in internal radiotherapy. METHODS The female and male phantoms of the International Commission on Radiological Protection (ICRP 110) were used as benchmarking geometries for this study focused on 177Lu and including 99mTc and 131I. Dose calculations were also conducted for a real patient. For phantoms, twelve anatomical structures were considered as target/source organs. The S-values were evaluated with irtGPUMCD simulations (108 photons), with gamma branching ratios of ICRP 107 publication. The 177Lu electrons S-values were calculated for source organs only, based on local deposition of dose in irtGPUMCD. The S-value relative difference between irtGPUMCD and IDAC-DOSE were evaluated for all targets/sources considered. A DVHs comparison with GATE was conducted. An exponential track length estimator was introduced in irtGPUMCD to increase computational efficiency. RESULTS The relative S-value differences between irtGPUMCD and IDAC-DOSE were less then 5% while this comparison with GATE was less then 1%. The DVHs dosimetric indices comparison between GATE and irtGPUMCD for the patient led to an excellent agreement ( less then 2%). The time required for the simulation of 108 photons was 1.5 min for the female phantom, and one minute for the real patient ( less then 1% uncertainty). These results are promising and let envision the use of irtGPUMCD for internal dosimetry in clinical applications. PURPOSE The aim of this study was to establish complexity-based local diagnostic reference levels (DRLs) for standard endovascular aneurysm repair (EVAR) procedures. METHODS Dosimetric data for 73 consecutive patients were collected prospectively. All procedures were performed on a Siemens Axiom Artis FA angiographic unit (Siemens, Erlangen, Germany). Fluoroscopy time (FT), dose area product (DAP), air kerma (Ka.r) at reference point as well as patient’s age, height and weight were recorded for each procedure. Moreover, the complexity level of each procedure was evaluated. Spearman rank correlation tests were used to evaluate the degree of association between variables. RESULTS 2nd quartiles of DAP for low, medium and high complexity standard EVAR procedures were 144.2 Gycm2, 160.1 Gycm2 and 189.5 Gycm2respectively. The median DAP of the full sample was 153.2 Gycm2. Statistical analysis showed a strong correlation between BMI and DAP (r = 0.68, p-value  less then  0.0001) and a moderate correlation between BMI and Ka.r (r = 0.52, p-value  less then  0.0001). Furthermore, a strong correlation was found between Ka.r and FT (r = 0.76, p-value  less then  0.0001) and a moderate correlation was found between DAP and FT (r = 0.57, p-value  less then  0.0001). CONCLUSION The complexity of an EVAR procedure is associated with the total burden of radiation. Establishment of complexity-based DRLs for interventional radiology procedures can contribute to the radiation protection of patients and staff. SBC-115076 chemical structure Introduction Some patients with locally advanced cervical cancer (LACC) cannot undergo brachytherapy (BT). Possible treatment includes two-stage external beam radiotherapy (sequential boost – SEQ) or single-stage external beam radiotherapy (simultaneous integrated boost – SIB). The goal of this paper was to carry out dosimetric and radiobiological comparison of these techniques with respect to tumour and organs-at-risk (OARs) irradiation. Methods The anatomic data of six patients with LACC were used for this study. The single-stage SIB-VMAT (25, 27 or 30 fractions) and double-stage SEQ-VMAT (25 + 6 fractions) plans were developed to deliver EQD2=50 Gy to the pelvic region and EQD2=90 Gy to the tumour. The developed plans were compared with respect to an EQD2 dose delivered to a tumour and to the OARs, expected tumour control probability and normal tissue complications probability. Results The developed SIB-VMAT and SEQ-VMAT plans had physical coverage of the CTV tumours with more than 95% of the prescribed dose delivered to more than 95% of the volume. The irradiation of the tumour for both SIB-VMAT and SEQ-VMAT has comparable EQD2 values close to 87-88 Gy. SIB-VMAT treatment plans provided lower levels of irradiation of OARs than SEQ-VMAT plans. The optimal number of fractions for SIB-VMAT was 27. Conclusion SIB-VMAT is a better treatment option for patients with LACC that are not eligible for BT. Results show that both SIB-VMAT and SEQ-VMAT allowed good coverage of the tumour and high-quality dose delivery. SIB-VMAT allowed minimising irradiation of OARs and shortening the overall treatment time by a week.

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