Andrew Jackson

Bio: Andrew Jackson is an academic researcher from Memorial Sloan Kettering Cancer Center. The author has contributed to research in topics: Small-angle neutron scattering & Neutron scattering. The author has an hindex of 55, co-authored 195 publications receiving 13852 citations. Previous affiliations of Andrew Jackson include Lund University & National Institute of Standards and Technology.

Use of normal tissue complication probability models in the clinic.

Abstract: The Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) review summarizes the currently available three-dimensional dose/volume/outcome data to update and refine the normal tissue dose/volume tolerance guidelines provided by the classic Emami et al. paper published in 1991. A "clinician's view" on using the QUANTEC information in a responsible manner is presented along with a description of the most commonly used normal tissue complication probability (NTCP) models. A summary of organ-specific dose/volume/outcome data, based on the QUANTEC reviews, is included.

Quantitative Analyses of Normal Tissue Effects in the Clinic (QUANTEC): An Introduction to the Scientific Issues

Abstract: Advances in dose-volume/outcome (or normal tissue complication probability, NTCP) modeling since the seminal Emami paper from 1991 are reviewed. There has been some progress with an increasing number of studies on large patient samples with three-dimensional dosimetry. Nevertheless, NTCP models are not ideal. Issues related to the grading of side effects, selection of appropriate statistical methods, testing of internal and external model validity, and quantification of predictive power and statistical uncertainty, all limit the usefulness of much of the published literature. Synthesis (meta-analysis) of data from multiple studies is often impossible because of suboptimal primary analysis, insufficient reporting and variations in the models and predictors analyzed. Clinical limitations to the current knowledge base include the need for more data on the effect of patient-related cofactors, interactions between dose distribution and cytotoxic or molecular targeted agents, and the effect of dose fractions and overall treatment time in relation to nonuniform dose distributions. Research priorities for the next 5-10 years are proposed.

Radiation dose-volume effects in the lung.

Abstract: The three-dimensional dose, volume, and outcome data for lung are reviewed in detail. The rate of symptomatic pneumonitis is related to many dosimetric parameters, and there are no evident threshold "tolerance dose-volume" levels. There are strong volume and fractionation effects.

Incidence of Late Rectal and Urinary Toxicities After Three-Dimensional Conformal Radiotherapy and Intensity-Modulated Radiotherapy for Localized Prostate Cancer

Abstract: Purpose To report the incidence and predictors of treatment-related toxicity at 10 years after three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) for localized prostate cancer. Methods and Materials Between 1988 and 2000, 1571 patients with stages T1–T3 prostate cancer were treated with 3D-CRT/IMRT with doses ranging from 66 to 81 Gy. The median follow-up was 10 years. Posttreatment toxicities were all graded according to the National Cancer Institute's Common Terminology Criteria for Adverse Events. Results The actuarial likelihood at 10 years for the development of Grade ≥2 GI toxicities was 9%. The use of IMRT significantly reduced the risk of gastrointestinal (GI) toxicities compared with patients treated with conventional 3D-CRT (13% to 5%; p p p = 0.01). Among patients who had developed acute symptoms during treatment, the incidence of late toxicity at 10 years was 35%, compared with 12% ( p Conclusions Serious late toxicity was unusual despite the delivery of high radiation dose levels in these patients. Higher doses were associated with increased GI and GU Grade 2 toxicities, but the risk of proctitis was significantly reduced with IMRT. Acute symptoms were a precursor of late toxicities in these patients.

Radiation Dose–Volume Effects in Radiation-Induced Rectal Injury

Abstract: The available dose/volume/outcome data for rectal injury were reviewed. The volume of rectum receiving ≥60Gy is consistently associated with the risk of Grade ≥2 rectal toxicity or rectal bleeding. Parameters for the Lyman-Kutcher-Burman normal tissue complication probability model from four clinical series are remarkably consistent, suggesting that high doses are predominant in determining the risk of toxicity. The best overall estimates (95% confidence interval) of the Lyman-Kutcher-Burman model parameters are n = 0.09 (0.04–0.14); m = 0.13 (0.10–0.17); and TD50 = 76.9 (73.7–80.1) Gy. Most of the models of late radiation toxicity come from three-dimensional conformal radiotherapy dose-escalation studies of early-stage prostate cancer. It is possible that intensity-modulated radiotherapy or proton beam dose distributions require modification of these models because of the inherent differences in low and intermediate dose distributions.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Update of the CHARMM All-Atom Additive Force Field for Lipids: Validation on Six Lipid Types

Abstract: A significant modification to the additive all-atom CHARMM lipid force field (FF) is developed and applied to phospholipid bilayers with both choline and ethanolamine containing head groups and with both saturated and unsaturated aliphatic chains. Motivated by the current CHARMM lipid FF (C27 and C27r) systematically yielding values of the surface area per lipid that are smaller than experimental estimates and gel-like structures of bilayers well above the gel transition temperature, selected torsional, Lennard-Jones and partial atomic charge parameters were modified by targeting both quantum mechanical (QM) and experimental data. QM calculations ranging from high-level ab initio calculations on small molecules to semiempirical QM studies on a 1,2-dipalmitoyl-sn-phosphatidylcholine (DPPC) bilayer in combination with experimental thermodynamic data were used as target data for parameter optimization. These changes were tested with simulations of pure bilayers at high hydration of the following six lipids: ...

Radiomics: the bridge between medical imaging and personalized medicine

Abstract: Radiomics, the high-throughput mining of quantitative image features from standard-of-care medical imaging that enables data to be extracted and applied within clinical-decision support systems to improve diagnostic, prognostic, and predictive accuracy, is gaining importance in cancer research. Radiomic analysis exploits sophisticated image analysis tools and the rapid development and validation of medical imaging data that uses image-based signatures for precision diagnosis and treatment, providing a powerful tool in modern medicine. Herein, we describe the process of radiomics, its pitfalls, challenges, opportunities, and its capacity to improve clinical decision making, emphasizing the utility for patients with cancer. Currently, the field of radiomics lacks standardized evaluation of both the scientific integrity and the clinical relevance of the numerous published radiomics investigations resulting from the rapid growth of this area. Rigorous evaluation criteria and reporting guidelines need to be established in order for radiomics to mature as a discipline. Herein, we provide guidance for investigations to meet this urgent need in the field of radiomics.