Medicine and Health Sciences Commons^™

Radiotherapy-Compatible Robotic System For Multi-Landmark Positioning In Head And Neck Cancer Treatments, Mark Ostyn, Siqiu Wang, Yun-Soung Kim, Siyong Kim, Woon-Hong Yeo

Radiation Oncology Publications

The spine flexibility creates one of the most significant challenges to proper positioning in radiation therapy of head and neck cancers. Even though existing immobilization techniques can reduce the positioning uncertainty, residual errors (2–3 mm along the cervical spine) cannot be mitigated by single translation-based approaches. Here, we introduce a fully radiotherapy-compatible electro-mechanical robotic system, capable of positioning a patient’s head with submillimeter accuracy in clinically acceptable spatial constraints. Key mechanical components, designed by finite element analysis, are fabricated with 3D printing and a cyclic loading test of the printed materials captures a great mechanical robustness. Measured attenuation of most …

Feasibility Of Integrating Tripterygium Wilfordii Into Modern Cancer Therapy For Increased Efficacy With Minimal Toxicity, Andy Vo

Auctus: The Journal of Undergraduate Research and Creative Scholarship

Cancer is the second leading cause of death in the U.S., and millions of novel cancer cases are being diagnosed each year. While chemotherapy and ionizing radiation are effective treatments against these malignant tumors, the adverse effects that accompany such treatments are devastating. In order to find alternative treatment methods with less side effects, we turn to Eastern herbal medicine. Recent scientific research has found that Tripterygium wilfordii, an herbal medicine traditionally used to treat inflammation in China, contains compounds (triptolide and celastrol) that prevent the growth of solid tumors, induce apoptosis, and prevent metastasis of developed tumors. Investigations on …

Evaluation Of The Performance Of Smoothing Functions In Generalized Additive Models For Spatial Variation In Disease, Umaporn Siangphoe, David C. Wheeler

Biostatistics Publications

Generalized additive models (GAMs) with bivariate smoothing functions have been applied to estimate spatial variation in risk for many types of cancers. Only a handful of studies have evaluated the performance of smoothing functions applied in GAMs with regard to different geographical areas of elevated risk and different risk levels. This study evaluates the ability of different smoothing functions to detect overall spatial variation of risk and elevated risk in diverse geographical areas at various risk levels using a simulation study. We created five scenarios with different true risk area shapes (circle, triangle, linear) in a square study region. We …

Penalized Ordinal Regression Methods For Predicting Stage Of Cancer In High-Dimensional Covariate Spaces, Amanda Elswick Gentry, Colleen K. Jackson-Cook, Debra E. Lyon, Kellie J. Archer

Biostatistics Publications

The pathological description of the stage of a tumor is an important clinical designation and is considered, like many other forms of biomedical data, an ordinal outcome. Currently, statistical methods for predicting an ordinal outcome using clinical, demographic, and high-dimensional correlated features are lacking. In this paper, we propose a method that fits an ordinal response model to predict an ordinal outcome for high-dimensional covariate spaces. Our method penalizes some covariates (high-throughput genomic features) without penalizing others (such as demographic and/or clinical covariates). We demonstrate the application of our method to predict the stage of breast cancer. In our model, …

Catchment Area Analysis Using Bayesian Regression Modeling, Aobo Wang, David C. Wheeler

Biostatistics Publications

A catchment area (CA) is the geographic area and population from which a cancer center draws patients. Defining a CA allows a cancer center to describe its primary patient population and assess how well it meets the needs of cancer patients within the CA. A CA definition is required for cancer centers applying for National Cancer Institute (NCI)-designated cancer center status. In this research, we constructed both diagnosis and diagnosis/treatment CAs for the Massey Cancer Center (MCC) at Virginia Commonwealth University. We constructed diagnosis CAs for all cancers based on Virginia state cancer registry data and Bayesian hierarchical logistic regression …

Diabetes Management Before And After Cancer Diagnosis: Missed Opportunity, Nengliang Yao, Fabian T. Camacho, Askar S. Chukmaitov, Steven T. Fleming, Roger T. Anderson

Health Behavior and Policy Publications

Background

Few studies have examined the management of comorbidities in cancer patients. This study used population-based data to estimate the guideline concordance rates for diabetes management before and after cancer diagnosis and examined if diabetes management services among cancer patients was associated with characteristics of the hospital where the patient was treated.

Methods

We linked 2005-2009 Medicare claims data to information on 2,707 breast and colorectal cancers patients in state cancer registry files. Multivariate logistic regression models examined hospital characteristics associated with receipt of diabetes management care after cancer diagnosis.

Results

The rates of HbAlc testing, LDL-C testing, and retinal …

Impaired Clearance Of Methotrexate In Organic Anion Transporter 3 (Slc22a8) Knockout Mice: A Gender Specific Impact Of Reduced Folates, Adam L. Vanwert, Douglas H. Sweet

Pharmaceutics Publications

Purpose

To elucidate the role of the renal basolateral transporter, Oat3, in the disposition of methotrexate.

Materials and Methods

Chinese hamster ovary cells expressing mouse Oat3 were used to determine kinetics and specificity of inhibition of methotrexate transport. Methotrexate clearance was then examined in vivo in wildtype and Oat3 knockout mice.

Results

NSAIDs, ß-lactams, and uremic toxins inhibited mOat3-mediated methotrexate uptake by 70–100%, while folate, leucovorin, and 5-methyltetrahydrofolate inhibited transport by 25–50%. A Km of 60.6±9.3 μM for methotrexate transport was determined. Oat3 knockout mice exhibited reduced methotrexate-to-inulin clearance ratios versus wildtype. Male wildtype mice, but not knockouts or …