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Purpose: A hybrid principal component analysis and projection onto dipole fields (PCA-PDF) MR thermometry motion compensation algorithm was optimized with atlas image augmentation and validated. Methods: Experiments were conducted on a 3T Philips MRI and Profound V1 Sonalleve high intensity focused ultrasound (high intensity focused ultrasound system. An MR-compatible robot was configured to induce motion on custom gelatin phantoms. Trials with periodic and sporadic motion were introduced on phantoms while hyperthermia was administered. The PCA-PDF algorithm was augmented with a predictive atlas to better compensate for larger sporadic motion. Results: During periodic motion, the temperature SD in the thermometry was improved from 1.1 ± 0.1 to 0.5 ± 0.1°C with both the original and augmented PCA-PDF application. For large sporadic motion, the augmented atlas improved the motion compensation from the original PCA-PDF correction from 8.8 ± 0.5 to 0.7 ± 0.1°C. Conclusion: The PCA-PDF algorithm improved temperature accuracy to <1°C during periodic motion, butwas not able to adequately address sporadicmotion. By augmenting the PCA-PDF algorithm, temperature SD during large sporadic motion was also reduced to <1°C, greatly improving the original PCA-PDF algorithm. [ABSTRACT FROM AUTHOR]

The expansion of pluripotent stem cells (PSCs) in vitro remains a critical barrier to their use in tissue engineering and regenerative medicine. Biochemical methods for PSC expansion are known to produce heterogeneous cell populations with varying states of pluripotency and are cost-intensive, hindering their clinical translation. Engineering biomaterials to physically control PSC fate offers an alternative approach. Surface or substrate topography is a promising design parameter for engineering biomaterials. Topographical cues have been shown to elicit profound effects on stem cell differentiation and proliferation. Previous reports have shown isotropic substrate topographies to be promising in expanding PSCs. However, the optimal feature to promote PSC proliferation and the pluripotent state has not yet been determined. In this work, the MultiARChitecture (MARC) plate is developed to conduct a high-throughput analysis of topographical cues in a 96-well plate format. The MARC plate is a reproducible and customizable platform for the analysis of multiple topographical patterns and features and is compatible with both microscopic assays and molecular biology techniques. The MARC plate is used to evaluate the expression of pluripotency markers Oct4, Nanog , and Sox2 and the differentiation marker LmnA as well as the proliferation of murine embryonic stem (mES) cells. Our systematic analyses identified three topographical patterns that maintain pluripotency in mES cells after multiple passages: 1 µ m pillars (1 µ m spacing, square arrangement), 2 µ m wells (c-c ( x, y ) = 4, 4 µ m), and 5 µ m pillars (c-c ( x, y ) = 7.5, 7.5 µ m). This study represents a step towards developing a biomaterial platform for controlled murine PSC expansion., (Creative Commons Attribution license.)

Purpose: Lack of knowledge and negative attitudes have been identified as barriers to participation in clinical trials by patients with cancer. We developed Preparatory Education About Clinical Trials (PRE-ACT), a theory-guided, Web-based, interactive computer program, to deliver tailored video educational content to patients in an effort to overcome barriers to considering clinical trials as a treatment option., Patients and Methods: A prospective, randomized clinical trial compared PRE-ACT with a control condition that provided general clinical trials information produced by the National Cancer Institute (NCI) in text format. One thousand two hundred fifty-five patients with cancer were randomly allocated before their initial visit with an oncologist to PRE-ACT (n = 623) or control (n = 632). PRE-ACT had three main components: assessment of clinical trials knowledge and attitudinal barriers, values assessment with clarification back to patients, and provision of a video library tailored to address each patient's barriers. Outcomes included knowledge and attitudes and preparation for decision making about clinical trials., Results: Both PRE-ACT and control interventions improved knowledge and attitudes (all P < .001) compared with baseline. Patients randomly allocated to PRE-ACT showed a significantly greater increase in knowledge (P < .001) and a significantly greater decrease in attitudinal barriers (P < .001) than did their control (text-only) counterparts. Participants in both arms significantly increased their preparedness to consider clinical trials (P < .001), and there was a trend favoring the PRE-ACT group (P < .09). PRE-ACT was also associated with greater patient satisfaction than was NCI text alone., Conclusion: These data show that patient education before the first oncologist visit improves knowledge, attitudes, and preparation for decision making about clinical trials. Both text and tailored video were effective. The PRE-ACT interactive video program was more effective than NCI text in improving knowledge and reducing attitudinal barriers., Competing Interests: Authors' disclosures of potential conflicts of interest are found in the article online at www.jco.org. Author contributions are found at the end of this article., (© 2015 by American Society of Clinical Oncology.)