Publications by authors named "Christopher Dell"

Lymph nodes and other secondary lymphoid organs play critical roles in immune surveillance and immune activation in mammals, but the deep internal locations of these organs make it challenging to image and study them in living animals. Here, we describe a previously uncharacterized external immune organ in the zebrafish ideally suited for studying immune cell dynamics , the axillary lymphoid organ (ALO). This small, translucent organ has an outer cortex teeming with immune cells, an inner medulla with a mesh-like network of fibroblastic reticular cells along which immune cells migrate, and a network of lymphatic vessels draining to a large adjacent lymph sac.

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Background: The United States Food and Drug Administration is developing a series of patient-focused drug development guidance documents regarding the collection of patient experience data, including methods for understanding treatment benefit from the patient perspective. The goal of this research was to investigate the concern that the global impression of change scale is subject to recall error and thus not optimal for use as an anchor for estimating meaningful within-person change thresholds. We explored whether memory assistance for recalling baseline status would make a difference in how study participants diagnosed with Parkinson's disease (PD) responded to a patient global impression of change (PGIC) and patient global impression static (PGIS) item.

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Background: Scrolling is a perceived barrier in the use of bring your own device (BYOD) to capture electronic patient reported outcomes (ePROs). This study explored the impact of scrolling on the measurement equivalence of electronic patient-reported outcome measures (ePROMs) in the presence and absence of scrolling.

Methods: Adult participants with a chronic condition involving daily pain completed ePROMs on four devices with different scrolling properties: a large provisioned device not requiring scrolling; two provisioned devices requiring scrolling - one with a "smart-scrolling" feature that disabled the "next" button until all information was viewed, and a second without this feature; and BYOD with smart-scrolling.

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Mobile technologies offer the potential to reduce the costs of conducting clinical trials by collecting high-quality information on health outcomes in real-world settings that are relevant to patients and clinicians. However, widespread use of mobile technologies in clinical trials has been impeded by their perceived challenges. To advance solutions to these challenges, the Clinical Trials Transformation Initiative (CTTI) has issued best practices and realistic approaches that clinical trial sponsors can now use.

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Background: This paper is a comment on the idea of matrix-free Cladistics. Demonstration of this idea's efficiency is a major goal of the study. Within the proposed framework, the ordinary (phenetic) matrix is necessary only as "source" of Hennigian trees, not as a primary subject of the analysis.

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Outcomes research literature has many examples of high-quality, reliable patient-reported outcome (PRO) data entered directly by electronic means, ePRO, compared to data entered from original results on paper. Clinical trial managers are increasingly using ePRO data collection for PRO-based end points. Regulatory review dictates the rules to follow with ePRO data collection for medical label claims.

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The development of biological informatics infrastructure capable of supporting growing data management and analysis environments is an increasing need within the systematics biology community. Although significant progress has been made in recent years on developing new algorithms and tools for analyzing and visualizing large phylogenetic data and trees, implementation of these resources is often carried out by bioinformatics experts, using one-off scripts. Therefore, a gap exists in providing data management support for a large set of non-technical users.

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