Publications by authors named "Landon L"

Introduction: Group living skills (GLS), that is, being tidy and considerate of others, are an important skillset for teams who live and work together. However, this construct does not have a validated measure to enable an understanding of how group living skills influence team dynamics over time. We developed and validated a short measure of group living skills for teams living in extreme work environments.

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Objective: Propose areas of future space human factors research.

Background: Deep space, long-duration human spaceflight missions to the Moon and Mars still require advances in space human factors research. Key drivers relate to astronauts living and working in isolation, new novel technologies required to accomplish exploration missions, and the longer durations of these.

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Background: Numbers of clinical documentation integrity specialists (CDIS) and CDI programs have increased rapidly. CDIS review patient records concurrently with patient admissions and visits to ensure that information is accurate, complete and non-ambiguous, and query clinicians when they see opportunities for improving data. The occupation was initially focused on improving data for reimbursement, but rapid changes to clinical coding requirements, technologies and payment systems led to a quickly evolving role for CDI programs and changes in CDIS practice.

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Identification of asymptomatic patients is necessary to control the COVID-19 pandemic and testing is one of the measures to detect this population. We evaluated the clinical correlation of the DiaSorin Molecular Simplexa COVID-19 Direct (DiaSorin Molecular) and Roche Cobas 6800 SARS-CoV-2 (Roche) assays using 253 oropharyngeal (OP) swab specimens collected from asymptomatic patients. Agreement between DiaSorin Molecular and Roche was 97% (95% CI, 0.

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Long-duration space exploration missions will pose significant risks to the physical and behavioral health and performance of the crew. We documented the presence and frequency of (1) behavioral health and performance (BHP)-relevant symptoms for each condition in NASA's Exploration Medical Conditions List (EMCL), (2) the BHP-relevant effects of applicable medical treatments in the current International Space Station (ISS) On-Orbit Medication List, (3) the breadth of potential BHP impacts of spaceflight medical treatments, and (4) the likelihood of adverse BHP effects of treating spaceflight medical conditions. BHP symptoms and effects were categorized by the six neurobehavioral domains of the National Institute of Mental Health's Research Domain Criteria (RDoC) framework.

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Objectives: To evaluate the clinical performance of 3 molecular assays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Methods: We used 184 nasopharyngeal swab specimens to compare Abbott ID NOW COVID-19 (Abbott ID NOW), DiaSorin Molecular Simplexa COVID-19 Direct (DiaSorin Simplexa), and Roche cobas 6800 SARS-CoV-2 (Roche cobas) assays. In a separate analysis, 3 specimens (nasopharyngeal, oropharyngeal, and nasal) were collected from 182 unique patients presenting to the emergency department with suspicion of coronavirus disease 2019 and were tested utilizing Abbott ID NOW.

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Teams in isolated, confined, and extreme (ICE) environments face many risks to behavioral health, social dynamics, and team performance. Complex long-duration ICE operational settings such as spaceflight and military deployments are largely closed systems with tightly coupled components, often operating as autonomous microsocieties within isolated ecosystems. As such, all components of the system are presumed to interact and can positively or negatively influence team dynamics through direct or indirect pathways.

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In 24/7 operations, fatigue from extended work hours and shift work is ubiquitous. Fatigue is a significant threat to performance, productivity, safety, and well-being, and strategies for managing fatigue are an important area of research. At the level of individuals, the effects of fatigue on performance are relatively well understood, and countermeasures are widely available.

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Many important "grand" challenges-such as sending a team of humans on a voyage to Mars-present superordinate goals that require coordinated efforts across "multiteam systems" comprised of multiple uniquely specialized and interdependent component teams. Given their flexibility and resource capacity, multiteam system structures have great potential to perform in dynamic contexts. However, these systems may fail to achieve their superordinate goals if constituent members or teams do not adapt their collaboration processes to meet the needs of the changing environment.

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Despite the recognized need for clinical nurses to engage in the conduct of research, little is known about their research experiences. This article describes the experiences of nurses who delivered the communication intervention in a behavioral oncology clinical trial for parents of adolescents and young adults (AYAs) with cancer. A qualitative thematic analysis was conducted of nurse interveners' (NIs') reflections on their experiences delivering the communication intervention.

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The scientific study of teamwork in the context of spaceflight has uncovered a considerable amount of knowledge over the past 20 years. Although much is known about the underlying factors and processes of teamwork, much is left to be discovered for teams who will be operating in extreme isolation and confinement during a future Mars mission. Special considerations must be made to enhance teamwork and team well-being for multi-year missions during which the small team will live and work together.

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RNA aptamers that bind human immunodeficiency virus 1 (HIV-1) reverse transcriptase (RT) also inhibit viral replication, making them attractive as therapeutic candidates and potential tools for dissecting viral pathogenesis. However, it is not well understood how aptamer-expression context and cellular RNA pathways govern aptamer accumulation and net antiviral bioactivity. Using a previously-described expression cassette in which aptamers were flanked by two "minimal core" hammerhead ribozymes, we observed only weak suppression of pseudotyped HIV.

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Pregnancy-associated glycoproteins (PAGs) are a large grouping of placental proteins that belong to the aspartic peptidase gene family. Although useful to detect pregnancy in ruminant species, the function of these molecules is unclear. Several PAGs expressed by trophoblast binucleate cells can enter the maternal circulation, suggesting that they could have a systemic role in altering maternal physiology.

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New tumor targeting agents are required to advance cancer diagnosis and treatment. Bacteriophage (phage) display technology, a molecular genetic means of combinatorial drug discovery, is an emerging approach to identify and improve peptide molecules as pharmaceuticals. Peptides are thought to have clinically desirable benefits over currently used biomolecules, such as antibodies, because of their rapid blood clearance, increased diffusion and tissue penetration, non-immunogenic nature and ease of synthesis.

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Intravascular cancer cell adhesion plays a significant role in the metastatic process. Studies indicate that galectin-3, a member of the galectin family of soluble animal lectins, is involved in carbohydrate-mediated metastatic cell heterotypic (between carcinoma cells and endothelium) and homotypic (between carcinoma cells) adhesion via interactions with the tumor-specific Thomsen-Friedenreich glycoantigen (TFAg). We hypothesized that blocking the galectin-3 carbohydrate recognition domain with synthetic peptides would significantly reduce metastasis-associated carcinoma cell adhesion.

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In vivo phage display is a new approach to acquire peptide molecules that bind stably to a given target. Phage peptide display libraries have been selected in mice and humans and numerous vasculature-targeting peptides have been reported. However, in vivo phage display has not typically produced molecules that extravasate to target specific organ or tumor antigens.

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Fluorescence spectroscopy titrations, although widely used to analyze binding affinity, are not an efficient screening method for detecting high-affinity binding among a large number of available ligands, such as during bacteriophage display selections. We hypothesize that a miniaturized, high-throughput fluorescence spectroscopy assay can be used to efficiently analyze selection results by applying the Langmuir equation to the binding data to estimate affinity constants for a large number of ligands, either as synthesized molecules or as displayed on bacteriophage. Here, bacteriophage-display-derived peptides specific for the Thomsen-Friedenreich disaccharide are used to develop a high-throughput fluorescence spectroscopy screening method, which uses one binding partner labeled with a fluorescent dye and different concentrations of a second partner to analyze binding affinity in bacteriophage display selections.

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The Thomsen-Friedenreich antigen, a carcinoma-associated disaccharide involved in carcinoma cell homotypic aggregation and increased metastatic potential, has clinical value as a prognostic indicator and a marker of metastasized cells. Hence, it can reasonably be predicted that antigen-binding macromolecules are valuable clinical in vivo diagnostic/therapeutic targeting agents. Recently, we have selected first-generation antigen-binding peptides from a random peptide bacteriophage display library and have applied combinatorial affinity maturation to select functionally-maturated peptides, which target cultured carcinoma cells and inhibit carcinoma cell aggregation.

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The B-cell lymphoma/leukemia-2 (bcl-2) proto-oncogene has been associated with the transformation of benign lesions to malignancy, disease progression, poor prognosis, reduced survival, and development of resistance to radiation and chemotherapy in many types of cancer. The objective of this work was to synthesize an antisense peptide nucleic acid (PNA) complementary to the first six codons of the bcl-2 open reading frame, conjugated to a membrane-permeating peptide for intracellular delivery, and modified with a bifunctional chelating agent for targeting imaging and therapeutic radiometals to tumors overexpressing bcl-2. Four peptide-PNA constructs were synthesized by a combination of manual and automated stepwise elongation techniques, including bcl-2 antisense conjugates and nonsense conjugates with no complementarity to any known mammalian gene or DNA sequence.

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Peptides possess appropriate pharmacokinetic properties to serve as cancer imaging or therapeutic targeting agents. Currently, only a small number of rationally-derived, labeled peptide analogues that target only a limited subset of antigens are available. Thus, finding new cancer targeting peptides is a central goal in the field of molecular targeting.

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Thomsen-Friedenreich (TF) antigen occurs on approximately 90% of human carcinomas, is likely involved in carcinoma cell homotypic aggregation, and has clinical value as a prognostic indicator and marker of metastasized cells. Previously, we isolated anti-TF antigen peptides from bacteriophage display libraries. These bound to TF antigen on carcinoma cells but were of low affinity and solubility.

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1. Serotonin (5-hydroxytryptamine, 5-HT) has been shown to increase cyclic AMP production in dispersed cell aggregates from the major salivary glands of the rat. The goal of the present study was to identify the 5-HT receptor subtypes that mediate these effects in rat submandibular glands (SMG).

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The effects of ATP on salivary glands have been recognized since 1982. Functional and pharmacological studies of the P2 nucleotide receptors that mediate the effects of ATP and other extracellular nucleotides have been supported by the cloning of receptor cDNAs, by the expression of the receptor proteins, and by the identification in salivary gland cells of multiple P2 receptor subtypes. Currently, there is evidence obtained from pharmacological and molecular biology approaches for the expression in salivary gland of two P2X ligand-gated ion channels, P2Z/P2X7 and P2X4, and two P2Y G protein-coupled receptors, P2Y1 and P2Y2.

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