Publications by authors named "Dale Johnson"

Objective: The doctor of chiropractic program (DCP) graduate must demonstrate competency in clinical research literacy (CRL), per accreditation standards. This study aimed to compare student CRL knowledge, confidence, and attitudes between the beginning and end of their DCP.

Methods: We collected data on 245 matriculating students' CRL knowledge, confidence, and attitudes between 2017 and 2018.

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Due to the severity and frequency of cervical spine injuries, the neck injury criterion (Nij) was developed to provide a quantitative relationship between forces and moments of the upper neck with accompanied injury risk. The present study was undertaken to evaluate differences in calculated Nij for the Global Human Body Model Consortium's detailed and simplified average 50th percentile male models. The simplified model is a computationally light version of the more detailed model and therefore it is of interest to achieve similar Nij values between the two models.

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The goal of this study was to implement active musculature into the Global Human Body Models Consortium (GHBMC) average male simplified occupant model (M50-OS v2) and validate its performance in low-speed frontal crash scenarios. Volunteer and postmortem human subjects (PMHS) data from low-speed frontal sled tests by Beeman et al., including 2.

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Background: Duodenal diverticula tend to be asymptomatic; however, patients may develop duodenal diverticulitis.

Case Presentation: A 66-year-old Caucasian man presented to our emergency room with a two-day history of right-sided abdominal pain, chills, tachycardia, nausea, and emesis. His WBC, lactic acid, and bilirubin were elevated.

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Background: Lumbar hernias are rare abdominal hernias. Surgery is the only treatment option but remains challenging. Posterior incisional hernias are even rarer especially with incarceration of intra-abdominal contents.

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An investigation into the perceptual threshold of apparent source width (ASW) in relation to a single reflection azimuth was performed in binaural reproduction. In the presence of a direct sound, subjects compared the ASW produced by a single 90° reference reflection against ASW produced by a test reflection with a varying angle for four reflection delay times between 5 and 30 ms. Threshold angles were found to be approximately 40° and 130°, and did not appear to be dependent on delay time.

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Biotherapeutics are a rapidly growing portion of the total pharmaceutical market accounting for almost one-half of recent new drug approvals. A major portion of these approvals each year are monoclonal antibodies (mAbs). During development, non-clinical pharmacology and toxicology testing of mAbs differs from that done with chemical entities since these biotherapeutics are derived from a biological source and therefore the animal models must share the same epitopes (targets) as humans to elicit a pharmacological response.

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As the duration of manned missions outside of the Earth's protective shielding increase, astronauts are at risk for exposure to space radiation. Various organ systems may be damaged due to exposure. This study investigates the bone strength changes using finite element modeling of Long Evans rats (n=85) subjected to graded, head-only proton (0, 10, 25, and 100 cGy, 150 MeV/n) and silicon (0, 10, 25, and 50 cGy, 300 MeV/n) radiation.

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Arginase deficiency is caused by deficiency of arginase 1 (ARG1), a urea cycle enzyme that converts arginine to ornithine. Clinical features of arginase deficiency include elevated plasma arginine levels, spastic diplegia, intellectual disability, seizures and growth deficiency. Unlike other urea cycle disorders, recurrent hyperammonemia is typically less severe in this disorder.

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Background: Current approaches to chemical screening, prioritization, and assessment are being reenvisioned, driven by innovations in chemical safety testing, new chemical regulations, and demand for information on human and environmental impacts of chemicals. To conceptualize these changes through the lens of a prevalent disease, the Breast Cancer and Chemicals Policy project convened an interdisciplinary expert panel to investigate methods for identifying chemicals that may increase breast cancer risk.

Methods: Based on a review of current evidence, the panel identified key biological processes whose perturbation may alter breast cancer risk.

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Valproic acid is approved for treatment of seizures and manic episodes of bipolar disorder, and continues to be one of the most commonly prescribed antiepileptic drugs in the world. Hepatotoxicity is a rare but serious side effect resulting from its use, particularly in young patients. This adverse effect does not display normal dose-response curves and can be lethal in children.

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Background: One hundred and sixty million office workers (knowledge workers) in the U.S. and 2/3 of the developed countries use computers on a daily basis.

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Objective: This report describes the case management of musculoskeletal disorders for an employee in a college work environment using both chiropractic care and applied ergonomics.

Clinical Findings: A 54-year-old male office worker presented with decreased motor function in both wrists; intermittent moderate-to-severe headaches; and pain or discomfort in the neck, both shoulders, left hand and wrist, and lumbosacral region resulting from injuries sustained during recreational soccer and from excessive forces and awkward postures when interacting with his home and office computer workstations.

Intervention And Results: Ergonomic training, surveillance, retrofitted equipment with new furniture, and an emphasis on adopting healthy work-style behaviors were applied in combination with regular chiropractic care.

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Disturbance affects most terrestrial ecosystems and has the potential to shape their responses to chronic environmental change. Scrub-oak vegetation regenerating from fire disturbance in subtropical Florida was exposed to experimentally elevated carbon dioxide (CO₂) concentration (+350 μl l(-1)) using open-top chambers for 11 yr, punctuated by hurricane disturbance in year 8. Here, we report the effects of elevated CO₂ on aboveground and belowground net primary productivity (NPP) and nitrogen (N) cycling during this experiment.

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Rising atmospheric carbon dioxide (CO₂) could alter the carbon (C) and nitrogen (N) content of ecosystems, yet the magnitude of these effects are not well known. We examined C and N budgets of a subtropical woodland after 11 yr of exposure to elevated CO₂. We used open-top chambers to manipulate CO₂ during regrowth after fire, and measured C, N and tracer (15) N in ecosystem components throughout the experiment.

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The effects of elevated CO2 on ecosystem element stocks are equivocal, in part because cumulative effects of CO2 on element pools are difficult to detect. We conducted a complete above and belowground inventory of non-nitrogen macro- and micronutrient stocks in a subtropical woodland exposed to twice-ambient CO2 concentrations for 11 years. We analyzed a suite of nutrient elements and metals important for nutrient cycling in soils to a depth of ~2 m, in leaves and stems of the dominant oaks, in fine and coarse roots, and in litter.

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Adverse drug reactions continue to be a major cause of morbidity in both patients receiving therapeutics and in drug R&D programs. Predicting and possibly eliminating these adverse events remains a high priority in industry, government agencies and healthcare systems. With small molecule candidates, the fusion of nonclinical and clinical data is essential in establishing an overall system that creates a true translational science approach.

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Biomarkers are characteristics objectively measured and evaluated as indicators of: normal biologic processes, pathogenic processes, or pharmacologic response(s) to a therapeutic intervention. In environmental research and risk assessment, biomarkers are frequently referred to as indicators of human or environmental hazards. Discovering and implementing new biomarkers for toxicity caused by exposure to a chemical either from a therapeutic intervention or accidentally through the environment continues to be pursued through the use of animal models to predict potential human effects, from human studies (clinical or epidemiologic) or biobanked human samples, or the combination of all such approaches.

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Genome-wide RNA splicing (with gene expression) can be used to discover variations that drive specific diseases and / or change the susceptibility in individuals to drug responses including tissue specific toxicities. Evidence linking causative SNPs to individual splicing differences between individuals is emerging and this may lead to a better understanding of susceptibilities related to rare drug-induced toxicities. The development of more sensitive genomics tools is expected to further the study of variations in molecular phenotype from alternative splicing of pre-mRNA.

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Objective: The purpose of this study was to quantify interexaminer reliability of a standardized supine leg check procedure used to screen for leg-length inequality.

Methods: Two doctors of chiropractic used a standardized supine leg check procedure to examine 50 volunteers for leg-length inequality. The order of examination was randomized.

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Purpose: Strictures of the esophagus in children may have multiple etiologies including congenital, inflammatory, infectious, caustic ingestion, and gastroesophageal reflux (peptic stricture [PS]). Current literature lacks good data documenting long-term outcomes in children. This makes it difficult to counsel some patients about realistic treatment expectations.

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A series of N-substituted 3-(4-piperidinyl)-1,3-benzoxazolinones and oxindoles are reported which were found to be potent and selective muscarinic M1 agonists. By control of the physicochemical characteristics of the series, particularly the lipophilicity, compounds with good metabolic stability and excellent brain penetration were identified. An exemplar of the series was shown to be pro-cognitive in the novel object recognition rat model of temporal induced memory deficit.

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Background: Clinical variables may identify a subset of patients with pediatric-onset ulcerative colitis (UC) (≤18 years at diagnosis) at risk for adverse outcomes. We postulated that routinely measured clinical variables measured at diagnosis would predict colectomy in patients with pediatric-onset UC.

Methods: We conducted a chart review of patients with pediatric-onset UC at a single center over a 10-year period.

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First-in-human dose-selection criteria for biotherapeutics are changing, primarily based on severe adverse events in a single monoclonal antibody trial in healthy volunteers. Spurred by new EMA guidance, the minimum anticipated biological-effect level (MABEL) for estimating a starting human dose from exposure-response preclinical data have been introduced and should help to create long overdue target mechanism-based models focused on exposure-response relationships. Even though clarity of its application is still developing, this has the potential to become the model for most biotherapeutics in the future.

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Traditional Chinese medicine (TCM) is a holistic approach to health that attempts to bring the body, mind and spirit into harmony. TCM is an essential part of the healthcare system in several Asian countries, and is considered a complementary or alternative medical system in most Western countries. An integration of the traditional Chinese and Western systems of medicine has begun in multiple medical centers internationally, and there is increasing evidence that several herbs and combinations of herbs used in TCM impart important pharmacological effects.

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