Publications by authors named "Christopher Courtney"

Background And Objectives: , the causative agent of histomonosis (i.e., blackhead disease), threatens the poultry industry with serious economic losses due to its high mortality and morbidity in turkey and chicken flocks.

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  • The rise of e-cigarette use among teens and young adults has led to serious public health concerns, particularly regarding chronic gut inflammation caused by vaping.
  • Chronic vaping produces hydrogen sulfide, which can worsen health issues for people living with HIV by affecting metabolism and increasing susceptibility to diseases.
  • A study using advanced metabolomics on PWH who vape or smoke revealed significant changes in metabolic profiles, highlighting new biochemical links and the need to understand the health risks of vaping on this vulnerable population.
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Femur head necrosis (FHN), also known as bacterial chondronecrosis with osteomyelitis (BCO), has remained an animal welfare and production concern for modern broilers regardless of efforts to select against it in primary breeder flocks. Characterized by the bacterial infection of weak bone, FHN has been found in birds without clinical lameness and remains only detectable via necropsy. This presents an opportunity to utilize untargeted metabolomics to elucidate potential non-invasive biomarkers and key causative pathways involved in FHN pathology.

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Histamine is involved in the regulation of immune response, vasodilation, neurotransmission, and gastric acid secretion. Although elevated histamine levels and increased expression of histamine metabolizing enzymes have been reported in renal disease, there is a gap in knowledge regarding the mechanisms of histamine-related pathways in the kidney. We report here that all four histamine receptors as well as enzymes responsible for the metabolism of histamine are expressed in human and rat kidney tissues.

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Bone tissue engineering is an emerging field of regenerative medicine, with a wide array of biomaterial technologies and therapeutics employed. However, it is difficult to objectively compare these various treatments during various stages of tissue response. Metabolomics is rapidly emerging as a powerful analytical tool to establish broad-spectrum metabolic signatures for a target biological system.

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Bacterial growth substrates influence a variety of biological functions, including the biosynthesis and regulation of lipid intermediates. The extent of this rewiring is not well understood nor has it been considered in the context of virally infected cells. Here, we used a one-host-two-temperate phage model system to probe the combined influence of growth substrate and phage infection on host carbon and lipid metabolism.

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Heat stress (HS) is devastating to poultry production sustainability worldwide. In addition to its adverse effects on growth, welfare, meat quality, and mortality, HS alters the gut integrity, leading to dysbiosis and leaky gut syndrome; however, the underlying mechanisms are not fully defined. Here, we used a high-throughput mass spectrometric metabolomics approach to probe the metabolite profile in the duodenum of modern broilers exposed to acute (AHS, 2 h) or chronic cyclic (CHS, 8 h/day for 2 weeks) HS in comparison with thermoneutral (TN) and pair-fed birds.

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  • Microbial communities in natural settings are difficult to replicate in lab experiments due to "bottle effects," which refer to unexpected changes when samples are enclosed in experimental containers.
  • A study during a 2019 Lake Erie cyanobacterial bloom showed that nutrient availability significantly affected the activity of heterotrophic bacteria and the expression of phage, revealing alterations in the microbiome that are often overlooked.
  • Variability between sample replicates indicated that phage activity not only influenced the dynamics of the microbial community but also correlated with important functional genes and metabolites, offering new insights into virus-host interactions in natural ecosystems.
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Muscle builders frequently consume protein supplements, but little is known about their effect on the gut microbiota. This study compared the gut microbiome and metabolome of self-identified muscle builders who did or did not report consuming a protein supplement. Twenty-two participants (14 males and 8 females) consumed a protein supplement (PS), and seventeen participants (12 males and 5 females) did not (No PS).

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Recent scientific evidence suggests that traits energy and fatigue are two unique unipolar moods with distinct mental and physical components. This exploratory study investigated the correlation between mental energy (ME), mental fatigue (MF), physical energy (PE), physical fatigue (PF), and the gut microbiome. The four moods were assessed by survey, and the gut microbiome and metabolome were determined from 16 S rRNA analysis and untargeted metabolomics analysis, respectively.

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Essential, conserved cellular processes depend not only on essential, strictly conserved proteins but also on essential proteins that evolve rapidly. To probe this poorly understood paradox, we exploited the rapidly evolving telomere-binding protein, /HOAP, which protects chromosomes from lethal end-to-end fusions. We replaced the HOAP with a highly diverged version from its close relative, .

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Unlabelled: IntroductionInterventions to reduce disability from acute orthopedic injuries require a primary assessment of knowledge and need. There are no previous studies to assess this need in the remote provincial islands of the Philippines, an area recurrently affected by natural disaster.ProblemA preliminary assessment of orthopedic knowledge and need was performed to be expanded for regional or national implementation.

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Background: Numerous studies have demonstrated that the Paced Auditory Serial Addition Test (PASAT) has utility for the detection of cognitive processing deficits. While the PASAT has demonstrated high levels of internal consistency and test-retest reliability, administration of the PASAT has been known to create undue anxiety and frustration in participants. As a result, degradation of performance may be found on the PASAT.

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The fingers and feet have long been accepted as optimal anatomical recording sites for electrodermal activity. The available literature suggests that the feet are more responsive than the fingers. The present report compared skin conductance level (SCL) and responses (SCRs) from the left foot and the distal phalanges of the fingers on the nondominant hand among 19 participants.

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The current project is a preliminary attempt at assessing the potential of a three-dimensional virtual reality Stroop task (VRST) for investigation of supervisory attentional processing. The VRST was compared with paper-and-pencil and computer automated (two-dimensional) versions of the Stroop. Psychophysiological measures were also used to assess varying levels of user arousal.

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Most evidence suggests that awareness of the CS-US contingency is necessary for human autonomic conditioning. However, Schultz and Helmstetter (2010) reported unaware skin conductance conditioning using difficult-to-discriminate visual CSs. We sought to replicate these findings with procedures nearly identical to Schultz and Helmstetter among 66 participants.

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Aim: To compare the effectiveness of group follow-up with individual follow-up after participation in the Dose Adjustment for Normal Eating (DAFNE) structured education programme.

Methods: Cluster randomised controlled trial involving 437 adults with type 1 diabetes attending hospital diabetes clinics in Ireland. All participants received DAFNE at baseline.

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Virtual environments provide the ability to systematically deliver test stimuli in simulated contexts relevant to real world behavior. The current study evaluated the validity of the Virtual Reality Stroop Task (VRST), which presents test stimuli during a virtual reality military convoy with simulated combat threats. Active duty Army personnel (N = 49) took the VRST, a customized version of the Automated Neuropsychological Assessment Metrics (ANAM)-Fourth Edition TBI Battery (2007) that included the addition of the ANAM Stroop and Tower tests, and traditional neuropsychological measures, including the Delis-Kaplan Executive Function System version of the Color-Word Interference Test.

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The assessment and treatment of traumatic brain injury (TBI) has become a difficult challenge for the DoD medical health system. Clinical neuropsychologists are being asked to make statements regarding a soldier's functional skills, ability to return to active duty, and competence in tasks of community living. Given the increasing prevalence of blast injuries to the head, and the fact that many brain injuries may have no external marker of injury, there is need for researching innovative assessment methods in detecting blast-related brain injury.

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Previous studies reveal age by valence interactions in attention and memory, such that older adults focus relatively more on positive and relatively less on negative stimuli than younger adults. In the current study, eyeblink startle response was used to measure differences in emotional reactivity to images that were equally arousing to both age groups. Viewing positive and negative pictures from the International Affective Picture System had opposite effects on startle modulation for older and younger adults.

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Given the prevalence of traumatic brain injury (TBI), and the fact that many mild TBIs have no external marker of injury, there is a pressing need for innovative assessment technology. The demand for assessment that goes beyond traditional paper-and-pencil testing has resulted in the use of automated cognitive testing for increased precision and efficiency; and the use of virtual environment technology for enhanced ecological validity and increased function-based assessment. To address these issues, a Virtual Reality Stroop Task (VRST) that involves the subject being immersed in a virtual Humvee as Stroop stimuli appear on the windshield was developed.

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As the popularity of virtual reality as an exposure therapy increases, it is important to validate the use of computer-generated stimuli in comparison to standardized images of "real" phobic objects, such as those of the International Affective Picture System (IAPS). The present study examined physiological and subjective measures of negative affect when viewing static IAPS images, static computer-generated images and moving videos of computer-generated images of feared stimuli and other negative stimuli which were not specifically feared. For example, a picture of a spider would be a "feared" stimulus for a spider fearful participant, whereas a picture of a snake would be categorized as a "negative" stimulus for that participant.

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Swimming in reduced electrophysiological preparations of the pteropod mollusc, Clione limacina, was blocked by bath application of hexamethonium even though pattern generator activity continued with this treatment. Neuromuscular recordings indicated that hexamethonium blocked synaptic input from Pd-3 and Pd-4 motoneurons to slow-twitch muscle cells, while connections from Pd-1A and Pd-2A motoneurons to fast-twitch muscle cells were variable in their response to hexamethonium-synaptic inputs were suppressed in most cases and occasionally blocked, but the latter only with high concentrations and long incubations. Acutely dissociated wing muscle cells showed a concentration-dependency in the percentage of contracted cells with bath application of acetylcholine, and this contractile activity was blocked in preparations that were first bathed in hexamethonium.

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There are wide individual differences in the ability to detect a stimulus contingency embedded in a complex paradigm. The present study used a cognitive masking paradigm to better understand individual differences related to contingency learning. Participants were assessed on measures of electrodermal arousal and on working memory capacity before engaging in the contingency learning task.

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