Publications by authors named "Tim Quinn"

Vitamin A plays a prominent role for maintaining optimal bone status, but its impact upon the bone in response to vitamin A deficiency is not well defined. The purpose of this study was to evaluate how replenishing vitamin A by either whole food cod liver oil (COD) or the active metabolite of vitamin A, retinoic acid (RA), altered bone thickness of vitamin A-deficient (VAD) rats. Weanling rats were administered a control diet (CTRL) or VAD diet for 9 weeks.

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Autoimmune gastritis is an organ-specific autoimmune disease of the stomach associated with pernicious anemia. The previous work from us and other groups identified MCPIP1 as an essential factor controlling inflammation and immune homeostasis. MCPIP1(-/-) developed severe anemia.

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Previous studies using MCP-induced protein 1 (MCPIP1)/Zc3h12a-deficient mice suggest that MCPIP1 is an important regulator of inflammation and immune homeostasis. However, the characterization of the immunological phenotype of MCPIP1-deficient mice has not been detailed. In this study, we performed evaluation through histological, flow cytometric, enzyme-linked immunosorbent assay and real-time PCR analysis and found that targeted disruption of MCPIP1 gene leads to fatal, highly aggressive and widespread immune-related lesions.

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Exenatide or Exendin-4 is a 39-amino acid agonist of the glucagon like peptide (GLP-1) receptor approved for the adjunctive treatment for type 2 diabetes. Recent reports suggest that GLP-1 agonists may also have distant effects including C-cell thyroid hyperplasia. The aim of this study was to evaluate the effect of exendin-4 on the thyroid and parathyroid cells in a rat model.

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Toll-like receptors (TLR) are pivotal in macrophage activation. The molecular mechanisms controlling TLR signaling and macrophage activation are not completely understood. Zc3h12d is originally identified as a possible tumor suppressor gene.

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It is unclear how stress granule (SG) formation and cellular apoptosis are coordinately regulated. MCPIP1 (monocyte chemotactic protein-induced protein 1), also known as Zc3h12a, is a critical regulator of the inflammatory response and immune homeostasis. However, the role of MCPIP1 in stress response remains unknown.

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Background: Nonalcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease in the Western world. The aim of this study was to evaluate the biochemical and histological effects of omega-3 fatty acid and exendin-4 treatment on NAFLD in an animal model.

Methods: Sixty-three 8-week-old outbred Sprague-Dawley male rats were used for this study.

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The pathophysiology of Fat Embolism Syndrome (FES) is poorly understood and subject to some controversy. Evaluation of the evolution of histological changes in the lungs of patients with FES is impractical. The current theories of FES were established through acute clinical observations and acute animal experiments, but sequential changes in the histology of lungs over a prolonged period have not been made.

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The non-iridescent structural colours of avian feather barbs are produced by coherent light scattering from amorphous (i.e. quasi-ordered) nanostructures of beta-keratin and air in the medullary cells of feather barb rami.

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Purpose: The purpose of this manuscript is to investigate the presence of nucleoside/nucleotide efflux transporter in cornea and to evaluate the role in ocular drug efflux.

Methods: RT-PCR, immunoprecipitation followed by Western blot analysis and immunostaining were employed to establish molecular presence of multidrug resistance associated protein 5 (MRP5) on cornea. Corneal efflux by MRP5 was studied with bis(POM)-PMEA and acyclovir using rabbit and human corneal epithelial cells along with MRP5 over expressing cells (MDCKII-MRP5).

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High intensity focused ultrasound (HIFU) is generally thought to interact with biological tissues in two ways: hyperthermia (heat) and acoustic cavitation. Pulsed mode HIFU has recently been demonstrated to increase the efficacy of a variety of drug therapies. Generally, it is presumed that the treatment acts to temporarily increase the permeability of the tissue to the therapeutic agent, however, the precise mechanism remains in dispute.

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Infection with Mycobacterium tuberculosis (TB) induces pulmonary immunopathology mediated by classical Th1 type of acquired immunity with hepatic involvement in up to 80% of disseminated cases. Since PPAR agonists cause immune responses characterized by a decrease in the secretion of Th1 cytokines, we investigated the impact of activating these receptors on hepatic pathology associated with a well-characterized model of Th1-type pulmonary response. Male Fischer 344 rats were either maintained on a drug-free diet (groups I and II), or a diet containing diethylhexylphthalate (DEHP), a compound transformed in vivo to metabolites known to activate PPARs, for 21 days (groups III and IV).

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The spontaneously epileptic rat (SER), a double mutant (zi/zi, tm/tm), exhibits both tonic convulsions and absence-like seizures from the age of 8 weeks. Since the first point mutation in the voltage-gated sodium channel (VGSC) beta(1) subunit in human generalized epilepsy with febrile seizures plus (GEFS+) was identified, more and more types of genetic epilepsy have been causally suggested to be related to gene changes in VGSC. However, there are no reports that can elucidate the effects of VGSC in SER.

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Cornea is considered as a major barrier for ocular drug delivery. Low ocular bioavailability of drugs has been attributed primarily to low permeability across corneal epithelium, thus leading to sub-therapeutic concentrations of drug in the eye and treatment failure. The role of drug efflux proteins, particularly the P-glycoprotein (P-gp) in ocular drug bioavailability has been reported.

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The structural colours of butterflies and moths (Lepidoptera) have been attributed to a diversity of physical mechanisms, including multilayer interference, diffraction, Bragg scattering, Tyndall scattering and Rayleigh scattering. We used fibre optic spectrophotometry, transmission electron microscopy (TEM) and 2D Fourier analysis to investigate the physical mechanisms of structural colour production in twelve lepidopteran species from four families, representing all of the previously proposed anatomical and optical classes of butterfly nanostructure. The 2D Fourier analyses of TEMs of colour producing butterfly scales document that all species are appropriately nanostructured to produce visible colours by coherent scattering, i.

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Bronchiolitis obliterans (BOS - bronchiolitis obliterans syndrome - clinical diagnosis; CBO-histopathologic diagnosis), is a chronic disease process of fibrosis and cellular deposition in airways, complicating long term survival following lung transplantation. BOS is also the result of sporadic toxicant exposure, with airway signs, symptoms, and histology indistinguishable from allograft rejection. This study establishes a transplant BOS model in MHC-mismatched rats and compares their cytokine profiles and histopathology to that of our established toxicant-induced BOS model.

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Objectives: To determine if differences in drug-related Staphylococcus aureus killing, associated in vivo with neutropenia, is neutrophil-related in vitro, and the mechanisms of this interaction.

Methods: To evaluate the influence of living neutrophils on drug-S. aureus interactions, cell wall enzymes, the PBPs, were isolated and their binding to five (beta lactam and other) antibiotics was evaluated following incubation (or not) with neutrophils.

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Mycobacterial infection occurs frequently in patients that receive protease inhibitors, which are drugs used to treat AIDS, but are known for metabolic effects. Proteases of microbial antigens have been recognized as important regulators of host inflammation and cellular response. To evaluate protease inhibitor effect on a mycobacterial infection, a pilot animal model was established.

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