Publications by authors named "Danielle M Fitzgerald"

Article Synopsis
  • High levels of insulin in horses and ponies can lead to acute laminitis, especially in those with insulin dysregulation who respond strongly to carbohydrate-rich diets.
  • The study investigated whether blocking the GLP-1 receptor would reduce insulin spikes after a high glycemic meal in ponies by administering a blocking peptide and measuring insulin and glucose levels.
  • Results indicated that while blood glucose and GLP-1 levels remained unchanged, blocking the GLP-1 receptor significantly lowered the overall insulin response, suggesting a potential method for managing acute insulin spikes.
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Background: Active glucagon-like peptide-1 (aGLP-1) has been implicated in the pathogenesis of equine insulin dysregulation (ID), but its role is unclear. Cleavage of proglucagon (coded by the GCG gene) produces aGLP-1 in enteral L cells.

Objectives: The aim in vivo was to examine the sequence of the exons of GCG in horses with and without ID, where aGLP-1 was higher in the group with ID.

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Background: Gastrointestinal peptides, such as glucagon-like peptide-2 (GLP-2), could play a direct role in the development of equine hyperinsulinaemia.

Objectives: To describe the secretory pattern of endogenous GLP-2 over 24 h in healthy ponies and determine whether oral administration of a synthetic GLP-2 peptide increases blood glucose or insulin responses to feeding.

Study Design: A cohort study followed by a randomised, controlled, cross-over study.

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We report the synthesis of block copolymers of monomethoxylated polyethylene glycol and poly(glycerol carbonate) (mPEG--PGC) via the ring-opening polymerization of benzyl glycidyl ether, monomethoxylated polyethylene glycol, and carbon dioxide using a cobalt salen catalyst. The resulting block copolymers display high polymer/cyclic carbonate selectivity (>99%) and, if two oxirane monomers are used, random incorporation into the polymer feed. The resulting diblock mPEG--PGC polymer shows promise as a nanocarrier for surfactant-free, sustained chemotherapeutic delivery.

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Pressure sensitive adhesives are components of everyday products found in homes, offices, industries, and hospitals. Serving the general purpose of fissure repair and object fixation, pressure sensitive adhesives indiscriminately bind surfaces, as long as contact pressure is administered at application. With that being said, the chemical and material properties of the adhesive formulation define the strength of a pressure sensitive adhesive to a particular surface.

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Pressure sensitive adhesives are familiar household items spanning applications in everyday repair, office supplies, and topical wound care. Through innovations in material and polymer science, pressure sensitive adhesives will advance from current commodity to novel specialty materials with resulting new clinical uses and improved patient care.

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Equine insulin dysregulation (ID) comprises amplified insulin responses to oral carbohydrates or insulin resistance, or both, which leads to sustained or periodic hyperinsulinaemia. Hyperinsulinaemia is important in horses because of its clear association with laminitis risk, and the gravity of this common sequela justifies the need for a better understanding of insulin and glucose homoeostasis in this species. Post-prandial hyperinsulinaemia is the more commonly identified component of ID and is diagnosed using tests that include an assessment of the gastrointestinal tract (GIT).

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Background: Drug-loaded meshes offer a promising delivery strategy for the prevention of local recurrence. Patient-derived xenograft (PDX) models are representative of individual patient tumors and predictive of clinical outcomes.

Methods: A PDX model was established in NSG (NOD-scid IL2Rgamma) mice using tumor tissue from a patient with aggressive lung adenocarcinoma.

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Objective: To determine the effect of a starch-rich treat, added to the daily diet of ponies for 10 days, on enteroinsular responses to meal consumption.

Animals: 10 mixed-breed adult ponies owned by Queensland University of Technology were used in the study. Six ponies were metabolically healthy, and 4 were insulin dysregulated at the start of the study, according to the results of an in-feed oral glucose test.

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We describe the synthesis of poly(glycidyl acetate--glycidyl butyrate carbonate)s the terpolymerization of glycidyl acetate (GA), glycidyl butyrate (GB), and CO by a cobalt salen complex in high atom economy. These new non-cytotoxic polycarbonates are pressure-sensitive adhesives, and peel testing shows the adhesive strength ranges from Scotch-Tape® to hot-melt glues based on glycidyl butyrate content. The tunable adherence, benign degradation products, and facile application and removal suggest their utility as temporary adhesives, such as those used in biomedical applications or medical devices.

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The equine microbiome can change in response to dietary alteration and may play a role in insulin dysregulation. The aim of this study was to determine the effect of adding pasture to a hay diet on the faecal bacterial microbiome of both healthy and insulin-dysregulated ponies. Faecal samples were collected from 16 ponies before and after dietary change to enable bacterial 16S rRNA sequencing of the V3-V4 region.

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Background: The oral glucose test (OGT) is a useful tool for diagnosing insulin dysregulation (ID) and is somewhat repeatable in ponies under consistent management. This study aimed to determine whether the insulin and incretin responses to an OGT in ponies differed after short-term access to fertilised pasture, compared to unfertilised pasture, by using a randomised, repeated measures study design. Sixteen mixed-breed ponies were classified as severely insulin-dysregulated (SD; post-prandial insulin ≥80 μIU/mL) or not severely insulin-dysregulated (NSD; post-prandial insulin < 80 μIU/mL) using an OGT prior to the study.

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Generalized obesity, regional adiposity, hyperinsulinemia and hypertriglyceridemia are all potential indicators of equine metabolic syndrome (EMS). This study aimed to assess the relationship between morphometric measurements of body condition and metabolic hormone concentrations in ponies, with and without a neck crest or generalised obesity. Twenty-six ponies were assigned a body condition score (BCS) and cresty neck score (CNS).

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Background: Supraphysiological insulin and incretin responses to a cereal-based diet have been described in horses and ponies with insulin dysregulation (ID). However, the hormonal responses to grazing have not yet been described.

Objectives: To determine if there is a difference in the insulin and incretin responses to grazing pasture between insulin-dysregulated and healthy ponies.

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