Publications by authors named "Wearn J"

Because of the prevalence of extreme obesity in the United States, there has been an increase in prevalence of obesity hypoventilation syndrome (OHS). There is limited information on the characteristics and pattern of positive airway pressure (PAP) adherence in patients with OHS compared with eucapnic patients with obstructive sleep apnea (OSA). This article discusses in detail the impact of PAP therapy on outcomes in patients with OHS, compares adherence between continuous PAP and noninvasive ventilation in OHS, and compares PAP adherence in patients with OHS to patients with moderate to severe OSA enrolled in clinical trials designed to improve CPAP adherence.

View Article and Find Full Text PDF

Thyrotropin releasing hormone (TRH)-stimulation testing for pituitary pars intermedia dysfunction (PPID) in horses is only recommended at certain times of the year. Current diagnostic cut-off values reflect testing in the northern hemisphere during this time. The aims of this study were to evaluate TRH stimulation testing during two different phases of the circannual pituitary cycle and to determine whether diagnostic cut-off values developed in the northern hemisphere are appropriate in Australia.

View Article and Find Full Text PDF

Background: Longitudinal evaluation of plasma endogenous ACTH concentration in clinically normal horses has not been investigated in the Southern Hemisphere.

Objectives: To longitudinally determine monthly upper reference limits for plasma ACTH in 2 disparate Australian geographic locations and to examine whether location affected the circannual rhythm of endogenous ACTH in the 2 groups of horses over a 12-month period.

Animals: Clinically normal horses <20 years of age from 4 properties (institutional herd and client owned animals) in Perth (n = 40) and Townsville (n = 41) were included in the study.

View Article and Find Full Text PDF

Reasons For Performing Study: Recurrent laryngeal neuropathy (RLN) causes airway obstruction and adversely affects racing performance in Thoroughbred racehorses. Prosthetic laryngoplasty (PL) is the preferred treatment of RLN as it returns variables of airway mechanics to baseline. A number of materials have been evaluated as prostheses; however, the application of Lycra has not been rigorously investigated.

View Article and Find Full Text PDF

Equine metabolic syndrome (EMS) is a condition of obese horses characterized by insulin resistance, systemic inflammation, and an increased risk of laminitis. The pathogenesis of EMS is thought, in part, to be due to inflammatory proteins produced by adipose tissue. Reducing inflammation may decrease the incidence of laminitis in horses with EMS.

View Article and Find Full Text PDF

Foliar endophytic fungi appear to be ubiquitous in nature, occurring in a very wide range of herbaceous plants. However, their ecological role within forbs is very poorly known and interactions with foliar-feeding insects virtually unexplored. In this study, leaves of Cirsium arvense were infected with different combinations of endophyte fungi that had been previously isolated from this plant species.

View Article and Find Full Text PDF

Pioglitazone is a thiazolidinedione class of antidiabetic agent with proven efficacy in increasing insulin sensitivity in humans with noninsulin-dependent diabetes mellitus, a syndrome of insulin resistance sharing similarities with equine metabolic syndrome. The purpose of this study was to determine the pharmacokinetics of pioglitazone in adult horses following multiple oral dose administration. Pioglitazone hydrochloride (1 mg/kg) was administered orally for 11 doses at 24-h intervals, and plasma samples were collected.

View Article and Find Full Text PDF

Background: Obesity and insulin resistance increase the risk of laminitis in horses. Pioglitazone (PG) is an insulin-sensitizing drug used in humans that is absorbed after oral administration to horses.

Hypothesis: PG treatment will increase insulin sensitivity and transcript abundance of glucose and lipid transporters in adipose and skeletal muscle tissues.

View Article and Find Full Text PDF

The lipogenic capacities of equine liver and adipose tissue explants were investigated in vitro. Preference for glucose or acetate as the primary carbon source for de novo fatty acid synthesis was determined using (14)C labeled substrates. Additional aims included determining the relative contribution of NADPH generating pathways to reducing equivalent generation and comparing the lipogenic activity of two adipose depots, mesenteric and subcutaneous harvested from the crest region of the neck.

View Article and Find Full Text PDF

Arbuscular mycorrhizal fungi (AMF) play a vital role in ecosystem functioning. In most grasslands, herbivory by both vertebrate and invertebrate herbivores is common and thus in order to assess herbivore effects on multitrophic-level interactions both should be considered. This study investigated the effects of grazing by rabbit and insect herbivores on root-colonization of grasses by AMF in two lowland grasslands in southern England, UK.

View Article and Find Full Text PDF

The following address was given at the Gold-Headed Cane Ceremony, University of California School of Medicine, on 3 June 1966. At this event on the eve of Commencement Day, the senior student who has been chosen by his classmates and professors in the Department of Medicine as the one who best exemplifies the qualities of a true physician is given a gold-headed cane. This carries on the English tradition of a cane which was passed from physician to physician from 1689 to 1825, and was carried successively by Drs.

View Article and Find Full Text PDF