Publications by authors named "McKechnie A"

Conventionally, the size, shape, and biomechanics of cartilages are determined by their voluminous extracellular matrix. By contrast, we found that multiple murine cartilages consist of lipid-filled cells called lipochondrocytes. Despite resembling adipocytes, lipochondrocytes were molecularly distinct and produced lipids exclusively through de novo lipogenesis.

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Introduction: Glucagon-like peptide-1 receptor agonists, dual glucose-dependent insulinotropic peptide receptor agonists and sodium-glucose cotransporter-2 inhibitors are used increasingly in patients receiving peri-operative care. These drugs may be associated with risks of peri-operative pulmonary aspiration or euglycaemic ketoacidosis. We produced a consensus statement for the peri-operative management of adults taking these drugs.

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Intubation in patients living with obesity poses unique challenges due to altered airway anatomy and reduced physiological reserve, increasing the risk of complications. In synthesizing evidence from multiple trials, our meta-analysis suggests that videolaryngoscopy may provide a higher likelihood of achieving successful intubation on the first attempt compared to direct laryngoscopy while not substantially increasing the procedure time. Videolaryngoscopy was associated with a significant increase in first-pass intubation success compared to direct laryngoscopy, with a pooled risk ratio (RR) of 0.

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Accurately predicting exposure of animals to climate change requires evaluating the effects of warming on the microclimates they occupy. Birds, like many other taxa, make extensive use of cool microsites in vegetation during hot weather. Taking advantage of recent advances in modelling tree canopy microclimates, we combined LiDAR-based individual tree canopy mapping and biophysical modelling to evaluate the current and future availability of cool microsites in a subtropical African savanna landscape.

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Heat loss across the beak is an important thermoregulatory mechanism among birds, particularly in large-beaked taxa such as toucans (Ramphastidae) and hornbills (Bucerotidae). The number of species investigated remains limited, as does our understanding of how the functional significance of this pathway varies with environmental variables such as humidity, with little previous research on species inhabiting humid environments. We used infrared thermography to test the hypothesis that large (600-1300 g) Afrotropical forest hornbills use their beaks and casques as thermal radiators.

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Subterranean mammals representing a single subspecies occurring along an aridity gradient provide an appropriate model for investigating adaptive variation in thermal physiology with varying levels of precipitation and air temperature. This study examined the thermal physiological adaptations of common mole-rats (Cryptomys hottentotus hottentotus) across five populations along an aridity gradient, challenging the expectation that increased aridity would lead to reduced metabolic rate, lower body temperatures and broader thermoneutral zones. No significant, consistent differences in metabolic rate, body temperature or thermal conductance were observed between populations, suggesting uniform thermoregulatory mechanisms across habitats.

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Hypometabolism arising from active metabolic suppression occurs in several contexts among endotherms, particularly during heterothermic states such as torpor. However, observed Q ≈ 1 for avian resting metabolic rate within the thermoneutral zone, values far below the Q = 2-3 expected on the basis of Arrhenius effects, suggests hypometabolism also plays a role in birds' thermoregulation at environmental temperatures approaching or exceeding normothermic body temperature (T). We evaluated the occurrence of hypometabolism during heat exposure among birds by re-analysing literature data to quantify changes in T and resting metabolic rate (RMR) near the upper boundary of the thermoneutral zone, at air temperatures (T) between the inflection above which T increases above normothermic levels (T) and the upper critical limit of thermoneutrality (T).

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Many of the negative physiological effects of lead involve the hypothalamus, but the possibility that thermoregulation is affected has received little attention. We tested the hypothesis that lead exposure reduces avian thermoregulatory performance under hot conditions in pied crows (Corvus albus) experimentally exposed to lead in their diet. Crows in our high lead treatment (blood [Pb] = 87.

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Respirometry is an important tool for understanding whole-animal energy and water balance in relation to the environment. Consequently, the growing number of studies using respirometry over the last decade warrants reliable reporting and data sharing for effective dissemination and research synthesis. We provide a checklist guideline on five key sections to facilitate the transparency, reproducibility, and replicability of respirometry studies: 1) materials, set up, plumbing, 2) subject conditions/maintenance, 3) measurement conditions, 4) data processing, and 5) data reporting and statistics, each with explanations and example studies.

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Human milk improves neurodevelopment for preterm infants, but relationships between human milk and neurodevelopment for infants with critical CHD are unknown. We aimed to (1) explore associations between human milk/direct breastfeeding and neurodevelopment at 1-year and 2-year follow-up and (2) describe patterns of human milk (maternal, donor) and commercial formula during hospitalisation in the first year of life.This retrospective cohort study included infants who underwent surgery for CHD < 6 months old.

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The role of atmospheric humidity in the evolution of endotherms' thermoregulatory performance remains largely unexplored, despite the fact that elevated humidity is known to impede evaporative cooling capacity. Using a phylogenetically informed comparative framework, we tested the hypothesis that pronounced hyperthermia tolerance among birds occupying humid lowlands evolved to reduce the impact of humidity-impeded scope for evaporative heat dissipation by comparing heat tolerance limits (HTLs; maximum tolerable air temperature), maximum body temperatures (Tmax), and associated thermoregulatory variables in humid (19.2 g HO m) versus dry (1.

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Aim: To synthesize the literature on breastfeeding outcomes associated with exposure to internationally recognized best practices, such as the Baby-Friendly Hospital Initiative, for patients in the United States during the postpartum period, contextualized within the Missed Care Model.

Design: The authors employed Whittemore and Knafl's integrative review framework and the 2020 PRISMA guidelines for data extraction, synthesis, reporting and assessment.

Methods: Five electronic databases were searched for articles published between 2007 and 2023.

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Background: Following prenatal diagnosis of critical congenital heart disease (CCHD), parents encounter emotional distress while facing caregiving challenges. Supportive psycho-educational interventions using mobile health (mHealth) can make care more accessible.

Objectives: We tested a novel nurse-guided mHealth care program, Preparing Heart and Mind (PHM), with the objectives of examining feasibility and estimating the effect of the intervention on parents' emotional distress.

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Although the prevalence of lead poisoning in southern Africa's Gyps vultures is now well-established, its finer physiological effects on these endangered species remain poorly characterised. We evaluated the sub-lethal impact of acute lead exposure on Cape and White-backed Vulture chicks from two breeding colonies in South Africa, by analysing its possible effects on key blood biochemistry parameters, immune function, packed cell volume and δ-aminolevulinic acid dehydratase (δ-ALAD) activity. All 37 White-backed Vulture nestlings sampled displayed elevated lead levels (>10 μg/dL), and seven had blood [Pb] >100 μg/dL.

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Under climate change, increasing air temperature average and variability pose substantial thermal challenges to animals. While plasticity in thermoregulatory traits could potentially attenuate this impact, whether thermal acclimatisation can occur quickly enough to track weather variability in hot climates is unknown in any endotherm, and sex differences have never been tested. We investigated acclimatisation responsiveness of male and female wild zebra finches to short-term (< 2 weeks) summer temperature fluctuations in the Australian desert.

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Article Synopsis
  • The Preparing Heart and Mind™ (PHM™) care program aims to support parents facing the prenatal diagnosis of critical congenital heart disease (CCHD) by addressing their concerns and improving caregiving skills.
  • A nurse-guided mHealth intervention was piloted with parents, revealing that mental health and condition-specific information were the primary focus areas, along with developing specific caregiving skills.
  • The program highlights the critical need for mental health assessments and emphasizes the importance of addressing caregiving challenges and uncertainties during the prenatal period.
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Background Infants with single ventricle congenital heart disease undergo 3 staged surgeries/interventions, with risk for morbidity and mortality. We estimated the effect of human milk (HM) and direct breastfeeding on outcomes including necrotizing enterocolitis, infection-related complications, length of stay, and mortality. Methods and Results We analyzed the National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) registry (2016-2021), examining HM/breastfeeding groups during stage 1 and stage 2 palliations.

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Survival and reproduction of endotherms depend on their ability to balance energy and water exchange with their environment, avoiding lethal deficits and maximising gains for growth and reproduction. At high environmental temperatures, diurnal endotherms maintain body temperature (Tb) below lethal limits via physiological and behavioural adjustments. Accurate models of these processes are crucial for predicting effects of climate variability on avifauna.

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Objective: To identify factors that support or limit human milk (HM) feeding and direct breastfeeding (BF) for infants with single ventricle congenital heart disease at neonatal stage 1 palliation (S1P) discharge and at stage 2 palliation (S2P) (∼4-6 months old).

Study Design: Analysis of the National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) registry (2016-2021; 67 sites). Primary outcomes were any HM, exclusive HM, and any direct BF at S1P discharge and at S2P.

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Reversible phenotypic flexibility allows organisms to better match phenotypes to prevailing environmental conditions and may produce fitness benefits. Costs and constraints of phenotypic flexibility may limit the capacity for flexible responses but are not well understood nor documented. Costs could include expenses associated with maintaining the flexible system or with generating the flexible response.

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Background: Infants with single ventricle (SV) congenital heart disease (CHD) undergo three staged surgeries/interventions, with risk for morbidity and mortality. We estimated the effect of human milk (HM) and direct breastfeeding (BF) on outcomes including necrotizing enterocolitis (NEC), infection-related complications, length of stay (LOS), and mortality.

Methods: We analyzed the National Pediatric Cardiology Quality Improvement Collaborative registry (2016-2021), examining HM/BF groups during stage 1 (S1P) and stage 2 (S2P) palliations.

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Many birds reduce rest-phase energy demands through heterothermy, physiological responses involving facultative, reversible reductions in metabolic rate and body temperature (Tb). Here, we review the phylogenetic distribution and ecological contexts of avian heterothermy. Heterothermy has been reported in 140 species representing 15 orders and 39 families.

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Infants with single-ventricle (SV) congenital heart disease (CHD) undergo staged surgical and/or catheter-based palliation and commonly experience feeding challenges and poor growth. Little is known about human milk (HM) feeding or direct breastfeeding (BF) in this population. To determine (1) HM and BF prevalence for infants with SV CHD, and (2) whether BF at neonatal stage 1 palliation (S1P) discharge is associated with any HM at stage 2 palliation (S2P; ∼4-6 months old).

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