True grit? Comparative anatomy and evolution of gizzards in fishes.

Gut morphology frequently reflects the food organisms digest. Gizzards are organs of the gut found in archosaurs and fishes that mechanically reduce food to aid digestion. Gizzards are thought to compensate for edentulism and/or provide an advantage when consuming small, tough food items (e.g., phytoplankton and algae). It is unknown how widespread gizzards are in fishes and how similar these structures are among different lineages. Here, we investigate the distribution of gizzards across bony fishes to (1) survey different fishes for gizzard presence, (2) compare the histological structure of gizzards in three species, (3) estimate how often gizzards have evolved in fishes, and (4) explore whether anatomical and ecological traits like edentulism and microphagy predict gizzard presence. According to our analyses, gizzards are rare across bony fishes, evolving only six times in a broad taxonomic sampling of 51 species, and gizzard presence is not clearly correlated with factors like gut length or dentition. We find that gizzard morphology varies among the lineages where one is present, both macroscopically (presence of a crop) and microscopically (varying tissue types). We conclude that gizzards likely aid in the mechanical reduction of food in fishes that have lost an oral dentition in their evolutionary past; however, the relative scarcity of gizzards suggests they are just one of many possible solutions for processing tough, nutrient-poor food items. Gizzards have long been present in the evolutionary history of fishes, can be found in a wide variety of marine and freshwater clades, and likely have been overlooked in many taxa.

Cryoablation in 350 Nuss Procedures: Evolution of Hospital Length of Stay and Opioid Use.

INTRODUCTION: Current studies show cryoablation decreases opioid requirements and lengths of stay (LOS) in patients undergoing the Nuss procedure for pectus excavatum. This study evaluated the relationship between cryoablation and clinical outcomes for the Nuss procedure. METHODS: A retrospective single-center chart review was performed on patients undergoing the Nuss procedure with intercostal cryoablation from December 2017-August 2021. Demographics, hospital course, and postoperative complications were abstracted. To evaluate the evolution of outcomes over time, the earliest quarter (Q1) of cryoablation patients was compared to the last quarter (Q4). RESULTS: Over 45 months, 350 Nuss procedures with cryoablation were performed. The mean age at operation was 15.7 ± 2.3 years with an average Haller Index of 5.4 ± 4.2. The mean operative time was 136 ± 40.5 minutes. On average, patients used 2.8 ± 2.5 OME/kg of opioid in hospital with a LOS of 2.7 ± 1.1 days. The Q4 patients were discharged 1.3 days earlier (p<0.05) than Q1 patients, with 80% of Q4 discharged by postoperative day #2 vs. 23% in Q1 (p<0.05). Q4 patients received 74% (p<0.05) less opioid in hospital and 21% (p<0.05) less on discharge. Within 90 days postoperatively, complication rates (chest tube placement, wound infection, readmission, neuropathic pain) were similar. Only two patients (0.6%) required reoperation for bar migration/slippage. CONCLUSION: With increased experience, cryoablation for the Nuss procedure decreased opioid use by 74% and was associated with 80% of patients achieving early discharge. Major complication rates were not increased. Cryoablation can be successfully implemented as an effective method of postoperative analgesia. LEVEL OF EVIDENCE: Level III.

Intercostal Nerve Cryoablation in Minimally Invasive Repair of Pectus Excavatum: Effect on Pulmonary Function.

Introduction: Cryoablation of intercostal nerves is performed for pain control after minimally invasive repair of pectus excavatum (MIRPE). Cryoablation affects both sensory and motor neurons, resulting in temporary anesthesia to the chest wall and loss of intercostal motor function. The study objective is to determine the effect of cryoablation on incentive spirometry (IS) volumes, as a measure of pulmonary function, after MIRPE. Materials and Methods: A single-institution retrospective review of pediatric patients undergoing MIRPE was performed. All patients received a multimodal regimen (MMR) of analgesics postoperatively. Three groups were compared-cryoablation (CRYO), elastomeric pain pump (EPP), and MMR alone. The primary outcomes were postoperative IS volumes and IS volumes as a ratio of preoperative forced vital capacity (FVC). Secondary outcomes included pain scores, opioid use, length of stay (LOS), and infectious complications. Results: MIRPE was performed in 115 patients: 50 CRYO, 50 EPP, and 15 MMR alone. Groups were similar for demographics and pectus excavatum severity. Postoperative spirometry measurements were similar across groups: IS (CRYO 750 mL [500,961] versus EPP 750 mL [590,1019] versus MMR 696 mL [500,1037], P = .77); IS/FVC (CRYO 0.19 [0.14,0.26] versus EPP 0.20 [0.16,0.26] versus MMR 0.16 [0.15,0.24], P = .69). Although pain scores were also similar across groups, CRYO patients used less opioid (P < .05) and had shorter LOS (P < .05). Postoperative pneumonia was rare and similar across groups (P = 1.00). Conclusion: Intercostal nerve cryoablation during MIRPE does not adversely affect postoperative IS volumes or increase pneumonia rate, despite the temporary loss of motor innervation to intercostal muscles. Cryoablation provides effective pain control with less opioid use.

Ketone Ester Effects on Biomarkers of Brain Metabolism and Cognitive Performance in Cognitively Intact Adults ≥ 55 Years Old. A Study Protocol for a Double-Blinded Randomized Controlled Clinical Trial.

BACKGROUND: Ketone bodies have been proposed as an "energy rescue" for the Alzheimer's disease (AD) brain, which underutilizes glucose. Prior research has shown that oral ketone monoester (KME) safely induces robust ketosis in humans and has demonstrated cognitive-enhancing and pathology-reducing properties in animal models of AD. However, human evidence that KME may enhance brain ketone metabolism, improve cognitive performance and engage AD pathogenic cascades is scarce. OBJECTIVES: To investigate the effects of ketone monoester (KME) on brain metabolism, cognitive performance and AD pathogenic cascades in cognitively normal older adults with metabolic syndrome and therefore at higher risk for AD. DESIGN: Double-blinded randomized placebo-controlled clinical trial. SETTING: Clinical Unit of the National Institute on Aging, Baltimore, US. PARTICIPANTS: Fifty cognitively intact adults ≥ 55 years old, with metabolic syndrome. INTERVENTION: Drinks containing 25 g of KME or isocaloric placebo consumed three times daily for 28 days. OUTCOMES: Primary: concentration of beta-hydroxybutyrate (BHB) in precuneus measured with Magnetic Resonance Spectroscopy (MRS). Exploratory: plasma and urine BHB, multiple brain and muscle metabolites detected with MRS, cognition assessed with the PACC and NIH toolbox, biomarkers of AD and metabolic mediators in plasma extracellular vesicles, and stool microbiome. DISCUSSION: This is the first study to investigate the AD-biomarker and cognitive effects of KME in humans. Ketone monoester is safe, tolerable, induces robust ketosis, and animal studies indicate that it can modify AD pathology. By conducting a study of KME in a population at risk for AD, we hope to bridge the existing gap between pre-clinical evidence and the potential for brain-metabolic, pro-cognitive, and anti-Alzheimer's effects in humans.

Do You Need 'The Machine'? Tipping in Canada Is Unconscious (Part I).

Constantly on the lookout for Canadian mathematics education matters, I recently experienced a major personal tipping point. The juxtaposition of two different customer service situations was simply too much for me to handle. Now through the looking glass, it was abundantly clear that tipping in Canada is unconscious, and the evidence was everywhere. The current state of financial literacy education in Canadian schools, the opportunity that COVID-19 has provided for us to renew Canada's implied gratuity guidelines, and an investigation into pre- and post-tax bill totals all supported my assertion that the tipping culture in Canada is a habit in many senses of the word. A look back at how tipping in Canada has evolved from parting with a few coins every once and a while, and a look at the evolution of the point of sale terminal, which I refer to as 'The Machine', helped me realize that I am unable to move on and start looking for other Canadian mathematics education matters just yet. After all, if Canadian mathematics education matters, then Canadian mathematics education matters. As such, Part II of this article follows in the next issue. Stay tuned.

Toujours à l'affût en ce qui concerne l'enseignement des mathématiques au Canada, j'ai récemment atteint personnellement un véritable point de bascule. La combinaison de deux expériences différentes vécues en matière de service à la clientèle a tout simplement fait que je n'en pouvais plus. Vu de l'autre côté du miroir, donner un pourboire était de toute évidence un acte inconscient au Canada, un état de fait dont on peut voir des preuves partout. L'état actuel du programme d'éducation en littératie financière dans les écoles canadiennes, la possibilité que nous a donné la COVID-19 de renouveler les lignes de conduite tacites en ce qui a trait au pourboire ainsi qu'une enquête portant sur le total affiché sur les factures avant et après l'application de la taxe soutiennent tous mon affirmation selon laquelle la culture du pourboire est à bien des égards une habitude au Canada. Quand je regarde l'évolution de l'acte de donner du pourboire au Canada, passé du sacrifice occasionnel de quelques pièces de monnaie au terminal de point de vente, ce que j'appellerai « La Machine¼, je réalise que je ne peux pas encore passer à autre chose dans le domaine de l'enseignement des mathématiques. Après tout, si l'enseignement des mathématiques compte, celui-ci est donc important. À cet effet, lisez la deuxième partie de cet article dans le prochain numéro. À suivre.

Do You Need the Machine? Tipping in Canada Is Unconscious (Part II).

While recovering from a major personal tipping point (see Part I), I was still able to keep on the lookout for Canadian mathematics education matters. After all, if Canadian mathematics education matters, Canadian mathematics education matters. In doing so, I ran into a number of other financial problems. Everywhere I turned was a financial problem: from tipping in the sharing (or platform) economy; to spending your way to savings with credit cards; the proliferation of sportsbooks and online casinos; trying to reconcile the Canadian cost of living with the seemingly high accepted standard level of consumption; and the outrageous fee to take $20 out of my very own bank account. Each taken on their own, I clearly have some financial problems. Taken together, I contend that 'Egan's Financial Problems', albeit unconventional, could, one day, be the impetus for financial education and literacy leaving math class and becoming a class of its own in Canadian schools. Until then, I guess we go with the School of Hard Knocks for our financial education.

Alors que je me remets d'avoir atteint un important point de bascule personnel (voir la première partie), je fus tout de même en mesure de rester à l'affût en ce qui a trait à l'enseignement des mathématiques au Canada. Après tout, si les questions entourant l'enseignement des mathématiques au pays comptent, elles importent vraiment. Ce faisant, j'ai rencontré un certain nombre de problèmes d'ordre financier qui sont autres. Partout où je me tournais se trouvait un enjeu financier : qu'il s'agisse de donner un pourboire au sein d'une économie collaborative (ou axée sur les plateformes) ; à la gestion de l'épargne par le biais des cartes de crédit ; la prolifération de sites de paris sportifs et de casinos en ligne ; essayer de concilier le coût de la vie au Canada avec le niveau de consommation acceptable apparemment élevé ; et les frais exorbitants imposés pour encaisser 20 $ de mon propre compte de banque. En abordant ces aspects chacun séparément, il est clair que je vis certains problèmes financiers. Je soutiens que pris dans leur ensemble, les « problèmes financiers d'Egan ¼, bien que non conventionnels pourraient un jour donner lieu à une éducation et une littératie financière se distinguant des cours de mathématiques pour devenir un cours unique en son genre dans les écoles canadiennes. D'ici là, je me résigne à aller avec l'école de l'adversité en ce qui concerne notre éducation financière.

A multidisciplinary evaluation of suspected, non-confirmed cases of COVID-19 including chest CT, as compared to World Health Organization recommendations.

AIM: To report an audit of the evaluation of suspected, unconfirmed cases of COVID-19 including chest computed tomography (CT), as compared to World Health Organization recommendations. METHODS: A clinical audit was undertaken examining the evaluation of patients with suspected COVID-19 with negative SARS-CoV-2 reverse transcriptase polymerase chain reaction (RT-PCR) results, with comparison to WHO recommendations. A retrospective chart review was undertaken for 90 patients examining investigations, in particular CT, used to clarify the diagnosis. RESULTS: Ninety patients underwent additional investigation. Seventy-five per cent adherence to WHO recommendations was observed. Fifty-two men (57.78%) and 38 (42.22%) women were investigated, with a median age of 69 years (range 20-96 years). Seventy-nine chest CT examinations demonstrated positive, indeterminate, and negative rates for COVID-19 of 3.79%, 24.1%, and 72.15% respectively. Three patients had discordant swab results with initially negative and subsequently positive results for SARS-CoV-2, resulting in false-negative rates of 5.1% for those retested. Combining discordant RT-PCR swab results, positive radiology, and patients treated as COVID-19-positive due to indeterminate radiology and highly consistent symptoms, resulted in a false-negative rate for initial SARS-CoV-2 RT-PCR swabs of 16.67%. CONCLUSION: Seventy-five per cent compliance with relevant WHO guidance and a false-negative rate for initial swabs of 16.67% was demonstrated. Further evidence is needed to fully determine the utility of chest CT in the diagnosis of COVID-19 in the context of initial false-negative RT-PCR results.

An in vitro investigation of the survival and/or growth of Campylobacter jejuni in broiler digestate from different feed types.

Campylobacter spp. is the leading cause of bacterial gastroenteritis worldwide and poultry are the primary reservoir. The aim of this study was to investigate the survival and/or growth of Campylobacter jejuni NCTC 11168 in broiler digestate prepared from commercial starter, grower and finisher feed formulations. Bolton broth and digestates were prepared, inoculated with C. jejuni NCTC 11168 (approximately 3 log10 CFU per ml) and incubated under microaerobic conditions at 42°C for 24 h. Samples were taken at t = 0 (immediately after inoculation) and every 3 h thereafter, serially diluted and plated onto mCCDA. Campylobacter jejuni grew as expected in Bolton broth (control) reaching the early stationary phase after approximately 15 h. In contrast, although bacterial concentrations were maintained for at least 9 h, none of the feed digestates supported the growth of C. jejuni, which were not detected after 15 h. It is suggested that the nutrients available in the feed digestates are not enough to support C. jejuni growth and that additional factors may be at play in the avian gastrointestinal tract.

The Metre as a Metric: Canada's COVID-19 Conversion Kerfuffle.

As a Canadian mathematics educator, I have a vested interest in Canadian mathematics education matters. After all, to me, Canadian mathematics education matters. Knowing this little factoid, imagine my horror when it recently dawned on me that, no matter where I looked during this COVID-19 pandemic, all I saw was flippant treatment towards the metric system. As I detail in this article, COVID-19 social distancing signage, here in Canada, presents indifference towards the metric system. For shame, Canada. For shame. For the record, despite what nearly all the signs around us say at the moment, 2 m is not 6 ft. And, while I am at it, also for the record, 6 ft is not 2 m. Whether it is small business, big business or even the different levels of Canadian government (i.e., municipal, provincial or federal), it does not matter, the metric system is being poorly presented here at home during this global pandemic. The only good news, I am numb to it all now, which has helped me move on and start looking for other Canadian mathematics education matters. Stay tuned.

En tant qu'enseignant canadien des mathématiques, tout ce qui a trait à l'éducation des mathématiques au Canada m'intéresse activement. Après tout, l'enseignement des mathématiques au Canada compte selon moi. Sachant ceci, imaginez le sentiment d'horreur ressenti lorsque j'ai réalisé récemment que peu importe où je posais mes yeux durant cette pandémie de COVID-19, je ne faisais que constater qu'on traitait le système métrique que de façon désinvolte. Comme je l'explique dans cet article, la signalétique concernant la distanciation sociale requise en temps de COVID-19 ici au Canada se montre indifférente en regard du système métrique. Honte au Canada. Honte. Je tiens à rappeler que contrairement à ce que presque toute la signalisation qui se trouve autour de nous en ce moment prétend, deux mètres n'égalent pas six pieds. Et pendant que j'y suis, afin que ce soit clair, six pieds ne sont pas deux mètres. Que cela concerne les petites ou les grandes entreprises, ou encore les différents niveaux de gouvernance au Canada (c'est-à-dire les paliers municipal, provincial et fédéral), cela ne fait aucune différence, ici à la maison durant cette pandémie mondiale on représente le système métrique de façon maladroite. La seule bonne nouvelle c'est que je suis maintenant insensible à cette réalité, ce qui m'a permis de commencer à m'intéresser à d'autres questions liées à l'enseignement des mathématiques au Canada. Demeurez à l'écoute.

A quantitative binding model for the Apl protein, the dual purpose recombination-directionality factor and lysis-lysogeny regulator of bacteriophage 186.

The Apl protein of bacteriophage 186 functions both as an excisionase and as a transcriptional regulator; binding to the phage attachment site (att), and also between the major early phage promoters (pR-pL). Like other recombination directionality factors (RDFs), Apl binding sites are direct repeats spaced one DNA helix turn apart. Here, we use in vitro binding studies with purified Apl and pR-pL DNA to show that Apl binds to multiple sites with high cooperativity, bends the DNA and spreads from specific binding sites into adjacent non-specific DNA; features that are shared with other RDFs. By analysing Apl's repression of pR and pL, and the effect of operator mutants in vivo with a simple mathematical model, we were able to extract estimates of binding energies for single specific and non-specific sites and for Apl cooperativity, revealing that Apl monomers bind to DNA with low sequence specificity but with strong cooperativity between immediate neighbours. This model fit was then independently validated with in vitro data. The model we employed here is a simple but powerful tool that enabled better understanding of the balance between binding affinity and cooperativity required for RDF function. A modelling approach such as this is broadly applicable to other systems.

The health, well-being and future opportunities of young carers: a population approach.

OBJECTIVES: There is a lack of evidence on the health-related impacts of being a young carer. This article takes a population approach to young carer research specifically to investigate the prevalence of young carers and explore differences in their health, well-being and future expectations. STUDY DESIGN: This is a cross-sectional regression analysis. METHODS: Secondary analysis of a representative Scottish secondary school survey was undertaken. Pupils with caring responsibilities were identified, and their outcomes in terms of physical and mental health and postschool expectations were analysed. RESULTS: Almost one in eight (12%) surveyed reported caring for someone in the household. Young carers' physical and mental health and psychosocial outcomes were significantly poorer, and they were significantly less likely to see themselves entering further or higher education. CONCLUSION: This research suggests that Glasgow could have many more young carers than previously thought and provides clear evidence that young people's outcomes are influenced by carer status.

Pediatric parathyroid disease.

Parathyroid glands are critical for calcium and phosphate homeostasis. Parathyroid disease is relatively rare in the pediatric population, but there are some important pediatric-specific considerations and conditions. This article reviews parathyroid physiology, disorders of hyper- and hypo- function, operative management, and uniquely pediatric diagnoses such as neonatal severe hyperparathyroidism. Advances in preoperative imaging, intra-operative gland identification, and management of post-thyroidectomy hypocalcemia are also presented in detail. This article combines a review of fundamentals with recent advances in care, emphasizing pediatric-specific publications.

Antimicrobial resistance of Campylobacter isolates recovered from broilers in the Republic of Ireland in 2017 and 2018: an update.

1. Campylobacteriosis is the leading cause of human bacterial gastroenteritis. Broilers are considered the most important source of human Campylobacter infection. In the 2008 European baseline survey Ireland had a 98% prevalence of campylobacter-contaminated broiler carcases. 2. Randomly-selected Campylobacter isolates (296 C. jejuni, 54 C. coli) recovered in 2017 and 2018, from Irish broiler neck skin and caeca were tested for their resistance to tetracycline, erythromycin, gentamicin, ciprofloxacin, nalidixic acid and streptomycin. 3. Overall, 45% of the Campylobacter spp. isolates tested were resistant to at least one antimicrobial. Tetracycline resistance (38%) was most prevalent in C. jejuni, followed by ciprofloxacin and nalidixic acid resistance (29%). In C. coli, resistance to ciprofloxacin and nalidixic acid (26%) was most prevalent followed by resistance to tetracycline (13%). Gentamicin resistance was undetected and resistance to streptomycin was low for C. jejuni (1%) and C. coli (4%). All C. jejuni isolates examined were erythromycin-sensitive, while 9% of C. coli isolates were erythromycin-resistant. Three multidrug-resistant C. coli isolates were recovered. 4. While antibiotic resistance rates were somewhat similar to figures reported nationally over the past 20 years, the prevalence of tetracycline resistance in C. jejuni has increased. The persistence of substantial ciprofloxacin resistance in the Irish broiler population was noteworthy, despite fluoroquinolones having been banned for growth promotion in Europe since 2006.

A roadmap to build a phenotypic metric of ageing: insights from the Baltimore Longitudinal Study of Aging.

Over the past three decades, considerable effort has been dedicated to quantifying the pace of ageing yet identifying the most essential metrics of ageing remains challenging due to lack of comprehensive measurements and heterogeneity of the ageing processes. Most of the previously proposed metrics of ageing have been emerged from cross-sectional associations with chronological age and predictive accuracy of mortality, thus lacking a conceptual model of functional or phenotypic domains. Further, such models may be biased by selective attrition and are unable to address underlying biological constructs contributing to functional markers of age-related decline. Using longitudinal data from the Baltimore Longitudinal Study of Aging (BLSA), we propose a conceptual framework to identify metrics of ageing that may capture the hierarchical and temporal relationships between functional ageing, phenotypic ageing and biological ageing based on four hypothesized domains: body composition, energy regulation, homeostatic mechanisms and neurodegeneration/neuroplasticity. We explored the longitudinal trajectories of key variables within these phenotypes using linear mixed-effects models and more than 10 years of data. Understanding the longitudinal trajectories across these domains in the BLSA provides a reference for researchers, informs future refinement of the phenotypic ageing framework and establishes a solid foundation for future models of biological ageing.

Psychologists' perspectives on supported decision making in Ireland.

BACKGROUND: A new legal capacity act was introduced in Ireland in 2015. This study aimed to identify and critically examine key issues in the area of decision-making capacity from the perspective of psychologists working with adults with an intellectual disability. METHODS: A qualitative exploratory approach was employed, and the study was positioned in a social constructionist framework. Purposive and snowballing sampling methods were used to recruit 15 clinical psychologists working with adults with an intellectual disability. Data were collected with the use of individual semistructured interviews. Interview transcripts were analysed using a model of thematic analysis. RESULTS: Six themes were identified: (1) a presumption of capacity but a culture of incapacity, (2) supporting decision making as a process, (3) authenticity of decision making, (4) need for support and training, (5) contributions of psychology and (6) the way forward. CONCLUSIONS: Participants described that people with intellectual disabilities were often excluded from decision-making processes. They welcomed the functional approach to decision making, considered substituted decision making to be necessary within a support framework and described supporting decision making as a process. Systemic, resource and attitudinal challenges were identified.

On the Occasion of an Anniversary, Eh: Confessions of a Canadian Math Ed Editor.

As its title suggests, this commentary utilizes the 20th year of publication of the Canadian Journal of Science, Mathematics, and Technology Education as an opportunity for me, the current English language mathematics education editor, to confess. I confess to imposter syndrome and editorial naiveté. I confess to evolving from putting the pathetic in empathetic to near-total emotional desensitization. I confess to having stumbled upon the notions of form letters and desk rejections. I confess that my former French teachers would be disappointed in me. I confess to having never forgotten my first, to seeing ghosts, and to attempting to handle multiple concurrent timelines based on the geologic time scale. Lastly, most importantly, and utilizing an entirely different meaning of the word confess, I confess to giving credit where credit is due. In other words, what follows are the absolutely true confessions of a Canadian mathematics education editor.

Comme son titre l'indique, ce commentaire profite de la 20e année de publication du Canadian Journal of Science, Mathematics and Technology Education pour me donner l'occasion, en tant qu'actuel rédacteur anglophone pour l'enseignement des mathématiques, de faire des aveux. J'avoue avoir été atteint du syndrome de l'imposteur et avoir fait preuve de naïveté éditoriale. J'avoue avoir évolué d'une empathie pathétique à une désensibilisation émotionnelle quasi totale. J'avoue être tombé sur des esquisses de lettres types et des manuscrits rejetés par le pupitre. J'avoue que mes anciens professeurs de français seraient déçus de moi. J'avoue n'avoir jamais oublié ma première fois, avoir vu des fantômes et avoir tenté de gérer de multiples chronologies simultanées basées sur l'échelle de temps géologique. Enfin, le plus important, et en utilisant un sens complètement différent du mot « avouer ¼, j'avoue donner à chacun le crédit qui lui revient. Autrement dit, les lignes qui suivent présentent les aveux tout à fait vrais d'un rédacteur pour l'enseignement des mathématiques canadien.

Linoleic acid in diets of mice increases total endocannabinoid levels in bowel and liver: modification by dietary glucose.

AIM: Linoleic acid (LA) is an essential fatty acid involved in the biosynthesis of arachidonic acid and prostaglandins. LA is known to induce obesity and insulin resistance. In this study, two concentrations of LA with or without added glucose (G) were fed to mice to investigate their effects on endocannabinoid (EC) biology. MATERIALS AND METHODS: Four groups of C57BL/6 mice were provided with diets containing 1% or 8% LA with or without added G (LAG) for 8 weeks. Body weights, food intake, circulating glucose and insulin levels were measured throughout the study. Following euthanasia, plasma, bowel and hepatic ECs, monoacylglycerol lipase and fatty acid amide hydroxylase protein levels (enzymes responsible for EC degradation) and transcriptional activity of PPARα in liver were quantified. Liver was probed for evidence of insulin receptor activity perturbation. RESULTS: Increasing dietary LA from 1% to 8% significantly increased circulating, small bowel and hepatic ECs. 1%LAG fed mice had lowest feed efficiency, and only liver levels of both ECs were reduced by addition of G. Addition of G to 1% LA diets resulted in elevated monoacylglycerol lipase and fatty acid amide hydroxylase protein levels (p < 0.001 and p < 0.001, respectively) in liver due to increased transcriptional activity of PPARα (p < 0.05). The reduced EC levels with addition of G also correlated with a measure of enhanced insulin action. CONCLUSION: In conclusion, body weight of mice is influenced by the source of calorie intake. Furthermore, tissue EC/g are dependent on tissue-specific synthesis and degradation that are modulated by dietary LA and G which also influence food efficiency, and down-stream insulin signalling pathways. The findings could potentially be useful information for weight management efforts in humans.