Welcome to Massey Research Online
Massey Research Online is an open access digital archive of the research and scholarship of Massey University and is jointly managed by the University Library and Information Technology Services.
Massey Research Online contains research theses and research outputs including published work by Massey University students and academic staff as well as peer-reviewed material not published elsewhere. In the case of previously published research outputs all requirements of copyright owners are observed.
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Sustainable Careers within Greening Economies
(Australian Council for Educational Research for SAGE Publications, 2024-10-08) Hopner V; Carr S; Wloch J
Sustainable Livelihoods are more adaptable than precarious jobs, for career development through Decent Work. An essential element for Career Sustainability is Climate action, that includes Just Transitions from carbon-intensive to carbon-neutral or regenerative work. This paper analyses a municipal transition from coal-mining to a more carbon-neutral, city economy, which has foregrounded just transition for miners, and improved the wider ecosystem. The Polish city of Katowice in Poland illustrates how work and career structures, in this case municipal, can work for people in everyday life and their future careers. The case may also serve as a lighthouse project for future just transitions, as part of sustainable career development, by greening economies and supporting access to decent work for all.
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Gut-Brain Axis in the Early Postnatal Years of Life: A Developmental Perspective
(Frontiers Media S.A., 2020-08-05) Jena A; Montoya CA; Mullaney JA; Dilger RN; Young W; McNabb WC; Roy NC; Cammarota M
Emerging evidence suggests that alterations in the development of the gastrointestinal (GI) tract during the early postnatal period can influence brain development and vice-versa. It is increasingly recognized that communication between the GI tract and brain is mainly driven by neural, endocrine, immune, and metabolic mediators, collectively called the gut-brain axis (GBA). Changes in the GBA mediators occur in response to the developmental changes in the body during this period. This review provides an overview of major developmental events in the GI tract and brain in the early postnatal period and their parallel developmental trajectories under physiological conditions. Current knowledge of GBA mediators in context to brain function and behavioral outcomes and their synthesis and metabolism (site, timing, etc.) is discussed. This review also presents hypotheses on the role of the GBA mediators in response to the parallel development of the GI tract and brain in infants.
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Impact of a High Protein Intake on the Plasma Metabolome in Elderly Males: 10 Week Randomized Dietary Intervention
(Frontiers Media S.A., 2019-12-06) Durainayagam B; Mitchell CJ; Milan AM; Zeng N; Sharma P; Mitchell SM; Ramzan F; Knowles SO; Sjödin A; Wagner K-H; Roy NC; Fraser K; Cameron-Smith D
High protein diets may improve the maintenance of skeletal muscle mass in the elderly, although it remains less clear what broader impact such diets have on whole body metabolic regulation in the elderly. Non-targeted polar metabolomics analysis using HILIC HPLC-MS was used to profile the circulating plasma metabolome of elderly men (n = 31; 74.7 ± 4.0 years) who were randomized to consume for 10 weeks a diet designed to achieve either protein (RDA; 0.8·g-1·kg-1) or that doubled this recommend intake (2RDA; 1.6.g.kg-1). A limited number of plasma metabolites (n = 24) were significantly differentially regulated by the diet. These included markers of protein anabolism, which increased by the 2RDA diet, including; urea, creatine, and glutarylcarnitine. Whilst in response to the RDA diet; glutamine, glutamic acid, and proline were increased, relative to the 2RDA diet (p < 0.05). Metaboanalyst identified six major metabolic pathways to be influenced by the quantity of protein intake, most notably the arginine and proline pathways. Doubling of the recommended protein intake in older males over 10 weeks exerted only a limited impact on circulating metabolites, as determined by LC-MS. This metabolomic response was almost entirely due to increased circulating abundances of metabolites potentially indicative of altered protein anabolism, without evidence of impact on pathways for metabolic health.
Trial Registration: This trial was registered on 3rd March 2016 at the Australia New Zealand Clinical Trial Registry (www.anzctr.org.au) at ACTRN 12616000310460.
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Concentrations of Fecal Bile Acids in Participants with Functional Gut Disorders and Healthy Controls
(MDPI (Basel, Switzerland), 2021-09-09) James SC; Fraser K; Young W; Heenan PE; Gearry RB; Keenan JI; Talley NJ; Joyce SA; McNabb WC; Roy NC; Apidianakis Y; Agapiou A
Bile acids are metabolites involved in nutrient absorption and signaling with levels influenced by dietary intake, metabolic processes, and the gut microbiome. We aimed to quantify 23 bile acids in fecal samples to ascertain if concentrations differed between healthy participants and those with functional gut disorders. Fecal bile acids were measured using liquid chromatography-mass spectrometry (LC-MS) in the COMFORT (The Christchurch IBS cohort to investigate mechanisms for gut relief and improved transit) cohort of 250 participants with Rome IV IBS (IBS-constipation (C), IBS-diarrhea (D), IBS-mixed (M)), functional gut disorders (functional constipation (FC), functional diarrhea (FD)) and healthy controls (FC n = 35, FD n = 13, IBS-C n = 24, IBS-D n = 52, IBS-M n = 29, and control n = 97). Dietary information was recorded to ascertain three-day dietary intake before fecal samples were collected. Fecal bile acid concentrations, predominantly primary bile acids, were significantly different between all functional gut disorder participants and healthy controls (CDCA p = 0.011, CA p = 0.003) and between constipation (FC + IBS-C) and diarrhea (FD + IBS-D) groups (CDCA p = 0.001, CA p = 0.0002). Comparison of bile acids between all functional groups showed four metabolites were significantly different, although analysis of combined groups (FC + IBS-C vs. FD + IBS-D) showed that 10 metabolites were significantly different. The bile acid profiles of FD individuals were similar to those with IBS-D, and likewise, those with FC were similar to IBS-C. Individuals with a diarrhea phenotype (FD + IBS-D) had higher concentrations of bile acids compared to those with constipation (FC + IBS-C). Bile acid metabolites distinguish between individuals with functional gut disorders and healthy controls but are similar in constipation (or diarrhea) whether classified as IBS or not.
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The kinetics of amino acid disappearance in the small intestine is related to the extent of amino acids absorbed in growing pigs
(Cambridge University Press on behalf of The Nutrition Society, 2024-03-14) Montoya CA; van Bemmel M; Kreutz K; Hodgkinson SM; Stroebinger N; Moughan PJ
This study evaluated the importance of a correction for amino acids (AA) released into the hindgut on a measure of AA absorption kinetics and tested whether AA absorption kinetics are related to the extent of AA absorption using the growing pig as a model for humans. Thirty-six nine-week-old pigs (22·3 kg) received a diet containing whey protein as the sole protein source for 8 d. Pigs received their last meal containing the indigestible marker titanium dioxide before being euthanised at 1, 2, 3, 4, 6 and 12 h post-feeding. The entire content of each gastrointestinal tract (GIT) region was collected to determine AA released into the hindgut, and the kinetics and extent of AA absorption (uncorrected and corrected for AA entering the hindgut). Amounts of AA released into the hindgut increased over time (e.g. 33 and 180 mg of Glu for 4 and 6 h post-feeding). The corrected apparent amount of each AA absorbed from the GIT lumen after 4 h post-feeding was generally lower (P ≤ 0·05) than the uncorrected counterpart. Differences in both the kinetics and extent of AA absorption were observed across AA. For example, the time to reach half of the apparent AA absorption (T50) was 1·5 and 3·4 h for Met and Arg, respectively, whereas their extent of apparent absorption was 93 and 73 %. Negative correlations between parameters related to kinetics and the extent of apparent absorption were observed (e.g. for T50 r = -0·81; P < 0·001). The kinetics of AA absorption is related to the extent of AA absorption.