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A cross-sectional investigation of preadolescent cardiometabolic health: Associations with fitness, physical activity, sedentary behavior, nutrition, and sleep
Get PDFBackground: Cardiometabolic disease (CMD) risk often begins early in life. Healthy lifestyle behaviors can mitigate risk, but the optimal combination of behaviors has not been determined. This cross-sectional study simultaneously examined the associations between lifestyle factors (fitness, activity behaviors, and dietary patterns) and CMD risk in preadolescent children.
Methods: 1480 New Zealand children aged 8–10 years were recruited. Participants included 316 preadolescents (50% female, age: 9.5 ± 1.1 years, BMI: 17.9 ± 3.3 kg/m²). Fitness (cardiorespiratory fitness [CRF], muscular fitness), activity behaviors (physical activity, sedentary, sleep), and dietary patterns were measured. Factor analysis was used to derive a CMD risk score from 13 variables (adiposity, peripheral and central hemodynamics, glycemic control, and blood lipids). Results: Only CRF (β = −0.45, p < 0.001) and sedentary time (β = 0.12, p = 0.019) were associated with the CMD risk score in the adjusted multivariable analysis. CRF was found to be nonlinear (VO₂ max ≤ ≈42 mL/kg/min associated with higher CMD risk score), and thus a CRF polynomial term was added, which was also associated (β = 0.19, p < 0.001) with the CMD risk score. Significant associations were not found with sleep or dietary variables. Conclusion: The findings indicate that increasing CRF and decreasing sedentary behavior may be important public health targets in preadolescent children
Comparing the above and below-ground chemical defences of three Rumex species between their native and introduced provenances
Get PDFCompared to their native range, non-native plants often experience reduced levels of herbivory in the introduced range. This may result in reduced pressure to produce chemical defences that act against herbivores. We measured the most abundant secondary metabolites found in Rumex spp., namely oxalates, phenols and tannins. To test this hypothesis, we compared native (UK) and introduced (NZ) provenances of three different Rumex species (R. obtusifolius, R. crispus and R. conglomeratus, Polygonaceae) to assess whether any significant differences existed in their levels of chemical defences in either leaves and roots. All three species have previously been shown to support a lower diversity of insect herbivores and experience less herbivory in the introduced range. We further examined leaf herbivory on plants from both provenances when grown together in a common garden experiment in New Zealand to test whether any differences in damage might be consistent with variation in the quantity of chemical defences. We found that two Rumex species (R. obtusifolius and R. crispus) showed no evidence for a reduction in chemical defences, while a third (R. conglomeratus) showed only limited evidence. The common garden experiment revealed that the leaves analysed had low levels of herbivory (∼0.5%) with no differences in damage between provenances for any of the three study species. Roots tended to have a higher concentration of tannins than shoots, but again showed no difference between the provenances. As such, the findings of this study provide no evidence for lower plant investments in chemical defences, suggesting that other factors explain the success of Rumex spp. in New Zealand
Lysis cassette-mediated exoprotein release in Yersinia entomophaga is controlled by a PhoB-like regulator
Get PDFSecretion of exoproteins is a key component of bacterial virulence, and is tightly regulated in response to environmental stimuli and host-dependent signals. The entomopathogenic bacterium Yersinia entomophaga MH96 produces a wide range of exoproteins including its main virulence factor, the 2.46 MDa insecticidal Yen-Tc toxin complex. Previously, a high-throughput transposon-based screening assay identified the region of exoprotein release (YeRER) as essential to exoprotein release in MH96. This study defines the role of the YeRER associated ambiguous holin/endolysin-based lysis cluster (ALC) and the novel RoeA regulator in the regulation and release of exoproteins in MH96. A mutation in the ambiguous lysis cassette (ALC) region abolished exoprotein release and caused cell elongation, a phenotype able to be restored through trans-complementation with an intact ALC region. Endogenous ALC did not impact cell growth of the wild type, while artificial expression of an optimized ALC caused cell lysis. Using HolA-sfGFP and Rz1-sfGFP reporters, Rz1 expression was observed in all cells while HolA expression was limited to a small proportion of cells, which increased over time. Transcriptomic assessments found expression of the genes encoding the prominent exoproteins, including the Yen-Tc, was reduced in the roeA mutant and identified a 220 ncRNA of the YeRER intergenic region that, when trans complemented in the wildtype, abolished exoprotein release. A model for Y. entomophaga mediated exoprotein regulation and release is proposed.
IMPORTANCE While theoretical models exist, there is not yet any empirical data that links ALC phage-like lysis cassettes with the release of large macro-molecular toxin complexes, such as Yen-Tc in Gram-negative bacteria. In this study, we demonstrate that the novel Y. entomophaga RoeA activates the production of exoproteins (including Yen-Tc) and the ALC at the transcriptional level. The translation of the ALC holin is confined to a subpopulation of cells that then lyse over time, indicative of a complex hierarchical regulatory network. The presence of an orthologous RoeA and a HolA like holin 59 of an eCIS Afp element in Pseudomonas chlororaphis, combined with the presented data, suggests a shared mechanism is required for the release of some large macromolecular protein assemblies, such as the Yen-Tc, and further supports classification of phage-like lysis clusters as type 10 secretion systems
How hindgut microbiota may shape sympatric speciation in an invasive phytophagous scarab
Get PDFFollowing the introduction of new host plants, rapid evolutionary changes in invasive phytophagous insects can sometimes result in sympatric speciation. The underlying processes and facilitation factors are still to be investigated in detail. The role of hindgut microbiota is one of these factors. In this paper, we examined the differences in the gut microbiota of two species of Costelytra scarabs (Coleoptera: Scarabaeidae, Melolonthinae), one non-invasive [Costelytra brunneum (Broun)] and one invasive (Costelytra giveni Coca-Abia & Romero-Samper), for which several ecotypes were analysed. In terms of bacterial assemblages, we found significant variation between the invasive and the non-invasive species. Three main groups of bacteria contributed to these differences, namely Oxalobacteracea, Rhizobiales, and Porphyromonadacea, with the last two potentially providing advantages in the exploitation of a new host plant. Among these bacteria, Porphyromonadacea were systematically present in high proportion in the gut of the invasive species C. giveni. The occurrence of these bacteria might have contributed to the initial capability of this insect to feed and benefit from newly introduced host plants. Furthermore, this study also revealed significant differences in the gut bacterial communities of four C. giveni ecotypes, supporting the hypothesis that part of the gut microbiota in this invasive phytophagous insect is likely to have been acquired horizontally from the newly exploited niche
Technical and nutritional properties of vegetable enriched pasta utilising juice and pomace from spinach, red cabbage, beetroot and carrot : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University
Get PDFVegetable pasta may deliver health benefits by increasing vegetable intake. Previous studies only applied one form of vegetable to pasta formula to investigate their effect. For example, Padalino, Costa, Del Nobile, and Conte (2019) used powdered glass wort (Salicornia europaea) to improve the nutritional value of pasta. In contrast, SIPOS et al. (2017) evaluated the nutritional value and sensory quality of pasta enriched with beetroot juice and beetroot puree. Few comparisons were found between different forms at the same addition level. Therefore, this study investigated the replacement of semolina with juice, puree, and pomace of spinach, red cabbage, beetroot and carrot. The effect of replacement on technical and nutritional value was evaluated.
The cooking loss of pasta made with spinach juice and spinach puree at 1 % substitution was the same as the control, while all other samples showed higher cooking loss. Spinach pasta was characterised by higher breaking force but lower breaking distance in the tensile test than the control, while all other pasta had a lower breaking force and breaking distance. Spinach pasta was generally firmer than the control. Red cabbage juice pasta was less firm than other forms of fortified pasta at 1 g/100 g substitution level. Spinach, red cabbage, beetroot and carrot juice are better colourants than puree or pomace as they change the colour of the pasta more dramatically at the same substitution level.
The in vitro starch digestibility test show that spinach pomace 10%, red cabbage pomace 10%, beetroot pomace 10%, carrot pomace 10%, spinach juice 1%, spinach puree 2%, and beetroot puree 4% significantly reduced the area under the curve of the in vitro starch digestion. This reduction was due to a combined effect of decreased starch content, increased dietary fibre content and inhibition of α-amylase caused by vegetable material addition. Total phenolic content (TPC) and antioxidant capacity increased significantly on raw, cooked and digested samples of vegetable-fortified pasta compared to the control. The β-carotene content of spinach and carrot pasta samples (raw, cooked, and digested) was also higher than that of the control. At the same substitution level, the juice was more efficient in improving the antioxidant capacity of resultant pasta compared to puree or pomace. Mineral contents of vegetable-fortified pasta (raw and cooked) were also higher than the control. In general, at the same lower substitution level, juice and puree-enriched pasta samples generally exhibited better technical quality than pomace-enriched ones. The study exhibits that incorporating vegetable juice or puree to produce pasta results in a superior nutritional profile with a slight compromise of technical quality
Connecting through research: A collaborative autoethnography of a positive culture in an inter-institutional research group
Get PDFThe LUCARA (Lincoln University, University of Canterbury, and Ara Te Pūkenga) group is a thriving research group based in Ōtautahi Christchurch, New Zealand. The group consists of nine academics in sport and exercise science, health, and nutrition at the three tertiary institutions. The majority of the group members had previously been involved in collaborative research for over 10 years. Initially, the relationships during this time were largely transactional, for example, editorial feedback, funding support, data collection, and statistical support. However, in the last two-and-half years, the group has matured, and relationships have deepened with weekly meetings, connections, and partnerships, which has produced a large increase in the number of collaborations between researchers, sharing of resources, and hence increased research outputs. This narrative explores the organic researcher-led growth in the group, and uses the theme of connections to gain an understanding of how this culture has blossomed over a relatively short time in a sport and allied health research setting
Modelling wine grapevines for autonomous robotic cane pruning
No full textAotearoa (New Zealand) has a strong and growing winegrape industry struggling to access workers to complete skilled, seasonal tasks such as pruning. Maintaining high-producing vines requires training agricultural workers that can make quality cane pruning decisions, which can be difficult when workers are not readily available. A novel vision system for an autonomous cane pruning robot is presented that can assess a vine to make quality pruning decisions like an expert. The vision system is designed to generate an accurate digital 3D model of a vine with skeletonised cane structures to estimate key pruning metrics for each cane. The presented approach has been extensively evaluated in a real-world vineyard as a commercial platform would be expected to operate. The system is demonstrated to perform consistently at extracting dimensionally accurate digital models of the vines. Detailed evaluation of the digital models shows that 51.45% of the canes were modelled entirely, with a further 35.51% only missing a single internode connection. The quantified results demonstrate that the robotic platform can generate dimensionally accurate metrics of the canes for future decision-making and automation of pruning
The effect of farmyard stress on meat quality: A model for predictive biomarkers of meat pH
No full textBackground/Objectivs: High pH meat is frequently associated with poor shelf-life and eating quality, and pH is a commonly used marker for meat quality. Early detection of high pH lamb is desirable and can improve meat quality control. Due to the variability in the occurrence of high pH at meat processing plants in New Zealand, there is a need for reproducible models that allow the study of abnormal pH in meat. We devised a pilot trial using standardised farmyard stress to produce high pH meat.
Method: This experiment compared lambs exposed to some of the normal pre-slaughter stress factors within a New Zealand pastoral system with a control group with minimal pre-slaughter stress. It used two groups of 10 lambs, held in the pasture paddock next to the abattoir. The 10 “low stress” animals were kept quietly in pens prior to slaughter while the second group of 10 animals were exercised by moving with a dog for 5-10 minutes every hour for 4 hours prior to slaughter (“moderate exercise stress”). Rapid metabolomics (rapid evaporative ionisation mass spectrometry, REIMS) analyses were carried out on the immediate post-slaughter samples. The carcasses were aged and meat quality measurements were taken at different post mortem time points: pH (at 1.5 h, 24 h), colour (at 4 days), cooking loss and shear force (at 7/8 days).
Results: The pH declined significantly over the 24 h post-slaughter in all muscles. At 1.5 h post-mortem, there was no significant difference in the average pH of muscles among non-exercised (pH 6.650, N=100) and exercised groups (pH 6.683, N=99). When the pH of two different fibre types was compared as an early sign of pH response to pre-slaughter exercise stress, the slow/oxidative muscle types had significantly higher pH than the same muscle types from non-exercised group (p=0.011). This was not seen in fast/glycolytic fibre muscles. At 24 h post-mortem muscles, the pH of the muscles from exercised group (N=99, pH 6.14) was significantly higher in comparison to the muscles from non-exercised (N=100, pH 5.85, p=0.000). Exercise stress also resulted in differences in other meat quality measurements. Colour, cooking loss and shear force of some muscles were changed after exercise stress. REIMS analysis found clear metabolite-based differences between muscles from exercised and control sheep, and between muscles.
Conclusion: We have developed a model for generating high pH lamb based on farmyard pre-slaughter stress. This resulted in changes to several important meat quality markers. Samples from this trial have been used for fingerprinting mass spectrometry to identify new potential predictive markers of high ultimate pH. This simple farmyard stress model is a useful tool for research on high pH meat under controlled yet realistic conditions, and follow up validation trials has confirmed the reproducibility of this model. In future, biomarkers of high pH in the meat could be used for enhancing animal welfare and confirm the relationship between minimising pre-slaughter stress and improving the consistency of meat quality
The commercial application of insect protein in existing human foods: A product audit based on online resources
No full textThe growing global population and expanding pet food market have heightened the demand for protein. Escalating costs and environmental concerns in traditional animal protein production have prompted a search for sustainable alternatives, where insect-based protein stands out due to its high nutritional content and eco-friendly credentials. To explore the commercial application of insect protein in existing human and pet foods, this study aims to profile and compare ultra-processed food products containing insect protein (insect protein-enriched foods) with equivalent traditional products. A global product audit was conducted in August 2023 drawing from both English-language and Chinese-language online retail portals. Nutritional content, ingredients list, and label information have been collected for insect protein-enriched foods for humans comprising flour, pasta, chips and energy bar; and for pets, primarily for dogs and cats. This data was statistically summarised and compared. Our research contributes to bridging existing knowledge gaps and providing a foundation for future research through a comprehensive audit of insect protein-enriched food products, offering potential benefits across academic, manufacturing, marketing, and policy-making domains
Assessment of the recovery and photosynthetic efficiency of Breviolum psygmophilum and Effrenium voratum (Symbiodiniaceae) following cryopreservation
No full textMany strains of Symbiodiniaceae have been isolated and their genetics, taxonomy, and metabolite production studied. Maintaining these cultures requires careful and regular sub-culturing that is costly with a high risk of species contamination or loss. Cryopreservation is a viable alternative for their long-term storage; however, there is uncertainty as to whether cryopreservation impacts the photosynthetic performance of Symbiodiniaceae. We investigated the growth rates and photosynthetic efficiency of two species, Breviolum psygmophilum and Effrenium voratum before and after cryopreservation. Rapid light curves (RLCs) produced using Pulse Amplitude Modulated (PAM) fluorometry were used to generate detailed information on the characteristics of photosystem II (PSII). The maximum electron transport rate (ETRmax) and the quantum yield (Fv/Fm) of the control (non-cryopreserved) and cryopreserved culture isolates were assessed across the growth cycle. The non-cryopreserved isolate of B. psygmophilum had a higher quantum yield than the cryopreserved isolate from day 12 to day 24, whereas there were no differences from day 28 to the late stationary phase. There were no significant differences in ETRmax. No significant differences were observed in quantum yield or ETRmax between the control and cryopreserved E. voratum isolates. The ability of cryopreserved strains to recover and regain their photosynthetic efficiency after freezing demonstrates the utility of this method for the long-term storage of these and other Symbiodiniaceae species