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Immune-Boosting Functional Foods: A Potential Remedy for Chinese Consumers Living Under Polluted Air
No full textThe deterioration of air quality in China has resulted in many people looking for technological approaches or medical remedies to counteract the impact that air pollution is perceived to be having on their health and wellbeing. As the importance of diet on immune health is becoming increasingly well recognised, there is increasing interest in the development of food products designed to help the immune system recover from the impact of air pollution. A narrative literature review was undertaken to elucidate Chinese consumers’ acceptance and market potential of functional food products designed to help the immune system recover from the impact of air pollution. Topics reviewed included, the functional food market in China, scientific findings on how functional foods / ingredients can enhance immune health, the actions that Chinese consumers take to limit exposure to and combat the effects of pollution and their perceptions of immune-boosting functional foods. Consumers’ attitude towards functional foods including those designed to enhance the immune system were mainly positive, with scientific validation being important in determining the credibility of a product. This was despite the fact that the effectiveness of the functional food products currently in the market which purported to be remedies for pollution-driven impacts on the lung did not appear to be supported by scientific evidence. Numerous studies have reported functional foods could provide a wide range of benefits to immune health, including helping pollution-driven immune issues. This review shows that there would appear to be market demand for effective and scientifically-proven functional food products that help Chinese consumers’ immune system recover from the impact of air pollutio
An investigation into dysfunctional feed-forward inhibition within the cortico-thalamocortical network on absence seizure generation using DREADD technology
No full textChildhood absence epilepsy (CAE) is one of the most prevalent paediatric epilepsies, accounting for between 10-17% of all diagnosed cases of epilepsies seen in school-aged children. Absence seizures are characterized by behavioural arrest/loss of awareness and electrographic signature of spike-wave discharges (SWDs) measuring 2.5-4 Hz on an electroencephalogram (EEG). These brief episodes of impaired consciousness can occur hundreds of times a day and might increase the chance of physical injury when undertaking activities like swimming and cycling. Current treatment options are not sufficient and up to 30% of patients are pharmaco-resistant. ~60% of children with CAE have severe neuropsychiatric comorbid conditions including attention deficits, mood disorders, impairments in memory and cognition. Ethosuximide (ETX), an anti-absence epileptic drug which was first introduced almost six decades ago remains the first choice for initial monotherapy for the treatment of CAE. Large-scale clinical trials suggested that efficacy of ethosuximide is considerably lower than previous findings. Thus, safe, effective and patient specific treatment approach is imperative. For this, it is crucial first to understand the precise cellular and molecular mechanisms of absence seizures which may enable the development of novel therapeutic targets and discovery of new anti-epileptic drugs (AEDs).
EEG and functional imaging evidence suggest that absence seizures are likely due to aberrant activity within the cortico-thalamocortical (CTC) network. Studies involving the genetic rodent models have shown that the cortex is the driving source for the origin of SWDs but is not capable of maintaining discharges on its own, nor is the thalamus. General consensus is that, within the CTC network, a cortical focus initiates rhythmic epileptic discharges, however, once the rhythmic oscillations are established, both the cortex and thalamus form an integrated network. Rhythmic absence-SWDs are sustained via the cortex and thalamus driving each other. Within the CTC network, feed-forward inhibition (FFI) is essential to prevent runaway excitation. FFI is mediated by fast spiking parvalbumin expressing (PV+) inhibitory interneurons in the somatosensory cortex (SScortex) and the reticular thalamic nucleus (RTN). Studies conducted in well-established stargazer mouse model of absence epilepsy with a genetic deficit in stargazin i.e. TARP [a transmembrane α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor regulatory protein] have shown reduced expression of GluA4-AMPARs at excitatory synapses in feed-forward inhibitory (PV+) interneurons in the SScortex and RTN thalamus of the CTC network. However, the extent of this deficit in AMPARs expression impacting FFI and possibly contributing towards generation of absence-SWDs is not established via functional studies.
Hence, this thesis was aimed at investigating the impact of dysfunctional feed-forward inhibitory PV+ interneurons within CTC network on absence seizure generation and behaviour. For this purpose, inhibitory and excitatory Designer Receptors Exclusively Activated by Designer Drug (DREADD) approach was utilized to silence/excite feed-forward inhibitory PV+ interneurons within the CTC network. DREADD mediated regional silencing of PV+ interneurons within the CTC network generated ETX-sensitive absence-like SWDs. Activating PV+ interneurons either prevented or suppressed pentylenetetrazole (PTZ)-induced absence-SWDs. Finally, impact of impaired FFI in γ-aminobutyric acid (GABA) levels by affecting its synthesizing enzymes (GADs) and transporter proteins (GATs) in stargazer animal model of absence epilepsy and CNO treated inhibitory Gi-DREADD animals was determined. Results indicate that upregulation of GAD65 in the SScortex of epileptic stargazers may be a consequence of absence seizures or this may have contribution in absence seizure generation.
The work presented in this thesis provide an electrophysiological insight into the possible mechanism underlying the absence seizure generation. This work provides convincing evidence that dysfunctional feed-forward inhibitory PV+ interneurons within the CTC network is likely to be involved in altered excitation/inhibition balance resulting SWDs as activating these interneurons dramatically protected animals from PTZ induced absence seizures. The clinical relevance of this study is that it potentially uncovers the possibility of focally targeting PV+ interneurons within the CTC network to control absence seizures in human patients
Expanding the utility of the zinc and cadmium stable isotope micronutrient proxies, and reconstructing palaeo-productivity through the last deglaciation
No full textThe oceanic biogeochemical cycling of trace metal micronutrients is being progressively developed to assess the efficiency of the ocean’s ‘biological pump’, atmospheric carbon dioxide (CO2) sequestration, and ocean-atmosphere climate cycling due to their biological importance to phytoplankton growth and marine primary production. Technological advancements have facilitated investigations into the micronutrient biogeochemical cycling in the modern ocean using seawater samples, and in the past oceans using mineral archives that retain a seawater component at the time of formation. These developments have recently enabled the use of micronutrient stable isotope systems to reconstruct variations in the coupling between the ocean’s ‘biological pump’ and carbon-climate cycling throughout Earth’s history, with enhanced resolving power compared with concentration analyses alone.
In this thesis, the utility and accuracy of the zinc (Zn) and cadmium (Cd) isotope micronutrient systems is vastly expanded for accurate reconstructions of past seawater and marine primary productivity. To achieve this, four primary objectives were targeted. First, a scarcely utilised ‘double-spike’ design was used to obtain enhanced analytical resolution, required to accurately document subtle but distinct isotope fractionation that is typical of the Zn isotope system in seawater. To this end, up to a factor of four improvement in measurement precision is routinely attained by implementing a 70Zn-67Zn double spike design, compared with traditionally used double spikes, while accuracy is maintained across a range of Zn load sizes and matrix types. New and refined Zn isotope values for a suite of certified reference materials and standards are provided for use across multiple emerging disciplines, and the analytical improvements could be essential for documenting previously unresolvable biogeochemical processes.
Second, the utility of commonly used carbonate chemical cleaning protocols, and the effects of partial carbonate dissolution on recent Holocene (<11,000 year old) surface carbonate sediments and an ancient Mesozoic (~94 million year old) carbonate sediment, was interrogated for Zn and Cd isotope analysis. This study demonstrates that accuracy is improved by using carbonate chemical cleaning methods that selectively remove contaminating secondary iron-manganese (Fe-Mn) (oxyhydr)oxide phases. However, the ‘reductive step’ required to achieve this could induce anomalous zinc isotope fractionation and must be carefully monitored. Natural and laboratory-controlled partial carbonate dissolution is also shown to cause Zn and Cd isotope fractionation. This study provides an evidence-based approach to selecting the methodological protocols that can be used to obtain accurate Zn and Cd isotope analysis in carbonates. Furthermore, this study highlights that partial carbonate dissolution must be accounted for, or avoided, in Zn and Cd isotope palaeo-productivity reconstructions across all time periods.
Third, a suite of seven Holocene surface carbonate sediments retrieved from the New Zealand and southeast African continental margins were used to construct, for the first time, full water column calibrations between the Zn and Cd isotope composition of carbonates, and modern seawater. In particular, an in-depth study of the Zn and Cd isotope systematics of individual species of foraminifera, and the zooplankton and phytoplankton fractions, as well as the typically used bulk sediment fraction, was conducted. These sediments were obtained from either side of the subtropical frontal zone in the Southern Ocean that provides a natural laboratory to investigate the systematics of Zn and Cd isotopes in past seawater across a wide range of physical and chemical conditions. Biogenic carbonates record a Cd isotope signature that is systematically offset from seawater towards lighter isotopic compositions and is largely insensitive to Cd concentration. Upon correction for these isotope effects, the seawater Cd isotope signature can be accurately reconstructed. The Cd isotope composition of secondary Fe-Mn (oxyhydr)oxide coatings precipitated on the primary foraminifera carbonate surface is unfractionated relative to the seawater, providing an estimate for the Cd isotope composition of the bottom water overlying each site. Carbonates record a systematically heavy Zn isotope composition relative to seawater and require correction for the concentration dependence of isotope fractionation associated with adsorption. Accurate correction for these Zn isotope effects allow the seawater signature to be reconstructed. Furthermore, particulate organic matter is shown to represent a sink for light Zn and Cd isotopes. The magnitude of this isotopically light sink is capable of balancing the Zn and Cd sources to the oceans from riverine and atmospheric inputs.
Finally, the novel Zn isotope system was applied, for the first time, as a micronutrient palaeo-productivity tool in down-core carbonate sediment samples from the southeast African continental margin, a region that is highly sensitive to changes in southern and northern hemisphere climate change. The zinc/calcium and Zn isotope compositions of carbonates are used to demonstrate that the southeast Indian Ocean was depleted in Zn during the Last Deglaciation that occurred from ~21 to ~11 thousand years ago (ka), but variations in the regional hydroclimate during the following Holocene interval increased the supply of nutrients to the mixed layer increasing primary production. The position of the subtropical front, south of Africa, is shown to have shifted southwards since the Last Glacial Maximum at ~21 ka, which could have accelerated northern hemisphere deglaciation and strengthened Atlantic Meridional Overturning Circulation. Finally, periods of micronutrient depletion and repletion at the northern margin of the Southern Ocean correspond to abrupt ocean-climate reorganisations during the Last Deglaciation.
The enhanced resolving power and high sensitivity of the Zn and Cd isotope micronutrient systems, compared with elemental concentrations alone, will make these palaeo-productivity proxies indispensable for constraining carbon and climate cycling mechanisms in Earth’s past that can be used to better predict possible future climate scenarios
Parental attitudes toward weaning practices and weaning foods for health in Malaysia
No full textThe purpose of this paper is to gain insight on parental attitudes towards weaning practices and weaning foods for health in Malaysia using Q-methodology. The study population was parents that had a child aged three years or less. A total of 47 parents were recruited to partake in a one-on-one activity which involved sorting 69 statements about weaning practices and weaning food products into a grid that was normally distributed ranging from “strongly disagree” to “strongly agree”. Sorting was immediately followed by a short interview to understand the reasons behind the placement of particular statements. Data analysis identified three statistically distinct participant attitudes towards weaning practices and foods for health that were then interpreted using the rich qualitative data from the post-sort interviews. The attitudes identified were “All Homemade and Natural”, “Commercial Convenience and Trust” and “Balance and Variety”. This study identified the dominant sets of attitudes held by Malaysian parents towards weaning practices and weaning foods for health using Q-methodology. To authors’ knowledge, this is the first paper focusing on weaning foods for health, specifically on functional weaning food. This new understanding of shared attitudes will allow product developers, marketers and health communicators to more effectively design their products and their marketing mix to ensure that these messages resonate well with the target audience who want to provide the best weaning foods possible for their children
Gauging attitudes and behaviours: Meat consumption and potential reduction
No full textThe present study focused on adding to the understanding of meat consumption and potential drivers for its reduction in New Zealand. Using the Theory of Planned Behaviour (TPB) and the recently developed Meat-Attachment Questionnaire (MAQ), this study investigated New Zealand consumers' attitudes, motivations and behaviours in regards to meat consumption. Results derive from a questionnaire sent across New Zealand in March 2017, in which 841 responses were obtained from representative consumer panels. Consumer awareness of the severity of meat's environmental impacts was found to be quite low in comparison to other sustainable food behaviours. Motivations for reduction seem to shift across consumer groups, with different considerations rising and falling in importance depending on current meat consumption habits. Among the TPB components, only attitudes were found to accurately and consistently predict willingness and intentions to reduce personal meat intake, while both attitudes and subjective norms predicted agreement with proposed structural measures that would promote meat reduction and/or plant-based food consumption. In addition, the MAQ was found to provide explanatory power above and beyond that of the TPB components alone and this research supports its use as a tool to further understand meat consumption and potential motivations for reduction. The authors believe these results could be useful for governments or organizations wishing to implement meat reduction strategies, as well as providing a stepping stone for further research inquiry into motivations behind meat consumption and its potential reduction
Consumer acceptance of insects and ideal product attributes
No full textInsects can be sustainably produced and are nutrient rich. However, adoption of insects in western culture, including New Zealand (NZ) is slow. The purpose of this paper is to explore consumer attitudes, drivers and barriers towards entomophagy and uncover consumer expectations surrounding what their ideal insect product attributes are. In total, 32 participants took part in three product design workshops. This involved two sections. First, focus groups discussion took place surrounding consumer acceptance. Second, following adapted consumer idealised design, groups of three or four designed their ideal liquid and solid product incorporating extracted insect protein. Designs included the ideal product, place, price and promotional attributes. Participants were both disgusted and intrigued about entomophagy, with common barriers including; culture, food neophobia, disgust sensitivity, lack of necessity and knowledge. Motivational drivers were novelty, health, sustainability and/or nutrition. Most of the liquid and solid food products were designed as a premium priced sweet snack, drink or breakfast option, as opposed to a meat substitute. The convenience, health and sustainability benefits of certain products were promoted towards health and fitness oriented consumers. Whereas, other designs promoted the novelty of insects to kids or the general population, in order to introduce the idea of entomophagy to consumers. The study is the first attempt at uncovering what insect products NZ consumers are accepting of; therefore, contributing to both limited research and product development opportunities for industry
Clarifying the waters: A critical analysis of turbidity and its role in environmental monitoring in New Zealand
No full textTurbidity is widely-used as a water quality indicator to infer the mass of suspended sediment (SS) transported through riverine systems, and is inexpensive, readily available, and can be easily deployed to record continuous measurements. However, using turbidity as a surrogate for SS concentration (SSC) is frequently confounded by the composition of riverine suspended material, and the particle size and shape of sediments. Presented as a series of research papers, this thesis provides a distinctly Southern Hemisphere perspective of sediment, organic matter, organic carbon, and turbidity across southern New Zealand, and offers a critical reflection on the role of turbidity in environment monitoring. The suspended material of southern New Zealand rivers under base flow was mostly comprised of inorganic suspended material, although the total composition also includes variable amounts of organic material (<10%, and up to 50 – 80%). The proportion of organic to inorganic particulate material in southern New Zealand is significant under certain land covers, and contributes a significant proportion of particulate organic carbon flux to the Southern Oceans (0.04 – 2.7 t km-1 a-1). In addition, different catchment morphologies and lithologies have a propensity to discharge different particle size distributions of inorganic sediment. These differences in particle sizes are most likely a function of underlying lithology from in channel attrition. This thesis has also identified that specific turbidity (turbidity normalised to mass concentration of particulates) is a potentially effective metric to indicate a ‘non-standard’ light attenuation response (that is, greater turbidity per mass of SS). Specific turbidity is shown through both in-field measurements and laboratory experiments to be affected by organic composition (particulate and dissolved) and the particle size distribution. Multiple regression analysis of catchment characteristics show that suspended particulate material composition and particle size are linked to discharge and flow behaviour, landcover, and lithology. The application of these findings is applied to monitoring SSC with turbidity across New Zealand by examining the specific turbidity for 77-monitoring stations. It is evident that organic composition and particle size have a notable effect on SS-turbidity ratings across New Zealand, which has limitations for the comparability, and relevance of SS data derived from turbidity when used as a regulatory tool. This thesis shows that although turbidity is pragmatic, its use in SS monitoring is problematic
The social value of rescuing food, nourishing communities
No full textThe purpose of this paper is to explore the social value food rescue enterprises can create for both their stakeholders and the wider community “in the meantime” whilst longer term solutions to the problems of insecurity and waste are sought. FoodShare, a New Zealand urban-based social enterprise specialising in food redistribution, served as a case study for this research. Semi-structured interviews (n ¼ 13) were conducted with FoodShare staff and key stakeholder groups (food donors, financial donors, recipient agencies and volunteers). In addition, an anonymous online survey (n ¼ 40) was completed by the wider organisational volunteer network. The interview guides were structured around a new social value evaluation tool, Social Return on Investment, which is increasingly used to demonstrate the impact of such programmes. Deductive methods were used to code the resulting transcripts to identify key outcomes experienced by FoodShare’s stakeholders. The outcomes of FoodShare’s work differed for the various stakeholders. For food donors, outcomes included “more involved relationships with community”, and “improved perceptions of corporate social responsibility”. Identified key outcomes for the financial donors included “key promotional opportunity” and “do something good”. For recipient agencies, important outcomes were “greater volume of food” and “increased reach”. Volunteers reported “meeting new people”, “a sense of accomplishment in helping others” and “learning new skills”. There were also a number of nutritional and environmental outcomes for the wider community. Given the dearth of evidence on the societal value that is created in redistributing unsold food to people in need, this novel perspective makes a significant contribution to the literature in this area
An Exploratory Qualitative Exploration of the Personal Values Underpinning Taiwanese and Malaysians’ Wine Consumption Behaviors
No full textAugmented buying power of East Asian consumers has resulted in increased interest in these markets. Wine is a particularly promising sector to target as the number of East Asians choosing to drink wine rises. In order to serve these markets, companies must understand factors influencing consumers’ choices. The objective of this research was to understand how Taiwanese and Malaysian consumers’ personal values influenced their consumption decisions about wine. The means–end chain framework and associated semi-structured interview technique, value laddering, was used to elicit consumers’ preferred product attributes, the consequences of these attributes and the values that underpin these consequences. Data collection involved intercepting foreign travelers from Malaysia and Taiwan in New Zealand (20 Taiwanese and 20 Malaysian) to partake in a wine choice interview. The resulting findings are exploratory in nature. Analysis revealed the most preferred wine attributes for Taiwanese were “Price” and “Sensory Aspects”—that these attributes were linked to consequences “Financial Considerations” and “Satisfy Senses”—which in turn were linked to personal values “Self Direction” and “Achievement”. For the Malaysian participants, the attribute “Sensory Aspects” of wine was most important, as was the value “Hedonism”. This study adds to literature related to beverage consumption decision making by exploring cultural aspects. It also offers suggestions for practitioners interested in targeting these consumers
Formulation and evaluation of a stable penethamate hydriodide intramuscular injection for treatment of bovine mastitis
No full textPurpose: The aim of this thesis was to investigate the stability of penethamate (PNT), an ester prodrug of benzylpenicillin (BP), used intramuscularly (i.m.) in the treatment of bovine mastitis. The specific objectives were to understand the chemical stability of PNT in aqueous and oily vehicles; to develop some understanding of the effect of absorption rate from the i.m. site on milk levels of BP; to formulate a stable ready-to-use (RTU) product and to test this product in a pilot study in the target species (cow).
Methods: A reversed phase HPLC assay was developed to study the degradation kinetics of PNT in aqueous vehicles. Several formulation approaches such as cosolvents, cyclodextrins, common ion and oily vehicles to enhance the
chemical stability of PNT were assessed. A simulation model was constructed for the prediction of absorption rate from i.m. injection site and concentration of BP, the hydrolytic product of PNT, in milk. A pilot animal study in cows was conducted to compare milk levels of BP after i.m. injection of a stable oily formulation of PNT with a marketed aqueous reconstituted suspension formulation.
Results: A reversed phase HPLC assay for simultaneous determination of PNT and its hydrolytic product BP using an isocratic system with photo diode array detection was developed and validated. The assay was linear over the concentration range 1-100 μg ml-1 for both analytes (r > 0.99) with satisfactory inter-day and intraday
precision (RSD ≤ l %) and accuracy (98-99%) for PNT.
The degradation of PNT in aqueous solutions followed pseudo-first-order kinetics over the pH range 2 - 9.3 with a V- shaped pH-rate profile with a sigmoid portion in the pH range 7.5 - 9.3 corresponding to the pKa (8.4) of PNT. The
minimum degradation rate of PNT was at pH 4.5 (half-life (t1/2) = 44 h at 30 °C). The impact of buffer concentration and ionic strength on PNT stability was small but at pH 6 the type of buffer salt had some influence with solutions in acetate being about twice as stable as those in phosphate. The Arrhenius activation energies determined at pH 3.01, 6.01 and 8.04 were 62.1, 74.1 and 98.8 kJ mol-1 respectively.
In aqueous solutions, propylene glycol (PG) increased the t1/2 of PNT from 1.8 days to 4.3 days at 30 °C, whereas hydroxypropyl- ß-cyclodextrin (HP-ß-CD) and ß-CD did not influence the t1/2 and iodide (I-) resulted in a decrease in t½ from 1.8 days to 1.1 days. The estimated shelf-life (t90) of PNT in solution of about 0.3 days (5% PG) and 0.7 days (60% PG) increased to 15 days (5% PG) and 11 days (60% PG) in a 50% PNT suspension. With increasing concentration of HP-ß-CD, the solubility of PNT increased linearly and resulted in a decrease in the estimated t90 of aqueous suspensions. The decrease in solubility of PNT due to the common ion effect resulted in an increase in the t90 (26 days) in aqueous suspension.
PNT stability (% drug remaining) in oily suspensions after 105 days was in the order LP (light liquid paraffin) (96.2%) > MIG (miglyol 812) (95.4%) > EO (ethyl oleate) (94.1%) > SO (sunflower oil) (86.4%). PNT degradation was rapid in oily solutions of LP, MIG, EO and SO and less than 10 % remained after 7-15 days.
The simulation model provided insights into the absorption rate of PNT from the i.m. injection site. Sensitivity analysis suggested that absorption rate constants (ka), clearance from plasma to milk (PA) and volume of distribution (Vd) are critical parameters for predicting concentrations of BP in milk. The developed oily suspension formulation of PNT in EO with 0.15 % Polysorbate 80 showed good physical and chemical stability. A pilot animal study in cow suggested that the oily formulation achieves concentrations of BP in milk similar to those obtained from a marketed aqueous suspension formulation of PNT. The AUC0-48 and t1/2el of BP in milk after i.m. administration of the marketed aqueous suspension formulation of PNT were 3.56 ± 0.17 mg.h L-1 and 4.9 ± 0.3 h respectively, while the corresponding data for Formulation B were 4.9 ± 1.4 mg.h L-1 and 4.6 ± 1.2 h respectively.
Conclusion: The chemical stability of PNT was greatly enhanced in oily suspensions with around 95% PNT remaining for over 3 months under intermediate storage conditions (30 °C). PNT can be formulated as a physically and chemically stable ready-to-use suspension. This suspension probably gives milk levels of BP comparable with the existing marketed aqueous suspension formulation and a larger animal study is warranted to test this