Depression, anxiety and worry in young Pacific adults in New Zealand during the COVID-19 pandemic.

OBJECTIVE: To measure symptoms of anxiety, depression and hopelessness in a sample of young Pacific adults living in Auckland, New Zealand during the 2020/2021 COVID-19 pandemic and identify protective factors. METHODS: Participants were 267 Pacific adults (58% female) who completed a survey online. Analyses included descriptive statistics, correlations, linear regression and symptom network analysis. RESULTS: Around 25% of the sample scored in the range for moderate to severe anxiety and 10% for moderate to severe depression on standard measures. Almost 40% indicated that they found the first lockdown very stressful and 55% noted that some members of their family found it stressful. Only 16% worried about COVID-19 and their future quite a bit or constantly, while another 25% worried sometimes. Self-compassion and Pacific Identity had moderate, negative correlations, and Worry about COVID-19 had weak positive correlations, with anxiety, depression, hopelessness and perceived stress. CONCLUSION: These results suggest that, while the prevalence of depression and anxiety are quite high among this population, fostering ethnic identity and self-compassion in Pacific children and adolescents might protect against developing depression and anxiety.

Adaptation to a ketogenic diet modulates adaptive and mucosal immune markers in trained male endurance athletes.

This study examined the effect of short-term adaptation to a ketogenic diet (KD) on resting and post-exercise immune markers. Using a randomized, repeated-measures, crossover design, eight trained, male, endurance athletes ingested a 31-day low carbohydrate (CHO), KD (energy intake: 4% CHO; 78% fat) or their habitual diet (HD) (energy intake: 43% CHO; 38% fat). On days 0 and 31, participants ran to exhaustion at 70% VO2max . A high-CHO (2 g·kg-1 ) meal was ingested prior to the pre-HD, post-HD, and pre-KD trials, with CHO (~55 g·h-1 ) ingested during exercise, whereas a low-CHO (<10 g) meal was ingested prior to the post-KD trial, with fat ingested during exercise. Blood and saliva samples were collected at pre-exercise, exhaustion, and 1 hour post-exhaustion. T-cell-related cytokine gene expression within peripheral blood mononuclear cells (PBMCs) and whole-blood inflammatory cytokine production were determined using 24-hour multi-antigen-stimulated whole-blood cultures. Multi-antigen-stimulated PBMC IFN-γ mRNA expression and the IFN-γ/IL-4 mRNA expression ratio were higher at exhaustion in the post-KD compared with pre-KD trial (P = 0.003 and P = 0.004); however, IL-4 and IL-10 mRNA expression were unaltered (P > 0.05). Multi-antigen-stimulated whole-blood IL-10 production was higher in the post-KD compared with pre-KD trial (P = 0.028), whereas IL-1ß, IL-2, IL-8, and IFN-γ production was lower in the post-HD compared with pre-HD trial (P < 0.01). Salivary immunoglobulin A (SIgA) secretion rate was higher in the post-KD compared with pre-KD trial (P < 0.001). In conclusion, short-term adaptation to a KD in endurance athletes may alter the pro- and anti-inflammatory immune cell cytokine response to a multi-antigen in vitro and SIgA secretion rate.

Risk factors at five-year survival in grade 3 breast cancer: a retrospective observational study of the New Zealand population.

BACKGROUND: Breast cancer is the most common cancer in New Zealand, with approximately 3000 new registrations annually, affecting one in nine women and resulting in more than 600 deaths. This study analyzed data of patients with selected prognostic factors of Nottingham grade 3 tumors over a specified five-year period. The study aimed to identify factors that result in differential survival in the female, New Zealand population. METHOD: This is an observational, retrospective cohort study of prospectively collected data from New Zealand Breast Cancer Register. The selected period of 1st January 2011 to 31st, December 2015 allowed a consistent overlap for a national five-year data of grade 3 breast cancer in New Zealand. Mortality was carried out using univariate Fine-Gray competing risk statistical models. RESULTS: This study showed that women in the older age group (> 70 years) had higher five-year mortality risk (HR: 1.7, 95% CI: 0.9-3.0, p = 0.053). Hormonal receptor analysis showed that ER positive, PR negative, and ER negative, PR negative subjects were at increased risk (HR = 3.5, 95% CI 2.3-5.4, p < 0.001) and (HR = 2.6, 95% CI, 1.8-3.9, p < 0.001) respectively. Molecular subtypes Triple Negative Breast Cancer and Luminal B subjects were at increased risk (HR = 3.0, 95% CI, 1.8-4.7, p < 0.001 and (HR = 3.3, 95% CI, 1.7-6.3, p < 0.001) respectively. HER2 enriched subjects were at a higher, but not significant, risk of five-year mortality compared to luminal A (HR = 1.6, 95% CI, 0.8-3.0, p = 0.10). NZ Europeans were at increased risk (HR = 1.7, 95% CI, 0.8-3.2, p = 0.11), with the highest Cumulative Incidence Function CIF, the largest proportion of HER2 enriched and TNBC across ethnicities.; however, Pacific Islanders experienced the highest HER2 CIF. CONCLUSION: The survival rates for grade 3 breast cancer vary across the selected prognostic factors and ethnicity. The results of this study make an initial contribution to the understanding of grade 3 breast cancer in the New Zealand population.

Predictors of upper respiratory tract symptom risk: Differences between elite rugby union and league players.

This study examined possible predictors of upper respiratory tract symptom (URTS) episodes in elite rugby union and league players (n = 51) during intensive pre-season training. Baseline saliva and blood samples were collected in the first week of pre-season training for analysis of salivary secretory immunoglobulin A (SIgA) and cytomegalovirus. Thereafter, SIgA, URTS, internal training load and self-reported wellness data were repeatedly measured throughout a 10-week pre-season training period. Univariate frailty model analysis, which included 502 observations, was performed for each rugby code for the following independent predictor variables: SIgA concentration, internal training load, total wellness, sleep quantity, sleep quality and stress. Rugby union and league players experienced a similar number of URTS episodes; however, predictors of URTS episodes differed between the codes. No biomarkers or self-reported measures significantly predicted URTS risk in rugby union players, while reductions in self-reported total wellness (HR: 0.731, p = 0.004) and sleep quality (HR: 0.345, p = 0.001) predicted increased URTS risk in rugby league players. The findings from this study highlight that factors influencing URTS risk are perhaps sport specific and this may be attributed to different sporting demands and/or different management of players by team-practitioners.

Effect of anticoagulants on farmed giant kokopu, Galaxias argenteus (Gmelin 1789) haematological parameters and erythrocyte fragility.

We sought to determine a compatible anticoagulant for routine haematological and physiological assessments with giant kokopu (Galaxias argenteus), an endemic New Zealand fish. We observed that blood treated with lithium heparin (LH) rapidly coagulated and haemolysed, making it unsuitable for G. argenteus. Dipotassium ethylenediaminetetraacetic acid (K2 EDTA) and trisodium citrate (citrate) effectively prevented blood coagulation. K2 EDTA-treated erythrocytes exhibited the least mean haemolysis and mean corpuscular fragility. Further studies into prolonged storage effects of citrate and K2 EDTA are recommended to find a compatible anticoagulant for use with G. argenteus blood.

Haematological and metabolic profiles associated with age and sex in giant kokopu (Galaxias argenteus) (Gmelin 1789) broodstock.

This study characterized selected peripheral blood (PB) haematological parameters, liver, serum and muscle metabolic features in 3- and 5-year-old male and female giant kokopu (Galaxias argenteus) broodstock reared indoor at 16°C. Sex and age did not affect PB total cell count and haematocrit values. Nonetheless, higher erythrocytes in 5-year-old fish, elevated thrombocyte and lymphocyte counts in 3-year-old fish indicate age-specific cellular regulation. Higher thrombocyte counts in female fish suggest sex-specific regulation. At a metabolic level, liver abundance for long chain saturated fatty acids (FAs) was higher in males, whereas females had elevated levels of polyunsaturated FAs. Essential and non-essential amino acids (AAs) in liver and serum were also elevated in females compared to males. These findings suggest differential allocation of FAs and AAs to reflect requirements for gonadal, development and provisioning. Similarly, age significantly resulted in higher liver and serum abundances of some non-essential AAs in 3-year-olds compared to 5-year-old fish, suggesting higher metabolism in younger fish. Overall, results enhance our understanding of sex- and age-based differences in fish haematology, muscle, liver, and serum metabolite profiles in healthy G. argenteus. Future studies should carefully consider potential age- and sex-specific differences in metabolic responses.

Immune response in probiotic-fed New Zealand black-footed abalone (Haliotis iris) under Vibrio splendidus challenge.

Vibriosis disease is a major constraint for sustainable molluscan aquaculture. Development of strategies to enhance disease resistance during grow out would greatly reduce stock mortality and boost production yields. In this study, New Zealand black-footed abalone (Haliotis iris) were fed a commercial diet enhanced with multi-strain probiotics (Exiguobacterium JHEb1, Vibrio JH1 and Enterococcus JHLDc) for four months, then challenged with an injection of pathogenic Vibrio splendidus. Host immune responses in haemocytes were characterized using flow cytometry by measuring total haemocyte counts (THC) and viability, degree of apoptosis, and production of reactive oxygen species (ROS) 48 h post-challenge. Probiotic-fed abalone had significantly higher survival rates compared to control animals after the bacterial challenge. Infected probiotic-fed abalone also had significantly higher haemocyte viabilities, slightly lower proportions of haemocytes undergoing early apoptosis, and lower proportions of ROS-producing haemocytes compared to infected control-fed abalone. In addition, metabolite profiles of muscle tissues generated via gas chromatography-mass spectrometry (GC-MS) delivered complimentary evidence to support a perturbed ROS-regulatory system in infected abalone through changes in key metabolites associated with glutathione biosynthesis. The results of this study provide valuable information to assist in farm management practices, leading to enhance production and sustainability of the New Zealand abalone aquaculture industry.

Acute hyperketonaemia alters T-cell-related cytokine gene expression within stimulated peripheral blood mononuclear cells following prolonged exercise.

PURPOSE: We investigated the effect of the racemic ß-hydroxybutyrate precursor, R,S-1,3-butanediol (BD), on T-cell-related cytokine gene expression within stimulated peripheral blood mononuclear cells (PBMC) following prolonged, strenuous exercise. METHODS: A repeated-measures, randomised, crossover study was conducted in nine healthy, trained male cyclists (age, 26.7 ± 5.2 years; VO2peak, 63.9 ± 2.5 mL kg-1 min-1). Participants ingested 0.35 g kg-1 of BD or placebo 30 min before and 60 min during 85 min of steady-state (SS) exercise, which preceded a ~ 30 min time-trial (TT) (7 kJ kg-1). Blood samples were collected at pre-supplement, pre-exercise, post-SS, post-TT and 1-h post-TT. Whole blood cultures were stimulated with Staphylococcal enterotoxin B (SEB) for 24 h to determine T-cell-related interleukin (IL)-4, IL-10 and interferon (IFN)-γ mRNA expression within isolated PBMCs in vitro. RESULTS: Serum cortisol, total circulating leukocyte and lymphocyte, and T-cell subset concentrations were similar between trials during exercise and recovery (all p > 0.05). BD ingestion increased T-cell-related IFN-γ mRNA expression compared with placebo throughout exercise and recovery (p = 0.011); however, IL-4 and IL-10 mRNA expression and the IFN-γ/IL-4 mRNA expression ratio were unaltered (all p > 0.05). CONCLUSION: Acute hyperketonaemia appears to transiently amplify the initiation of the pro-inflammatory T-cell-related IFN-γ response to an immune challenge in vitro during and following prolonged, strenuous exercise; suggesting enhanced type-1 T-cell immunity at the gene level.

Metabolic and immune responses of Chinook salmon (Oncorhynchus tshawytscha) smolts to a short-term poly (I:C) challenge.

Polyinosinic:polycytidylic acid [poly (I:C)] was administered in vivo to Chinook salmon (Oncorhynchus tshawytscha) post-smolts to determine the immune responses on haematological and cellular functional parameters, including spleen (SP), head kidney (HK) and red blood cell (RBC) cytokine expression, as well as serum metabolomics. Poly (I:C) in vivo (24 h exposure) did not affect fish haematological parameters, leucocyte phagocytic activity and phagocytic index, reactive oxygen species and nitric oxide production. Gas chromatography-mass spectrometry-based metabolomics revealed that poly (I:C) significantly altered the serum biochemistry profile of 25 metabolites. Metabolites involved in the branched-chain amino acid/glutathione and transsulphuration pathways and phospholipid metabolism accumulated in poly (I:C)-treated fish, whereas those involved in the glycolytic and energy metabolism pathways were downregulated. At cytokine transcript level, poly (I:C) induced a significant upregulation of antiviral ifnγ in HK and Mx1 protein in HK, SP and RBCs. This study provides evidence for poly (I:C)-induced, immune-related biomarkers at metabolic and molecular levels in farmed O. tshawytscha in vivo. These findings provide insights into short-term effects of poly (I:C) at haematological, innate and adaptive immunity and metabolic levels, setting the stage for future studies.

Advances in salmonid fish immunology: A review of methods and techniques for lymphoid tissue and peripheral blood leucocyte isolation and application.

Evaluating studies over the past almost 40 years, this review outlines the current knowledge and research gaps in the use of isolated leucocytes in salmonid immunology understanding. This contribution focuses on the techniques used to isolate salmonid immune cells and popular immunological assays. The paper also analyses the use of leucocytes to demonstrate immunomodulation following dietary manipulation, exposure to physical and chemical stressors, effects of pathogens and parasites, vaccine design and application strategies assessment. We also present findings on development of fish immune cell lines and their potential uses in aquaculture immunology. The review recovered 114 studies, where discontinuous density gradient centrifugation (DDGC) with Percoll density gradient was the most popular leucocyte isolation method. Fish head kidney (HK) and peripheral blood (PB) were the main sources of leucocytes, from rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar). Phagocytosis and respiratory burst were the most popular immunological assays. Studies used isolated leucocytes to demonstrate that dietary manipulations enhance fish immunity, while chemical and physical stressors suppress immunity. In addition, parasites, and microbial pathogens depress fish innate immunity and induce pro-inflammatory cytokine gene transcripts production, while vaccines enhance immunity. This review found 10 developed salmonid cell lines, mainly from S. salar and O. mykiss HK tissue, which require fish euthanisation to isolate. In the face of high costs involved with density gradient reagents, the application of hypotonic lysis in conjunction with mico-volume blood methods can potentially reduce research costs, time, and using nonlethal and ethically flexible approaches. Since the targeted literature review for this study retrieved no metabolomics study of leucocytes, indicates that this approach, together with traditional technics and novel flow cytometry could help open new opportunities for in vitro studies in aquaculture immunology and vaccinology.

In vitro immune response of chinook salmon (Oncorhynchus tshawytscha) peripheral blood mononuclear cells stimulated by bacterial lipopolysaccharide.

We investigated cellular functional and targeted immune cytokine responses of farmed Chinook salmon (Oncorhynchus tshawytscha) peripheral blood mononuclear cells (PBMCs) in vitro to LPS from Escherichia coli (E. coli) serotypes O111: B4 and O55: B5, and a phorbol ester phorbol 12-myristate 13-acetate (PMA). Bacterial LPS and PMA significantly (p < 0.05) induced reactive oxygen species (ROS) production in O. tshawytscha PBMCs, and enhanced by interferon (IFN)-inducible cytokine production. Cellular phagocytosis was significantly enhanced with PMA and E. coli serotype O111: B4 LPS after 1 and 2 h respectively. At the molecular level, LPS and PMA significantly (p < 0.05) upregulated pro-inflammatory cytokine gene transcripts for IFNγ, TNF-α, and anti-inflammatory IL-10, 24 h post-stimulation. This response is postulated to be mediated via the MyD88 and TRIF pathways in TLR4, or synergistic TLR1 and TLR2 receptors. This is the first report of LPS induced immune related in vitro responses in farmed O. tshawytscha PBMCs.

Characterisation of Chinook salmon (Oncorhynchus tshawytscha) blood and validation of flow cytometry cell count and viability assay kit.

New Zealand Chinook salmon (Oncorhynchus tshawytscha) industry has great potential for growth and expansion. While production is relatively free of health problems, there is limited literature on haematology, and immunological tools to safeguard against possible future health threats. The current study aim was to characterise New Zealand farmed O. tshawytscha peripheral blood cellular composition, develop a micro-volume method to isolate peripheral blood mononuclear cells (PBMCs) and validate a microcapillary flow cytometry assay kit for PBMC cell count and viability assessment. We used light microscopy to characterise peripheral blood and PBMC cellular composition in combination with a flow cytometer Sysmex XT 2000i Haematology Analyser. ImageJ version 1.52 was used for cell size characterisation of freshly stained blood. The stability of PBMCs stained with the Muse® Cell Count and Viability Assay Kit and the Trypan blue assay stains were studied at 4 °C and 21 °C for 60 min; while the Muse® Cell Count and Viability Assay Kit was validated against the Trypan blue assay haemocytometer chamber to assess PBMC count and viability. Findings showed that O. tshawytscha smolt yearlings had total blood cell counts in the range of 1.9-2.7 × 106 µL-1. Differential cell counts revealed five cell types, comprising 97.18% erythrocytes, 2.03% lymphocytes, 0.67% thrombocytes, 0.09% monocytes, and unquantifiable neutrophils. Using micro-volumes of blood and Lymphoprep™, we successfully isolated fish PBMCs. Significantly, stained PBMCs remained stable for up to 45 min at 4 °C and 21 °C; while validation of the Muse® protocol showed that this microfluidic instrument delivered more accurate and precise viability results than the haemocytometer. The Muse® protocol is rapid, easy to use, has quick calibration steps, and is suitable for field use to facilitate onsite sample processing. These findings pave the way for future assessments of fish health and in vitro immunological studies in O. tshawytscha.

The Effect of 1,3-Butanediol on Cycling Time-Trial Performance.

This study investigated the effect of the racemic ß-hydroxybutyrate (ßHB) precursor, R,S-1,3-butanediol (BD), on time-trial (TT) performance and tolerability. A repeated-measures, randomized, crossover study was conducted in nine trained male cyclists (age, 26.7 ± 5.2 years; body mass, 69.6 ± 8.4 kg; height, 1.82 ± 0.09 m; body mass index, 21.2 ± 1.5 kg/m2; VO2peak,63.9 ± 2.5 ml·kg-1·min-1; Wmax, 389.3 ± 50.4 W). Participants ingested 0.35 g/kg of BD or placebo 30 min before and 60 min during 85 min of steady-state exercise, which preceded a ∼25- to 35-min TT (i.e., 7 kJ/kg). The ingestion of BD increased blood D-ßHB concentration throughout exercise (0.44-0.79 mmol/L) compared with placebo (0.11-0.16 mmol/L; all p < .001), which peaked 1 hr following the TT (1.38 ± 0.35 vs. 0.34 ± 0.24 mmol/L; p < .001). Serum glucose and blood lactate concentrations were not different between trials (all p > .05). BD ingestion increased oxygen consumption and carbon dioxide production after 20 min of steady-state exercise (p = .002 and p = .032, respectively); however, no further effects on cardiorespiratory parameters were observed. Within the BD trial, moderate to severe gastrointestinal symptoms were reported in five participants, and low levels of dizziness, nausea, and euphoria were reported in two participants. However, this had no effect on TT duration (placebo, 28.5 ± 3.6 min; BD, 28.7 ± 3.2 min; p = .62) and average power output (placebo, 290.1 ± 53.7 W; BD, 286.4 ± 45.9 W; p = .50). These results suggest that BD has no benefit for endurance performance.

Organisational culture: the hidden operand in clinical laboratories.

PURPOSE: The purpose of this paper is to present organisational cultural determinants that can influence total quality management (TQM) in clinical laboratories. DESIGN/METHODOLOGY/APPROACH: This is a viewpoint paper using evidence provided by a literature research about cultural patterns using Competing Values Framework to explain the relationship between organisational culture and TQM. FINDINGS: Cultural aspects likely to enhance creativity and innovation are considered as incentives in promoting cultural transformation. TQM in the average modern clinical laboratory requires a long overdue transformational change in values, culture and attitude. SOCIAL IMPLICATIONS: Valuing people, making up an organisation, is expected to enhance TQM. ORIGINALITY/VALUE: This paper provokes a shift in thinking among traditional clinical laboratory managers and results in a win-win for both staff and total quality outcomes.

T-cells and their cytokine production: The anti-inflammatory and immunosuppressive effects of strenuous exercise.

Strenuous exercise bouts and heavy training are associated with a heightened anti-inflammatory state and a transient suppression of several immune components. In turn, many athletes are susceptible to illness, particularly upper respiratory symptoms (e.g. cough, sore throat, running nose). T-lymphocytes (T-cells) are important for orchestrating the immune response and can be categorised into subsets according to their phenotypical characteristics resulting from polarisation (i.e. type-1, type-2 and regulatory T-cells). Each T-cell subset has a unique functional role, including their capacity to produce pro- and anti-inflammatory cytokines in response to an immune challenge. Prolonged and exhaustive exercise typically reduces peripheral blood type-1 T-cell number and their capacity to produce the pro-inflammatory cytokine, interferon-γ. Moreover, heavy training loads are associated with elevated numbers of resting peripheral blood type-2 and regulatory T-cells, which characteristically produce the anti-inflammatory cytokines, interleukin-4 and interleukin-10, respectively. This appears to increase the risk of upper respiratory symptoms, potentially due to the cross-regulatory effect of interleukin-4 on interferon-γ production and immunosuppressive action of IL-10. Catecholamines significantly influence the number of peripheral blood T-cells in response to exercise. Whereas, glucocorticoids and prostaglandin E2 promote the production of anti-inflammatory cytokines by T-cells. In summary, strenuous exercise bouts and heavy training shifts T-cell immunity towards an anti-inflammatory state. This impairs the ability of the immune system to mount an inflammatory response to an immune challenge, which may weaken defences against intracellular pathogens (e.g. viruses), and increase the risk of infection and viral reactivation.

Effect of antiaggregants on the in vitro viability, cell count and stability of abalone (Haliotis iris) haemocytes.

The ability to successfully prepare and preserve haemocyte cells for microscopy and flow cytometry is critical for the investigation of animal immune systems. In this study, we observed the total cell count, in vitro viability and stability of New Zealand black-footed abalone (Haliotis iris) haemocytes with different antiaggregants and handling protocols. Haemocyte stability was evaluated by direct observation of haemocytes under the microscope and calculating the aggregation index. Haemocyte counts and viability were measured via flow cytometry and tested for the effect of different antiaggregants (Alsever's solution at three concentrations, and specialised blood collection tubes containing lithium heparin and K2EDTA) at different temperatures and storage times. Results showed that Alsever's solution is an effective antiaggregant at haemolymph:antiaggregant dilution ratios of 1:1, 1:2 and 1:3. Lithium heparin was ineffective as an antiaggregant, whereas K2EDTA was similarly as effective as Alsever's solution. The influence of different mixing techniques (vortex, pipetting and flipping) were subsequently tested using the K2EDTA Microtainer® tubes, revealing that proper mixing should be performed immediately. High cell viability can be achieved by mixing samples by either 10 s of vortexing (1000 rpm), 10 times pipetting or 20 times flipping. The in vitro storage of abalone haemocytes in AS and K2EDTA as antiaggregants at ambient room temperature was highly effective for up to 24 h (75-85% viability; 0.05-0.15 aggregation index) and is recommended for haemocyte studies in H. iris. Utilization of K2EDTA Microtainer® tubes were advantageous since they are more cost effective compared to Alsever's solution, and samples can be prepared more efficiently.

Multi-strain probiotics enhance immune responsiveness and alters metabolic profiles in the New Zealand black-footed abalone (Haliotis iris).

We assessed whether dietary administration of a multi-strain probiotic (Exiguobacterium JHEb1, Vibrio JH1 and Enterococcus JHLDc) lead to enhanced immune responsiveness in juvenile New Zealand black-footed abalone (Haliotis iris). Two groups of abalone were fed (1% body weight per day) over a four-month period with different diets. The control diet consisted of a standard commercial pellet feed (AbMax 16), whereas the treatment diet was additionally enriched with the probiotic mix. At the end of the experiment, probiotic-fed animals showed improved growth compared with control-fed abalone in length (32.3% vs 22.3%), width (31.9% vs 20.7%) and wet weight (109.6% vs 72.8%), respectively. Haemolymph sampling was conducted at the beginning of the experiment and after 2 and 4 months. Haemolymph samples were analysed for total haemocyte count (THC) and viability, presence of apoptotic cells and production of Reactive Oxygen Species (ROS). Compared with control abalone, probiotic-fed abalone had significantly higher THC (1.9 × 106 vs 5.6 × 105 cells), higher viability (90.8% vs 75.6%), higher percentage of ROS-positive cells (19.4% vs 0.5%) and higher numbers of non-apoptotic cells (88.0% vs 78.0%), respectively. These results indicate that the probiotic-enriched diet enhanced the immunostimulatory mechanisms, with a simultaneous low-level up-regulation of ROS production as a priming mechanism of the antibacterial defence system. Metabolomics-based profiling of foot muscle tissue additionally revealed that probiotic-fed abalone differentially expressed 17 unique metabolites, including amino acids, fatty acids and TCA cycle related compounds. These data suggest that the probiotic-supplemented diet can also alter central carbon metabolic processes, which may improve the survival, as well as the growth of abalone.

Metabolic and immunological responses of male and female new Zealand Greenshell™ mussels (Perna canaliculus) infected with Vibrio sp.

Massive mortalities due to pathogens are routinely reported in bivalve cultivation that have significant economic consequences for the global aquaculture industry. However, host-pathogen interactions and infection mechanisms that mediate these interactions are poorly understood. In addition, gender-specific immunological responses have been reported for some species, but the reasons for such differences have not been elucidated. In this study, we used a GC/MS-based metabolomics platform and flow cytometry approach to characterize metabolic and immunological responses in haemolymph of male and female mussels (Perna canaliculus) experimentally infected with Vibrio sp. Sex-based differences in immunological responses were identified, with male mussels displaying higher mortality, oxidative stress and apoptosis after pathogen exposure. However, central metabolic processes appeared to be similar between sexes at 24 h post injection with Vibrio sp. DO1. Significant alterations in relative levels of 37 metabolites were detected between infected and uninfected mussels. These metabolites are involved in major perturbations on the host's innate immune system. In addition, there were alterations of seven metabolites in profiles of mussels sampled on the second day and mussels that survived six days after exposure. These metabolites include itaconic acid, isoleucine, phenylalanine, creatinine, malonic acid, glutaric acid and hydroxyproline. Among these, itaconic acid has the potential to be an important biomarker for Vibrio sp. DO1 infection. These findings provide new insights on the mechanistic relationship between a bivalve host and a pathogenic bacterium and highlight the need to consider host sex as a biological variable in future immunological studies.

Fucoidan Extracted from the New Zealand Undaria pinnatifida-Physicochemical Comparison against Five Other Fucoidans: Unique Low Molecular Weight Fraction Bioactivity in Breast Cancer Cell Lines.

Fucoidan, the complex fucose-containing sulphated polysaccharide varies considerably in structure, composition, and bioactivity, depending on the source, species, seasonality, and extraction method. In this study, we examined five fucoidans extracted from the same seaweed species Undaria pinnatifida but from different geological locations, and compared them to the laboratory-grade fucoidan from Sigma (S). The five products differed in molecular composition. The amount of over 2 kDa low molecular weight fraction (LMWF) of the New Zealand crude fucoidan (S1) was larger than that of S, and this fraction was unique, compared to the other four fucoidans. The difference of molecular compositions between S and S1 explained our previous observation that S1 exhibited different anticancer profile in some cancer cell lines, compared with S. Since we observed this unique LMWF, we compared the cytotoxic effects of a LMWF and a high molecular weight fucoidan (HMWF) in two breast cancer cell lines-MCF-7 and MDA-MB-231. Results indicated that the molecular weight is a critical factor in determining the anti-cancer potential of fucoidan, from the New Zealand U. pinnatifida, as the LMWF exhibited a dose-dependent inhibition on the proliferation of breast cancer cells, significantly better than the HMWF, in both cell lines. A time-dependent inhibition was only observed in the MCF-7. Induction of caspase-dependent apoptosis was observed in the MDA-MB-231 cells, through the intrinsic apoptosis pathway alone, or with the extrinsic pathway. LMWF stimulated a dose-dependent NOS activation in the MDA-MB-231 cells. In conclusion, the fucoidan extracted from the New Zealand U. pinnatifida contains a unique LMWF, which could effectively inhibit the growth of breast cancer cell lines. Therefore, the LMWF from New Zealand U. pinnatifida could be used as a supplement cancer treatment.