https://nova.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 Validation of a Flow Cytometry Live Cell-Based Assay to Detect Myelin Oligodendrocyte Glycoprotein Antibodies for Clinical Diagnostics https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46794 Wed 30 Nov 2022 14:31:28 AEDT ]]> Unicellular cyanobacteria are important components of phytoplankton communities in Australia's Northern oceanic ecoregions https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:45143 Trichodesmium. During an oceanographic transect from the Arafura Sea through the Torres Strait to the Coral Sea, we characterized prokaryotic and eukaryotic phytoplankton communities in surface waters using a combination of flow cytometry and Illumina based 16S and 18S ribosomal RNA amplicon sequencing. Similar to observations in other marine regions around Australian, phytoplankton assemblages throughout this entire region were rich in unicellular picocyanobacterial primary producers while picoeukaryotic phytoplankton formed a consistent, though smaller proportion of the photosynthetic biomass. Major taxonomic groups displayed distinct biogeographic patterns linked to oceanographic and nutrient conditions. Unicellular picocyanobacteria dominated in both flow cytometric abundance and carbon biomass, with members of the Synechococcus genus dominating in the shallower Arafura Sea and Torres Strait where chlorophyll a was relatively higher (averaging 0.4 ± 0.2 mg m-3), and Prochlorococcus dominating in the oligotrophic Coral Sea where chlorophyll a averaged 0.13 ± 0.07 mg m-3. Consistent with previous microscopic and pigment-based observations, we found from sequence analysis that a variety of diatoms (Bacillariophyceae) exhibited high relative abundance in the Arafura Sea and Torres Strait, while dinoflagellates (Dinophyceae) and prymnesiophytes (Prymnesiophyceae) were more abundant in the Coral Sea. Ordination analysis identified temperature, nutrient concentrations and water depth as key drivers of the region’s assemblage composition. This is the first molecular and flow cytometric survey of the abundance and diversity of both prokaryotic and picoeukaryotic phytoplankton in this region, and points to the need to include the picocyanobacterial populations as an essential oceanic variable for sustained monitoring in order to better understand the health of these important coastal waters as global oceans change.]]> Wed 26 Oct 2022 13:40:53 AEDT ]]> Investigating aberrant inflammatory signalling in asthma https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:38782 Wed 13 Mar 2024 13:54:22 AEDT ]]> Immunometabolism in obese asthma https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:22041 Wed 11 Apr 2018 16:59:44 AEST ]]> Nontypeable haemophilus influenzae induces sustained lung oxidative stress and protease expression https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:22120 Haemophilus influenzae (NTHi) is a prevalent bacterium found in a variety of chronic respiratory diseases. The role of this bacterium in the pathogenesis of lung inflammation is not well defined. In this study we examined the effect of NTHi on two important lung inflammatory processes 1), oxidative stress and 2), protease expression. Bronchoalveolar macrophages were obtained from 121 human subjects, blood neutrophils from 15 subjects, and human-lung fibroblast and epithelial cell lines from 16 subjects. Cells were stimulated with NTHi to measure the effect on reactive oxygen species (ROS) production and extracellular trap formation. We also measured the production of the oxidant, 3-nitrotyrosine (3-NT) in the lungs of mice infected with this bacterium. NTHi induced widespread production of 3-NT in mouse lungs. This bacterium induced significantly increased ROS production in human fibroblasts, epithelial cells, macrophages and neutrophils; with the highest levels in the phagocytic cells. In human macrophages NTHi caused a sustained, extracellular production of ROS that increased over time. The production of ROS was associated with the formation of macrophage extracellular trap-like structures which co-expressed the protease metalloproteinase-12. The formation of the macrophage extracellular trap-like structures was markedly inhibited by the addition of DNase. In this study we have demonstrated that NTHi induces lung oxidative stress with macrophage extracellular trap formation and associated protease expression. DNase inhibited the formation of extracellular traps.]]> Wed 11 Apr 2018 15:36:56 AEST ]]> Life cycle assessment for the environmental sustainability of the immobilized acid-adapted microalgal technology in iron removal from acid mine drainage https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:44477 Desmodesmus sp. MAS1 and Heterochlorella sp. MAS3, were assessed for their ability in iron (Fe) removal from an AMD sample in nonimmobilized and immobilized systems. Use of free and immobilized cells exhibited 46−48% and 65−79% Fe removal, respectively, after 48 h of incubation. Compared with free cells, immobilized cells exhibited no apparent changes in morphology and granularity, as revealed by flow cytometry analysis, after their exposure to AMD samples. The second derivative spectra from Fourier transform infrared spectroscopy showed vibrational stretching for proteins and hydroxyl groups in immobilized cells. Thus, the immobilization technology offers a protective mechanism in acid-adapted strains against Fe present in AMD samples. Analysis of the immobilized acid-adapted microalgal technology by life cycle assessment (LCA) revealed its environmental sustainability because of less contribution to global warming and limited fossil fuel consumption. We demonstrated that the immobilized acid-adapted microalgal technology is much superior to calcined eggshell−microalgal or conventional limestone systems indicated in the literature for AMD treatment. Thus, this is the first study describing the potential application of microalgal cells entrapped in alginate beads in a greener and economical approach to treat AMD for sustainable mining.]]> Wed 07 Feb 2024 16:37:48 AEDT ]]> Strategies for enumeration of circulating microvesicles on a conventional flow cytometer: counting beads and scatter parameters https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:37665 2 ≥ 0.997). However, TruCount beads produced the most consistent (concentration variation = 3.8%) calculated numbers of plasma CD41+/Annexin V+ MV, which were significantly higher from that calculated using either Flow-Count or CountBright (p < 0.001). The FACSCanto was able to resolve 0.5 μm beads by FSC and 0.16 μm beads by SSC, but there were significantly more background events using SSC compared with FSC (3113 vs. 470; p = 0.008). In general, sample analysis by SSC resulted in significantly higher numbers of MV (p < 0.0001) but was well correlated with enumeration by FSC for all MV subtypes (ρ = 0.62–0.89, p < 0.0001). We conclude that all counting beads provided linear results at concentrations ranging from 6 beads/μl to 100 beads/μl, but TruCount was the most consistent. Using SSC to gate MV events produced high background which negatively affected counting bead enumeration and overall MV calculations. Strategies to reduce SSC background should be employed in order to reliably use this technique.]]> Tue 09 Mar 2021 18:12:55 AEDT ]]> Circulating microvesicles are less procoagulant and carry different miRNA cargo in myelodysplasia https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:42910 Tue 06 Sep 2022 15:49:23 AEST ]]> Circulating microvesicle number, function and small RNA content vary with age, gender, smoking status, lipid and hormone profiles https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:34451 Tue 03 Sep 2019 18:26:31 AEST ]]> Depletion of thiols leads to redox deregulation, production of 4-hydroxinonenal and sperm senescence: a possible role for GSH regulation in spermatozoa https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:42127 P < 0.001). Furthermore, the deleterious effects of GSH depletion using menadione and 1,3 dimethoxy 1,4, naphtoquinone (DMNQ) were able to be prevented by the addition of cysteine, but no other antioxidant. Pre-incubation with cysteine prevented menadione and DMNQ induced damage to sperm membranes after 1 h (P < 0.001; P < 0.05) and after 3 h of incubation (P < 0.001, P < 0.05). Pre-incubation with cysteine ameliorated both the menadione- and DMNQ-induced increase in 4-hydroxynonenal (P < 0.001). As cysteine is a precursor of GSH, we hypothesized that stallion spermatozoa are able to synthesize this tripeptide using exogenous cysteine. To test this hypothesis, we investigated the presence of two enzymes required to synthesize GSH (GSH and GCLC) and using western blotting and immunocytochemistry we detected both enzymes in stallion spermatozoa. The inhibition of GCLC reduced the recovery of GSH by addition of cysteine after depletion, suggesting that stallion spermatozoa may use exogenous cysteine to regulate GSH. Other findings supporting this hypothesis were changes in sperm functionality after BSO treatment and changes in GSH and GSSG validated using HPLC-MS, showing that BSO prevented the increase in GSH in the presence of cysteine, although important stallion to stallion variability occurred and suggested differences in expression of glutamate cysteine ligase. Mean concentration of GSH in stallion spermatozoa was 8.2 ± 2.1 μM/109 spermatozoa, well above the nanomolar ranges per billion spermatozoa reported for other mammals.]]> Thu 25 Aug 2022 12:01:39 AEST ]]> HIV infection is influenced by dynamin at 3 independent points in the viral life cycle https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:31291 Thu 13 Jan 2022 10:28:35 AEDT ]]> Standardization of extracellular vesicle measurements by flow cytometry through vesicle diameter approximation https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:36454 Thu 07 May 2020 13:43:39 AEST ]]> Microparticles in health and disease https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:5366 Sat 24 Mar 2018 07:43:59 AEDT ]]> Correlative analysis of nanoparticle tracking, flow cytometric and functional measurements for circulating microvesicles in normal subjects https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:27930 s, was -0.34 and -0.30 respectively, p<0.05) and positively correlated with the ELISA MP-activity assay (rs=0.42 for both, p<0.05). In addition, endothelial MV levels weakly correlated with white cell counts (rs = 0.27, p<0.05). Conclusions Thrombin generation and flow cytometry for phosphatidylserine or tissue factor expressing MV correlate well as markers for procoagulant activity. A combination of optical or non-optical enumeration as well as functional methods may be required for a complete profiling of circulating MV.]]> Sat 24 Mar 2018 07:36:09 AEDT ]]> Investigating the role of microparticles/ microvesicles/extracellular vesicles in vascular biology, haemostasis and haemopoietic dysregulation https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:34877 Mon 23 Sep 2019 12:38:08 AEST ]]>