Physical Sciences and Mathematics Commons^™

Environmental Dna Identifies Coastal Plant Community Shift 1,000 Years Ago In Torrens Island, South Australia, Nicole R. Foster, Alice R. Jones, Oscar Serrano, Anna Lafratta, Paul S. Lavery, Kor-Jent Van Dijk, Ed Biffin, Bronwyn M. Gillanders, Jennifer Young, Pere Masque, Patricia S. Gadd, Geraldine E. Jacobsen, Atun Zawadzki, Andria Greene, Michelle Waycott

Research outputs 2022 to 2026

Anthropogenic activities are causing detrimental changes to coastal plants– namely seagrass, mangrove, and tidal marshes. Looking beyond recent times to past vegetation dynamics is critical to assess the response and resilience of an environment to change. Here, we develop a high-resolution multi-proxy approach, providing a new evidence base to decipher long-term change in coastal plant communities. Combining targeted environmental DNA analysis with chemical analysis of soils, we reconstructed 4,000 years of change at a temperate wetland on Torrens Island South Australia and identified an ecosystem shift that occurred ~ 1000 years ago. What was once a subtidal seagrass system shifted …

Conformational Dynamics Associated With Ligand Binding To Vertebrate Hexa-Coordinate Hemoglobins, Luisana Astudillo

FIU Electronic Theses and Dissertations

Neuroglobin (Ngb) and cytoglobin (Cygb) are two new additions to the globin family, exhibiting heme iron hexa-coordination, a disulfide bond and large internal cavities. These proteins are implicated in cytoprotection under hypoxic-ischemic conditions, but the molecular basis of their cytoprotective function is unclear.

Herein, a photothermal and spectroscopic study of the interactions of diatomic ligands with Ngb, Cygb, myoglobin and hemoglobin is presented. The impact of the disulfide bond in Ngb and Cygb and role of conserved residues in Ngb His64, Val68, Cys55, Cys120 and Tyr44 on conformational dynamics associated with ligand binding/dissociation were investigated. Transient absorption and photoacoustic calorimetry …

Translocation Of The Eastern Bristlebird 1: Radio-Tracking Of Post-Release Movements, David Bain, Kris French, Jack Baker, Jean Clarke

Faculty of Science - Papers (Archive)

Translocating birds to a new area of habitat to restore or supplement depleted populations may pose a significant threat to the translocated individuals. While for many species, translocated individuals appear to move larger distances than resident animals, species with poor dispersal capacity may be restricted in movements and translocation methods may need to accommodate differences in movements to ensure success. In this study, designed to provide insights to inform our broader programme of translocations in New South Wales, Australia, we investigated post-release movements in the endangered, semi-flightless Eastern Bristlebird (Dasyornis brachypterus). We predicted that movements would be minimal, with few …

Process-Evaluation Of Tropospheric Humidity Simulated By General Circulation Models Using Water Vapor Isotopologues: 1. Comparison Between Models And Observations, Camille Risi, David Noone, John Worden, Christian Frankenberg, Gabriele Stiller, Michael Kiefer, Bernd Funke, Kaley Walker, Peter Bernath, Matthias Schneider, Debra Wunch, Vanessa Sherlock, Nicholas M. Deutscher, David W. Griffith, Paul O. Wennberg, Kimberly Strong, Dan Smale, Emmanuel Mahieu, Sabine Barthlott, Frank Hase, Omar Garcia, Justus Notholt, Thorsten Warneke, Geoffrey Toon, David Sayres, Sandrine Bony, Jeonghoon Lee, Derek Brown, Ryu Uemura, Christophe Sturm

Faculty of Science - Papers (Archive)

[1] The goal of this study is to determine how H2O and HDO measurements in water vapor can be used to detect and diagnose biases in the representation of processes controlling tropospheric humidity in atmospheric general circulation models (GCMs). We analyze a large number of isotopic data sets (four satellite, sixteen ground-based remote-sensing, five surface in situ and three aircraft data sets) that are sensitive to different altitudes throughout the free troposphere. Despite significant differences between data sets, we identify some observed HDO/H2O characteristics that are robust across data sets and that can be used to evaluate models. We evaluate …

Activation Of The Damage-Associated Molecular Pattern Receptor P2x7 Induces Interleukin-1b Release From Canine Monocytes, Iman Jalilian, Michelle Peranec, Belinda L. Curtis, Aine Seavers, Mari Spildrejorde, Vanessa Sluyter, Ronald Sluyter

Faculty of Science - Papers (Archive)

P2X7, a damage-associated molecular pattern receptor and adenosine 5'-triphosphate (ATP)-gated cation channel, plays an important role in the activation of the NALP3 inflammasome and subsequent release of interleukin (IL)-1β from human monocytes; however its role in monocytes from other species including the dog remains poorly defined. This study investigated the role of P2X7 in canine monocytes, including its role in IL-1β release. A fixed-time flow cytometric assay demonstrated that activation of P2X7 by extracellular ATP induces the uptake of the organic cation, YO-PRO-1²⁺, into peripheral blood monocytes from various dog breeds, a process impaired by the specific P2X7 …

P2x7 Receptor Activation Mediates Organic Cation Uptake Into Human Myeloid Leukaemic Kg-1 Cells, Safina Gadeock, Aleta Pupovac, Vanessa Sluyter, Mari Spildrejorde, Ronald Sluyter

Faculty of Science - Papers (Archive)

The P2X7 purinergic receptor is an ATP-gated cation channel with an emerging role in neoplasia. In this study we demonstrate that the human KG-1 cell line, a model of acute myelogenous leukaemia, expresses functional P2X7. RT-PCR and immunochemical techniques demonstrated the presence of P2X7 mRNA and protein respectively in KG-l cells, as well as in positive control multiple myeloma RPMI 8226 cells. Flow cytometric measurements demonstrated that ATP induced ethidium(+) uptake into KG-l cells suspended in sucrose medium (EC(50) of ∼3 μM), but not into cells in NaCl medium. In contrast, ATP induced ethidium(+) uptake into RPMI 8226 cells suspended …

Synthesis And Anti-Leukaemic Activity Of Pyrrolo[3,2,1-Hi]Indole-1,2- Diones, Pyrrolo[3,2,1-Ij]Quinoline-1,2-Diones And Other Polycyclic Isatin Derivatives, Lidia Matesic, Julie M. Locke, Kara Vine, Marie Ranson, John B. Bremner, Danielle Skropeta

Faculty of Science - Papers (Archive)

To further expand the structure–cytotoxic activity relationships of isatin derivatives and to reduce flexibility in substituent groups at nitrogen, 20 analogues incorporating a ring system between the N1 and C7 atoms of isatin were prepared using a variety of synthetic strategies. This yielded pyrroloindole-, pyrroloquinoline-, pyrroloacridine-, pyrrolophenanthridine- and benzopyrrolophenanthridine-based systems with embedded isatin moieties, the latter possessing a novel carbon skeleton. These compounds were subsequently assessed for their in vitro cytotoxicity against human U937 lymphoma cells, with the brominated pyrroloacridine dione 27 showing the most promising activity (IC50 3.01 μM) after 24 h.

Polycationic Glycosides, Robert Engel, Ishrat Ghani, Diego Montenegro, Marie Thomas, Barbara Klaritch-Vrana, Alejandra Castaño, Laura Friedman, Jay Leb, Leah Rothman, Heidi Lee, Craig Capodiferro, Daniel Ambinder, Eve Cere, Christopher Awad, Faiza Sheikh, Jaimelee Rizzo, Lisa-Marie Nisbett, Erika Testani, Karin Melkonian

Publications and Research

Cationic lipids have long been known to serve as antibacterial and antifungal agents. Prior efforts with attachment of cationic lipids to carbohydrate-based surfaces have suggested the possibility that carbohydrate-attached cationic lipids might serve as antibacterial and antifungal pharmaceutical agents. Toward the understanding of this possibility, we have synthesized several series of cationic lipids attached to a variety of glycosides with the intent of generating antimicrobial agents that would meet the requirement for serving as a pharmaceutical agent, specifically that the agent be effective at a very low concentration as well as being biodegradable within the organism being treated. The initial …

Extracellular Chaperones Modulate The Effects Of Alzheimer's Patient Cerebrospinal Fluid On A Beta(1-42) Toxicity And Uptake , Justin J. Yerbury, Mark R. Wilson

Faculty of Science - Papers (Archive)

Alzheimer's disease is characterised by the inappropriate death of brain cells and accumulation of the A beta peptide in the brain. Thus, it is possible that there are fundamental differences between Alzheimer's disease patients and healthy individuals in their abilities to clear A beta from brain fluid and to protect neurons from A beta toxicity. In the present study, we examined (1) the cytotoxicity of Alzheimer's disease cerebrospinal fluid (CSF) compared to control CSF, (2) the ability of Alzheimer's disease and control CSF to protect cells from A beta toxicity and to promote cell-mediated clearance of A beta and lastly …

Differential Endocytosis Of Tissue Plasminogen Activator By Serpins Pai-1 And Pai-2 On Human Peripheral Blood Monocytes, Jodi A. Lee, David Croucher, Marie Ranson

Faculty of Science - Papers (Archive)

Generation of the broad spectrum protease plasmin is facilitated by the tissue (t-PA) and urokinase (u-PA) plasminogen activators, within multiple physiological and disease states. Finely tuned control of this proteolytic cascade is exerted by the plasminogen activator inhibitors type-1 (PAI-1/SERPINE1) and 2 (PAI-2/SERPINB2). Expression of this network of activators and inhibitors by cells of myeloid lineage appears to be highly interchangeable between physiological environments, and whilst the role of PAI-1 and PAI-2 in regulating u-PA-dependent functions is well established, the interaction between t-PA and PAI-2 on these cell types is poorly characterised. To this end, we used freshly isolated peripheral …

Reaction Of The C2h Radical With 1-Butyne (C4h6): Low Temperature Kinetics And Isomer-Specific Product Detection, Satchin Soorkia, Adam J. Trevitt, Talitha M. Selby, David L. Osborn, Craig A. Taatjes, Kevin R. Wilson, Stephen R. Leone

Faculty of Science - Papers (Archive)

No abstract provided.

Distribution Of Class 1 Integrons With Is26-Mediated Deletions In Their 3'-Conserved Segments In Escherichia Coli Of Human And Animal Origin., Fay E. Dawes, Alexander Kuzevski, Karl A Bettelheim, Michael A Hornitzky, Steven P Djordjevic, Mark J. Walker

Faculty of Science - Papers (Archive)

Class 1 integrons play a role in the emergence of multi-resistant bacteria by facilitating the recruitment of gene cassettes encoding antibiotic resistance genes. 512 E. coli strains sourced from humans (n = 202), animals (n = 304) and the environment (n = 6) were screened for the presence of the intI1 gene. In 31/79 integron positive E. coli strains, the gene cassette regions could not be PCR amplified using standard primers. DNA sequence analysis of 6 serologically diverse strains revealed atypical integrons harboured the dfrA5 cassette gene and only 24 bp of the integron 3'-conserved segment (CS) remained, due to …

The Repressor Element 1-Silencing Transcription Factor Regulates Heart-Specific Gene Expression Using Multiple Chromatin-Modifying Complexes, Andrew J. Bingham, Lezanne Ooi, Lukasz Kozera, Edward White, Ian C. Wood

Faculty of Science - Papers (Archive)

Cardiac hypertrophy is associated with a dramatic change in the gene expression profile of cardiac myocytes. Many genes important during development of the fetal heart but repressed in the adult tissue are reexpressed, resulting in gross physiological changes that lead to arrhythmias, cardiac failure, and sudden death. One transcription factor thought to be important in repressing the expression of fetal genes in the adult heart is the transcriptional repressor REST (repressor element 1-silencing transcription factor). Although REST has been shown to repress several fetal cardiac genes and inhibition of REST function is sufficient to induce cardiac hypertrophy, the molecular mechanisms …

Infrared Spectra Of The Li +_(H 2)N(N=1-3) Cation Complexes, C Emmeluth, B L. J Poad, C D. Thompson, G H. Weddle, E J. Bieske

Faculty of Science - Papers (Archive)

The Li⁺–(H₂)_n n = 1–3 complexes are investigated through infrared spectra recorded in the H–H stretch region (3980–4120 cm⁻¹) and through ab initio calculations at the MP2∕aug-cc-pVQZ level. The rotationally resolved H–H stretch band of Li⁺–H₂ is centered at 4053.4 cm⁻¹ [a −108 cm⁻¹ shift from the Q₁(0) transition of H₂]. The spectrum exhibits rotational substructure consistent with the complex possessing a T-shaped equilibrium geometry, with the Li⁺ ion attached to a slightly perturbed H₂ molecule. Around 100 rovibrational transitions belonging to …

Widespread Disruption Of Repressor Element-1 Silencing Transcription Factor/Neuron-Restrictive Silencer Factor Occupancy At Its Target Genes In Huntington's Disease, Chiara Zuccato, Nikolai D. Belyaev, Paola Conforti, Lezanne Ooi, Marzia Tartari, Evangelia Papadimou, Marcy Macdonald, Elisa Fossale, Scott Zeitlin, Noel J. Buckley, Elena Cattaneo

Faculty of Science - Papers (Archive)

Huntingtin is a protein that is mutated in Huntington's disease (HD), a dominant inherited neurodegenerative disorder. We previously proposed that, in addition to the gained toxic activity of the mutant protein, selective molecular dysfunctions in HD may represent the consequences of the loss of wild-type protein activity. We first reported that wild-type huntingtin positively affects the transcription of the brain-derived neurotrophic factor (BDNF) gene, a cortically derived survival factor for the striatal neurons that are mainly affected in the disease. Mutation in huntingtin decreases BDNF gene transcription. One mechanism involves the activation of repressor element 1/neuron-restrictive silencer element (RE1/NRSE) located …