ORCID Profile
0000-0001-7858-1130
Current Organisation
University of Queensland
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Publisher: Public Library of Science (PLoS)
Date: 21-10-2011
Publisher: Springer Science and Business Media LLC
Date: 27-02-2010
Publisher: Springer Science and Business Media LLC
Date: 08-2019
DOI: 10.1038/S41467-019-11367-7
Abstract: Many habitat-building corals undergo mass synchronous spawning events. Yet, despite the enormous amounts of larvae produced, larval dispersal from a single spawning event and the reliability of larval supply are highly dependent on vagaries of ocean currents. However, colonies from the same population will occasionally spawn over successive months. These split spawning events likely help to realign reproduction events to favourable environmental conditions. Here, we show that split spawning may benefit corals by increasing the reliability of larval supply. By modelling the dispersal of coral larvae across Australia’s Great Barrier Reef, we find that split spawning increased the ersity of sources and reliability of larval supply the reefs could receive, especially in regions with low and intrinsically variable connectivity. Such increased larval supply might help counteract the expected declines in reproductive success associated with split spawning events.
Publisher: Springer Science and Business Media LLC
Date: 13-12-2006
DOI: 10.1007/S10803-006-0324-6
Abstract: Hyperserotonemia is the most consistent serotonin-related finding in autism. The basis of this phenomenon, and its relationship to the central serotonergic dysfunction remains unclear. Platelet serotonin level (PSL) in 53 autistic adults and 45 healthy controls was measured. Mean PSL in autistic group (75.7 +/- 37.4 ng/microL) was significantly higher than the control s le (59.2 +/- 16.2 ng/microL) due to a presence of hyperserotonemic subjects which comprised 32% of the patients. PSL of autistic subjects did not correlate with the severity of symptoms, as measured by total CARS score, or the degree of mental retardation. However, significant negative relationship was observed between PSL and speech development, indicating the relationship between the peripheral 5HT concentrations and verbal abilities in autistic subjects.
Publisher: Brill
Date: 2006
Publisher: Wiley
Date: 02-02-2016
DOI: 10.1111/COBI.12665
Abstract: Controlling the spread of invasive species, pests, and pathogens is often logistically limited to interventions that target specific locations at specific periods. However, in complex, highly connected systems, such as marine environments connected by ocean currents, populations spread dynamically in both space and time via transient connectivity links. This results in nondeterministic future distributions of species in which local populations emerge dynamically and concurrently over a large area. The challenge, therefore, is to choose intervention locations that will maximize the effectiveness of the control efforts. We propose a novel method to manage dynamic species invasions and outbreaks that identifies the intervention locations most likely to curtail population expansion by selectively targeting local populations most likely to expand their future range. Critically, at any point during the development of the invasion or outbreak, the method identifies the local intervention that maximizes the long-term benefit across the ecosystem by restricting species' potential to spread. In so doing, the method adaptively selects the intervention targets under dynamically changing circumstances. To illustrate the effectiveness of the method we applied it to controlling the spread of crown-of-thorns starfish (Acanthaster sp.) outbreaks across Australia's Great Barrier Reef. Application of our method resulted in an 18-fold relative improvement in management outcomes compared with a random targeting of reefs in putative starfish control scenarios. Although we focused on applying the method to reducing the spread of an unwanted species, it can also be used to facilitate the spread of desirable species through connectivity networks. For ex le, the method could be used to select those fragments of habitat most likely to rebuild a population if they were sufficiently well protected.
Publisher: Elsevier BV
Date: 08-2018
Publisher: Springer Science and Business Media LLC
Date: 09-04-2020
Publisher: Informa UK Limited
Date: 03-2007
Publisher: Informa UK Limited
Date: 06-2007
Publisher: Public Library of Science (PLoS)
Date: 23-12-2010
Publisher: EDP Sciences
Date: 2012
DOI: 10.1051/LIMN/2011051
Publisher: Public Library of Science (PLoS)
Date: 22-08-2018
Publisher: Springer Science and Business Media LLC
Date: 06-01-2011
Publisher: Springer Science and Business Media LLC
Date: 02-07-2015
Publisher: Oxford University Press (OUP)
Date: 06-2014
Abstract: Traits that aid in the invasion process should exhibit a gradient across the expansion range in response to changing selection pressures. Aggression has been repeatedly associated with invasion success in many taxa, as it may help invaders to wrestle the resources from other species which enhances their success in a novel environment. However, aggression primarily allows in iduals to overcome conspecific rivals, providing advantages in competition over resources. Agonistic prowess could therefore increase fitness at both ends of the expansion gradient. Here we review the role of aggression in range expansion of invasive species, and its potential role as a driver of range expansion. We analyze how these different mechanisms could affect trait variation in expanding and invasive populations. Specifically, we look at how aggression could help dilate the edges of a population through niche competition, as well as lead to exclusion from the center (i.e. areas of high population density) by the conspe-cifics. Both of these processes will result in a characteristic spatial distribution of phenotypes related to aggression that could provide insights into the ecological pressures and dynamics of expanding populations, potentially providing clues to their success as niche competitors and invasive species.
Publisher: Elsevier BV
Date: 03-2010
DOI: 10.1016/J.IJPHARM.2009.12.015
Abstract: Protein stabilization by solvent additives is frequently used concept in formulation development, although new technologies implemented over the past decade can improve protein biophysical as well as clinical properties by protein structural design (e.g. PEGylation, acylation, hesylation). The scope of this work was to evaluate the effect of chosen carbohydrate or polyol stabilizer in the formulation firstly on linear peptide sequences on instable model of rHuG-CSF cleaved macromolecule by novel method named protein and peptide stabilizer pre-screening PPSP (formulated tryptic digest mixture stability evaluation in 54 h) and on overall stability of rHuG-CSF macromolecule by quantifying all relevant degradation parameters. Comprehensive protein stabilizing screening study included conformational analysis of formulated rHuG-CSF protein to obtain information on its secondary structure conformational stability. Protein aggregation induced by modulating conditions in solution (e.g. thermal stress and agitation) was monitored over discrete time periods. Oxidation and deamidation, as well as truncation or hydrolysis were accurately quantified. Together with pre-screening data, obtained by fast and resourceful amino acid sequence degradation analysis by LC-MS, statistical data evaluation of stabilizing contribution of substances selected from group of carbohydrates and polyols was performed. According to the statistical interpretation of obtained results the stabilizers were ranked in the following order: turanose, D-trehalose, lactitol, acetate buffer (non-stabilized s le), xylitol, cellobiitol, sorbitol, D-lyxose, leucrose, sorbitol without polysorbate, cellobiose.
Publisher: Springer Berlin Heidelberg
Date: 15-11-2011
Publisher: Brill
Date: 2009
Publisher: Elsevier BV
Date: 12-2012
Publisher: Elsevier BV
Date: 2017
Publisher: IMR Press
Date: 2010
DOI: 10.2741/3606
Abstract: Although functional genomics methods offer new viewpoint on molecular processes involved in particular pathological state, these methods, in particular proteomics, are still under-represented in Dupuytren's contracture research. However, several recent papers based on functional genomics technologies represent a breakthrough in studying Dupuytren's contracture as they revealed new molecular players that had been impossible to detect by traditional molecular biology methods. Using computational tools to provide biological context for such broad arrays of data accelerates the process of homing in on the potential molecular markers and drug targets. Interactomes, maps of protein-protein interactions characteristic for the disease and as such putative models of its molecular pathology, are especially useful for this purpose, facilitating the transition from global screening methods to specific experiments aimed at therapy development. The combination of these approaches in Dupuytren's contracture research might therefore facilitate the discovery of novel therapeutic targets and diagnostic markers indicative of disease progression.
Publisher: Elsevier BV
Date: 09-2009
DOI: 10.1016/J.BIOPHA.2008.10.005
Abstract: Dupuytren's disease (DD) is a fibroproliferative disorder, the cure for which is still limited to surgical excision of the affected fascia, often leading to high recurrence rates. Due to this fact, non-surgical treatments are being investigated, among them those targeting molecular processes of proliferation and differentiation in Dupuytren's cell cultures. Drugs with antiproliferative action may be valuable in DD treatment. Through characterization of changes on DD-specific cells, we, therefore, decided to test the therapeutic potential of new cytostatic drugs for DD treatment and/or for reduction of post-operative recurrence rates. The N-sulfonylpyrimidine derivative, amidino-substituted benzimidazo[1,2-a]quinoline, and amidino dihydrothienothienyl[2,3-c]quinolone hydrochloride, known to affect proliferation processes, were tested for their antiproliferative activity on primary fibroblasts/myofibroblasts cell cultures derived from the palmar fascia of patients with DD. Only amidino dihydrothienothienyl[2,3-c]quinolone hydrochloride acted in a highly specific manner on cells derived from diseased fascia of DD patients and exhibited a low cytotoxic effect. This result might be a consequence of its specific activity on cytoskeleton changes occurring in differentiating cells. A similar short-term differential antiproliferative effect was observed by the N-sulfonylpyrimidine derivative that was, however, completely lost after 6- and 14-day treatments. The amidino-substituted benzimidazo[1,2-a]quinoline exerted a strong non-specific, dose-related antiproliferative activity on cell types.
Publisher: Wiley
Date: 14-04-2013
DOI: 10.1002/RCM.6528
Abstract: We describe a novel negative chemically activated fragmentation ositive chemically activated fragmentation (CAF-/CAF+) technique for protein identification. The technique was used to investigate Lactobacillus brevis adaptation to nutrient deprivation. The CAF-/CAF+ method enables de novo sequencing of derivate peptides with negative and positive ion mode matrix-assisted laser desorption/ionization (MALDI) tandem mass spectrometry (MS/MS). Peptide sequences obtained from MS/MS spectra were matched against the National Center for Biotechnology Information (NCBI) non-redundant (nr) database and confirmed by the mass spectrometry data of elucidated peptide mass sequences derived from the annotated genome. This improved protein identification method highlighted 36 differentially expressed proteins in the proteome of L. brevis after 75 days of starvation. The results revealed the key differences in the metabolic pathways that are responsible for the survival of L. brevis in a hostile environment. Proteomics analysis demonstrated that numerous proteins engaged in glucose and amino-acid catabolizing pathways, glycerolipid metabolizing pathways, and stress-response mechanisms are differentially expressed after long-term starvation. Amino acid and proteomics analysis indicated that starved L. brevis metabolized arginine, glycine, and histidine from dead cells as alternative nutrient sources. The production of lactic acid also varied between the parent cells and the starved cells. Differentially expressed proteins identified exclusively by peptide sequence reading provided promising results for CAF-/CAF+ implementation in a standard proteomics workflow (e.g., biomarker and mutation discovery and biotyping). The practical performance of a reliable de novo sequencing technique in routine proteomics analysis is emphasized in this article.
Publisher: Wiley
Date: 08-08-2014
Publisher: Elsevier BV
Date: 09-2012
DOI: 10.1016/J.BEPROC.2012.05.011
Abstract: Ecosystems today increasingly suffer invasions by multiple invasive species, some of which may share similar advantageous life history traits and ecological niche. In such cases, direct competition can influence invasion success of both species, and provide insights into competition without co-evolution in species equally novel to the environment. We used two widespread crayfish invaders of freshwater ecosystems of Europe, signal crayfish (Pacifastacus leniusculus) and spiny cheek crayfish (Orconectes limosus), to investigate how behavioural decisions in agonistic encounters contribute to competitive advantages in the absence of adaptation to either opponents or an environment. In direct competition against novel but comparable opponents, the key factor for establishing clear dominance of P. leniusculus in interspecific bouts was its greater tendency towards continued engagement in high-intensity fights. With O. limosus in iduals consistently retreating from staged bouts as fights became more intense, P. leniusculus in iduals did not need to adapt their strategy to be successful, suggesting that their agonistic behaviour intrinsically predisposed them to win. While both species are detrimental to invaded ecosystems, our results indicate that aggressive behaviour of P. leniusculus against unfamiliar opponents could allow it to more easily outcompete other comparable species and consequently present a potentially greater threat for native ecosystems.
Publisher: Wiley
Date: 28-12-2021
DOI: 10.1002/ECM.1494
Abstract: Cumulative impacts assessments on marine ecosystems have been hindered by the difficulty of collecting environmental data and identifying drivers of community dynamics beyond local scales. On coral reefs, an additional challenge is to disentangle the relative influence of multiple drivers that operate at different stages of coral ontogeny. We integrated coral life history, population dynamics, and spatially explicit environmental drivers to assess the relative and cumulative impacts of multiple stressors across 2,300 km of the world’s largest coral reef ecosystem, Australia’s Great Barrier Reef (GBR). Using literature data, we characterized relationships between coral life history processes (reproduction, larval dispersal, recruitment, growth, and mortality) and environmental variables. We then simulated coral demographics and stressor impacts at the organism (coral colony) level on ,800 in idual reefs linked by larval connectivity and exposed to temporally and spatially realistic regimes of acute (crown‐of‐thorns starfish outbreaks, cyclones, and mass coral bleaching) and chronic (water‐quality) stressors. Model simulations produced a credible reconstruction of recent (2008–2020) coral trajectories consistent with monitoring observations, while estimating the impacts of each stressor at reef and regional scales. Overall, simulated coral populations declined by one‐third across the GBR, from an average of ~29% to ~19% hard coral cover. By 2020, % of the GBR had coral cover higher than 30%, a status of reef health corroborated by scarce and sparsely distributed monitoring data. Reef‐wide annual rates of coral mortality were driven by bleaching (48%) ahead of cyclones (41%) and starfish predation (11%). Beyond the reconstructed status and trends, the model enabled the emergence of complex interactions that compound the effects of multiple stressors while promoting a mechanistic understanding of coral cover dynamics. Drivers of coral cover growth were identified notably, water quality (suspended sediments) was estimated to delay recovery for at least 25% of inshore reefs. Standardized rates of coral loss and recovery allowed the integration of all cumulative impacts to determine the equilibrium cover for each reef. This metric, combined with maps of impacts, recovery potential, water‐quality thresholds, and reef state metrics, facilitates strategic spatial planning and resilience‐based management across the GBR.
Publisher: Humana Press
Date: 2012
DOI: 10.1007/978-1-61779-965-5_2
Abstract: Research into the molecular mechanism of Dupuytren's disease (DD) illustrates all the problems common to drug discovery in orphan diseases, but also in more commonly investigated ailments. Current findings characterize DD as a disease with complex molecular pathology, with changes in expression of multiple genes and proteins as well as many contributing risk factors. Some of the observed changes include genes and proteins that have been identified in a number of other pathological processes, such as TGF-β, some which may be more specific to DD, such as ADAM12, and undoubtedly also some that have yet to be discovered in future studies. When all these results are taken into consideration, it can be deduced that DD is an end result of several pathological processes that can have many points of origin, and probably involves several subtypes that give rise to sufficiently similar clinical symptoms to be unified under a single medical term. Such breadth of view has become possible with the advent of functional genomics methods and system-wide overview of the molecular processes, which highlight molecular players and processes that might not be intuitively obvious from symptoms, as is the case with the observed parallels with wound-healing processes. As functional genomics methods allow researchers to compile a more complete image of the molecular mechanisms involved in DD pathogenesis, they also help to propose new drug targets that can be employed to develop an effective pharmacological treatment for DD. Identification of key molecular players in DD has already benefited from the integration of functional genomics and biocomputational methods, and such approach may reveal new ways how we can interfere with the emergence of the DD phenotype.
Publisher: Wiley
Date: 13-10-2014
DOI: 10.1111/GCB.12725
Abstract: Under projections of global climate change and other stressors, significant changes in the ecology, structure and function of coral reefs are predicted. Current management strategies tend to look to the past to set goals, focusing on halting declines and restoring baseline conditions. Here, we explore a complementary approach to decision making that is based on the anticipation of future changes in ecosystem state, function and services. Reviewing the existing literature and utilizing a scenario planning approach, we explore how the structure of coral reef communities might change in the future in response to global climate change and overfishing. We incorporate uncertainties in our predictions by considering heterogeneity in reef types in relation to structural complexity and primary productivity. We examine 14 ecosystem services provided by reefs, and rate their sensitivity to a range of future scenarios and management options. Our predictions suggest that the efficacy of management is highly dependent on biophysical characteristics and reef state. Reserves are currently widely used and are predicted to remain effective for reefs with high structural complexity. However, when complexity is lost, maximizing service provision requires a broader portfolio of management approaches, including the provision of artificial complexity, coral restoration, fish aggregation devices and herbivore management. Increased use of such management tools will require capacity building and technique refinement and we therefore conclude that ersification of our management toolbox should be considered urgently to prepare for the challenges of managing reefs into the 21st century.
Publisher: The Royal Society
Date: 04-2015
Abstract: Many biological systems, from fragmented landscapes to host populations, can be represented as networks of connected habitat patches. Links between patches in these connectivity networks can represent equally erse processes, from in iduals moving through the landscape to pathogen transmissions or successive colonization events in metapopulations. Any of these processes can be characterized as stochastic, with functional links among patches that exist with various levels of certainty. This stochasticity then needs to be reflected in the algorithms that aim to predict the dispersal routes in these networks. Here we adapt the concept of reliability to characterize the likelihood that a specific path will be used for dispersal in a probabilistic connectivity network. The most reliable of the paths that connect two patches will then identify the most likely sequence of intermediate steps between these patches. Path reliability will be sensitive to targeted disruptions of in idual links that form the path, and this can then be used to plan the interventions aimed at either preserving or disrupting the dispersal along that path. The proposed approach is general, and can be used to identify the most likely dispersal routes in various contexts, such as predicting patterns of migrations, colonizations, invasions and epidemics.
Publisher: Public Library of Science (PLoS)
Date: 28-11-2017
Publisher: Wiley
Date: 17-07-2019
DOI: 10.1111/DDI.12969
Publisher: Elsevier BV
Date: 12-2021
DOI: 10.1016/J.CUB.2021.09.078
Abstract: Climate change and ENSO have triggered five mass coral bleaching events on Australia's Great Barrier Reef (GBR), three of which occurred in the last 5 years.
Publisher: Cold Spring Harbor Laboratory
Date: 02-12-2020
DOI: 10.1101/2020.12.01.406413
Abstract: Cumulative impacts assessments on marine ecosystems have been hindered by the difficulty of collecting environmental data and identifying drivers of community dynamics beyond local scales. On coral reefs, an additional challenge is to disentangle the relative influence of multiple drivers that operate at different stages of coral ontogeny. We integrated coral life history, population dynamics and spatially-explicit environmental drivers to assess the relative and cumulative impacts of multiple stressors across 2,300 km of the world’s largest coral reef ecosystem, Australia’s Great Barrier Reef (GBR). Using literature data, we characterized relationships between coral life history processes (reproduction, larval dispersal, recruitment, growth and mortality) and environmental variables. We then simulated coral demographics and stressor impacts at the organism (coral colony) level on ,800 in idual reefs linked by larval connectivity, and exposed to temporally- and spatially-realistic regimes of acute (crown-of-thorns starfish outbreaks, cyclones and mass coral bleaching) and chronic (water quality) stressors. Model simulations produced a credible reconstruction of recent (2008–2020) coral trajectories consistent with monitoring observations, while estimating the impacts of each stressor at reef and regional scales. Overall, corals declined by one third across the GBR, from an average ∼29% to ∼19% hard coral cover. By 2020, less than 20% of the GBR had coral cover higher than 30%. Global annual rates of coral mortality were driven by bleaching (48%) ahead of cyclones (41%) and starfish predation (11%). Beyond the reconstructed status and trends, the model enabled the emergence of complex interactions that compound the effects of multiple stressors while promoting a mechanistic understanding of coral cover dynamics. Drivers of coral cover growth were identified notably, water quality (suspended sediments) was estimated to delay recovery for at least 25% of inshore reefs. Standardized rates of coral loss and recovery allowed the integration of all cumulative impacts to determine the equilibrium cover for each reef. This metric, combined with maps of impacts, recovery potential, water quality thresholds and reef state metrics, facilitates strategic spatial planning and resilience-based management across the GBR.
Publisher: Wiley
Date: 07-09-2018
DOI: 10.1111/COBI.13161
Abstract: The decline of coral cover on Australia's Great Barrier Reef (GBR) has largely been attributed to the cumulative pressures of tropical cyclones, temperature-induced coral bleaching, and predation by crown-of-thorns starfish (CoTS). In such a complex system, the effectiveness of any management intervention will become apparent only over decadal time scales. Systems modeling approaches are therefore essential to formulating and testing alternative management strategies. For a network of reefs, we developed a metacommunity model that incorporated the cumulative pressures of tropical cyclones, coral bleaching, predation, and competition between corals. We then tested the response of coral cover to management interventions including catchment restoration to reduce discharge onto the reef during cyclone-induced flood events and enhanced protection of trophic networks supporting predation of CoTS. Model results showed good agreement with long-term monitoring of the GBR, including cyclical outbreaks of CoTS driven by predator-prey dynamics on the network of reefs. Testing of intervention strategies showed that catchment restoration would likely improve coral cover. However, strategies that combined catchment restoration with enhanced CoTS predation were far more effective than catchment restoration alone.
Publisher: Informa UK Limited
Date: 07-2011
Publisher: Wiley
Date: 16-12-2008
DOI: 10.1002/PATH.2483
Abstract: Dupuytren's disease (DD) is a fibromatosis characterized by non-malignant transformation of palmar fascia leading to permanent contraction of one or more fingers. Despite the extensive knowledge of its clinical pathogenesis, the aetiology of this disease remains obscure. In the present paper, we report for the first time on the proteomic profiling of diseased versus unaffected patient-matched palmar fasciae tissues from DD patients using two-dimensional gel electrophoresis coupled with mass spectrometry analysis. The herein identified proteins were then used to create the protein-protein interaction network (interactome). Such an integrated approach revealed the involvement of several different molecular processes related to DD progression, including extra- and intra-cellular signalling, oxidative stress, cytoskeletal changes, and alterations in cellular metabolism. In particular, autocrine regulation through ERBB-2 and IGF-1R receptors and the Akt signalling pathway have emerged as novel components of pro-survival signalling in Dupuytren's fibroblasts and thus might provide a basis for a new therapeutic strategy in Dupuytren's disease.
Publisher: Wiley
Date: 10-04-2008
DOI: 10.1111/J.1747-0285.2008.00660.X
Abstract: The novel hydroxyurea derivatives of l- and d-amino acid amides 5a-l were prepared by aminolysis of N-(1-benzotriazolecarbonyl)-amino acid amides 4a-f with O-benzylhydroxylamine and N-methylhydroxylamine and evaluated for their antiviral and cytostatic activity against malignant tumor cell lines and normal human fibroblasts. Compounds 5a, 5c, 5e and 5k showed the highest antiproliferative effects against all tumor cell lines tested. The strongest non-specific cytostatic activities against HeLa cells were affected by compounds 5a, 5c, 5e and 5k on MCF-7 cells by 5c, 5e and 5k and MIA PACa-2 cells by 5c and 5k. Differential effects at micromolar concentrations were observed for compounds 5a, 5c, 5e, 5k and 5l in Hep G2 cells, for compounds 5c, 5e, 5k and 5l in PC-3 cells and for compounds 5e, 5k and 5l in SW 620 cells.
Publisher: Finnish Zoological and Botanical Publishing Board
Date: 12-2011
DOI: 10.5735/086.048.0604
No related grants have been discovered for Karlo Hock.