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1.
PLoS One ; 18(10): e0286813, 2023.
Article in English | MEDLINE | ID: mdl-37856491

ABSTRACT

Knowledge of the spatial requirements of a species is fundamental to understanding its environmental requirements. However, this can be challenging as the size of a species' home range can be influenced by ecological factors such as diet and size-dependent metabolic demands, as well as factors related to the quality of their habitat such as the density and distribution of resources needed for food and shelter. Until recently, the genus Petauroides was thought to include only a single species with a widespread distribution across eastern Australia. However, a recent study has provided genetic and morphological evidence supporting Petauroides minor as a distinct northern species. Previous studies have focused on the ecology of P. volans, but there has been inadequate research on P. minor. Data on home range and habitat use were obtained for both species using a combination of techniques including GPS collar locations, radiotelemetry, and spotlighting and comparisons were made using consistent methodology. Home range sizes of P. minor (4.79 ha ± 0.97 s.d., KUD .95) were significantly larger than those of P. volans (2.0 ha ± 0.42 s.d., KUD .95). There were no significant differences between male and female home range sizes in either species. Both species showed site-specific preferences for tree species and for larger diameter trees for both forage and shelter. Tree size and biomass/ha were significantly greater in the P. volans study sites than the P. minor study sites and there was a negative correlation between home range size and eucalypt biomass. Larger home range size is likely driven by the substantial differences in biomass between northern (tropical) and southern (temperate) eucalypt-dominated habitats affecting the quality and quantity of resources for food and shelter. Understanding landscape use and habitat requirements within each species of Petauroides can provide important information regarding limiting factors and in directing conservation and management planning.


Subject(s)
Ecosystem , Homing Behavior , Animals , Biomass , Food , Australia , Trees
2.
Br J Clin Pharmacol ; 88(7): 3272-3287, 2022 07.
Article in English | MEDLINE | ID: mdl-35106809

ABSTRACT

There is significant interest in the potential for nebulised unfractionated heparin (UFH), as a novel therapy for patients with COVID-19 induced acute hypoxaemic respiratory failure requiring invasive ventilation. The scientific and biological rationale for nebulised heparin stems from the evidence for extensive activation of coagulation resulting in pulmonary microvascular thrombosis in COVID-19 pneumonia. Nebulised delivery of heparin to the lung may limit alveolar fibrin deposition and thereby limit progression of lung injury. Importantly, laboratory studies show that heparin can directly inactivate the SARS-CoV-2 virus, thereby prevent its entry into and infection of mammalian cells. UFH has additional anti-inflammatory and mucolytic properties that may be useful in this context. METHODS AND INTERVENTION: The Can nebulised HepArin Reduce morTality and time to Extubation in Patients with COVID-19 Requiring invasive ventilation Meta-Trial (CHARTER-MT) is a collaborative prospective individual patient data analysis of on-going randomised controlled clinical trials across several countries in five continents, examining the effects of inhaled heparin in patients with COVID-19 requiring invasive ventilation on various endpoints. Each constituent study will randomise patients with COVID-19 induced respiratory failure requiring invasive ventilation. Patients are randomised to receive nebulised heparin or standard care (open label studies) or placebo (blinded placebo-controlled studies) while under invasive ventilation. Each participating study collect a pre-defined minimum dataset. The primary outcome for the meta-trial is the number of ventilator-free days up to day 28 day, defined as days alive and free from invasive ventilation.


Subject(s)
COVID-19 Drug Treatment , Noninvasive Ventilation , Respiratory Insufficiency , Airway Extubation , Heparin , Humans , Lung , Randomized Controlled Trials as Topic , Respiratory Insufficiency/chemically induced , SARS-CoV-2 , Treatment Outcome
3.
Br J Clin Pharmacol ; 88(6): 2802-2813, 2022 06.
Article in English | MEDLINE | ID: mdl-34984714

ABSTRACT

AIMS: To determine the safety and efficacy-potential of inhaled nebulised unfractionated heparin (UFH) in the treatment of hospitalised patients with COVID-19. METHODS: Retrospective, uncontrolled multicentre single-arm case series of hospitalised patients with laboratory-confirmed COVID-19, treated with inhaled nebulised UFH (5000 IU q8h, 10 000 IU q4h, or 25 000 IU q6h) for 6 ± 3 (mean ± standard deviation) days. Outcomes were activated partial thromboplastin time (APTT) before treatment (baseline) and highest-level during treatment (peak), and adverse events including bleeding. Exploratory efficacy outcomes were oxygenation, assessed by ratio of oxygen saturation to fraction of inspired oxygen (FiO2 ) and FiO2 , and the World Health Organisation modified ordinal clinical scale. RESULTS: There were 98 patients included. In patients on stable prophylactic or therapeutic systemic anticoagulant therapy but not receiving therapeutic UFH infusion, APTT levels increased from baseline of 34 ± 10 seconds to a peak of 38 ± 11 seconds (P < .0001). In 3 patients on therapeutic UFH infusion, APTT levels did not significantly increase from baseline of 72 ± 20 to a peak of 84 ± 28 seconds (P = .17). Two patients had serious adverse events: bleeding gastric ulcer requiring transfusion and thigh haematoma; both were on therapeutic anticoagulation. Minor bleeding occurred in 16 patients, 13 of whom were on therapeutic anticoagulation. The oxygen saturation/FiO2 ratio and the FiO2 worsened before and improved after commencement of inhaled UFH (change in slope, P < .001). CONCLUSION: Inhaled nebulised UFH in hospitalised patients with COVID-19 was safe. Although statistically significant, inhaled nebulised UFH did not produce a clinically relevant increase in APTT (peak values in the normal range). Urgent randomised evaluation of nebulised UFH in patients with COVID-19 is warranted and several studies are currently underway.


Subject(s)
COVID-19 Drug Treatment , Heparin , Anticoagulants , Hemorrhage/chemically induced , Hemorrhage/drug therapy , Heparin/adverse effects , Humans , Partial Thromboplastin Time , Retrospective Studies
5.
J Nurs Meas ; 29(1): E18-E38, 2021 04 01.
Article in English | MEDLINE | ID: mdl-33593987

ABSTRACT

BACKGROUND AND PURPOSE: There are a lack of documentation on psychometric assessments on the Malay version of 14-item Resilience scale (RS-14) in Malaysia. This study was to empirically assess its reliability and validity. METHOD: A prospective test-retest design was employed on Malaysian women with early breast cancer (N = 105). Data were analyzed using SPSS version 24. RESULTS: The results showed overall Cronbach alpha values were .92 and .93 for test-retest, respectively. Intraclass correlation coefficient (ICC) values ranged between .62 and .75. This study accepted three factors and two factors for test-retest, respectively. Individual factors showed Cronbach alpha average ranged from .71 to .91. CONCLUSION: The Malay version RS-14 tool was found to be statistically valid, reliable, and reproducible. It was able to measure resilience level in those women under study.


Subject(s)
Breast Neoplasms/psychology , Psychometrics/standards , Resilience, Psychological , Surveys and Questionnaires/standards , Adult , Aged , Aged, 80 and over , Female , Humans , Malaysia , Middle Aged , Prospective Studies , Psychometrics/statistics & numerical data , Reproducibility of Results , Surveys and Questionnaires/statistics & numerical data , Translations
6.
Br J Clin Pharmacol ; 87(8): 3075-3091, 2021 08.
Article in English | MEDLINE | ID: mdl-33377218

ABSTRACT

AIMS: Inhaled nebulised unfractionated heparin (UFH) has a strong scientific and biological rationale that warrants urgent investigation of its therapeutic potential in patients with COVID-19. UFH has antiviral effects and prevents the SARS-CoV-2 virus' entry into mammalian cells. In addition, UFH has significant anti-inflammatory and anticoagulant properties, which limit progression of lung injury and vascular pulmonary thrombosis. METHODS: The INHALEd nebulised unfractionated HEParin for the treatment of hospitalised patients with COVID-19 (INHALE-HEP) metatrial is a prospective individual patient data analysis of on-going randomised controlled trials and early phase studies. Individual studies are being conducted in multiple countries. Participating studies randomise adult patients admitted to the hospital with confirmed SARS-CoV-2 infection, who do not require immediate mechanical ventilation, to inhaled nebulised UFH or standard care. All studies collect a minimum core dataset. The primary outcome for the metatrial is intubation (or death, for patients who died before intubation) at day 28. The secondary outcomes are oxygenation, clinical worsening and mortality, assessed in time-to-event analyses. Individual studies may have additional outcomes. ANALYSIS: We use a Bayesian approach to monitoring, followed by analysing individual patient data, outcomes and adverse events. All analyses will follow the intention-to-treat principle, considering all participants in the treatment group to which they were assigned, except for cases lost to follow-up or withdrawn. TRIAL REGISTRATION, ETHICS AND DISSEMINATION: The metatrial is registered at ClinicalTrials.gov ID NCT04635241. Each contributing study is individually registered and has received approval of the relevant ethics committee or institutional review board. Results of this study will be shared with the World Health Organisation, published in scientific journals and presented at scientific meetings.


Subject(s)
COVID-19 , Heparin , Adult , Bayes Theorem , Humans , Prospective Studies , SARS-CoV-2 , Treatment Outcome
7.
Sci Rep ; 10(1): 19284, 2020 11 06.
Article in English | MEDLINE | ID: mdl-33159131

ABSTRACT

The identification and classification of species are essential for effective conservation management. This year, Australia experienced a bushfire season of unprecedented severity, resulting in widespread habitat loss and mortality. As a result, there has been an increased focus on understanding genetic diversity and structure across the range of individual species to protect resilience in the face of climate change. The greater glider (Petauroides volans) is a large, gliding eucalypt folivore. This nocturnal arboreal marsupial has a wide distribution across eastern Australia and is considered the sole extant member of the genus Petauroides. Differences in morphology have led to suggestions that the one accepted species is actually three. This would have substantial impacts on conservation management, particularly given a recent history of declining populations, coupled with extensive wildfires. Until now, genetic evidence to support multiple species has been lacking. For the first time, we used DArT sequencing on greater glider tissue samples from multiple regions and found evidence of three operational taxonomic units (OTUs) representing northern, central and southern groups. The three OTUs were also supported by our morphological data. These findings have important implications for greater glider management and highlight the role of genetics in helping to assess conservation status.


Subject(s)
Ecosystem , Genetic Variation , Marsupialia/genetics , Animals , Australia , Species Specificity
8.
New Phytol ; 224(4): 1504-1511, 2019 12.
Article in English | MEDLINE | ID: mdl-31419324

ABSTRACT

The significance of shoot surface water uptake (SSWU) has been debated, and it would depend on the range of conditions under which it occurs. We hypothesized that the decline of leaf hydraulic conductance (Kleaf ) in response to dehydration may be recovered through SSWU, and that the hydraulic conductance to SSWU (Ksurf ) declines with dehydration. We quantified effects of leaf dehydration on Ksurf and effects of SSWU on recovery of Kleaf in dehydrated leaves of Avicennia marina. SSWU led to overnight recovery of Kleaf , with recovery retracing the same path as loss of Kleaf in response to dehydration. SSWU declined with dehydration. By contrast, Ksurf declined with rehydration time but not with dehydration. Our results showed a role of SSWU in the recovery of leaf hydraulic conductance and revealed that SSWU is sensitive to leaf hydration status. The prevalence of SSWU in vegetation suggests an important role for atmospheric water sources in maintenance of leaf hydraulic function, with implications for plant responses to changing environments.


Subject(s)
Avicennia/physiology , Plant Leaves/physiology , Plant Shoots/physiology , Dehydration , Kinetics
10.
PLoS One ; 8(1): e54539, 2013.
Article in English | MEDLINE | ID: mdl-23349923

ABSTRACT

Habitat restoration can play an important role in recovering functioning ecosystems and improving biodiversity. Restoration may be particularly important in improving habitat prior to species reintroductions. We reintroduced seven brown treecreeper (Climacteris picumnus) social groups into two nature reserves in the Australian Capital Territory in south-eastern Australia. This study provided a unique opportunity to understand the interactions between restoration ecology, behavioural ecology and habitat ecology. We examined how experimental restoration treatments (addition of coarse woody debris, variations in ground vegetation cover and nest box installation) influenced the behaviour and microhabitat use of radio-tracked individuals to evaluate the success of restoration treatments. The addition of coarse woody debris benefited the brown treecreeper through increasing the probability of foraging on a log or on the ground. This demonstrated the value of using behaviour as a bio-indicator for restoration success. Based on previous research, we predicted that variations in levels of ground vegetation cover would influence behaviour and substrate use, particularly that brown treecreepers would choose sites with sparse ground cover because this allows better access to food and better vigilance for predators. However, there was little effect of this treatment, which was likely influenced by the limited overall use of the ground layer. There was also little effect of nest boxes on behaviour or substrate use. These results somewhat confound our understanding of the species based on research from extant populations. Our results also have a significant impact regarding using existing knowledge on a species to inform how it will respond to reintroduction and habitat restoration. This study also places great emphasis on the value of applying an experimental framework to ecological restoration, particularly when reintroductions produce unexpected outcomes.


Subject(s)
Behavior, Animal/physiology , Conservation of Natural Resources , Passeriformes/physiology , Animals , Biodiversity , Ecology , Ecosystem , Humans , Male , South Australia , Trees
11.
PLoS One ; 7(12): e50612, 2012.
Article in English | MEDLINE | ID: mdl-23227192

ABSTRACT

It is essential to choose suitable habitat when reintroducing a species into its former range. Habitat quality may influence an individual's dispersal decisions and also ultimately where they choose to settle. We examined whether variation in habitat quality (quantified by the level of ground vegetation cover and the installation of nest boxes) influenced the movement, habitat choice and survival of a reintroduced bird species. We experimentally reintroduced seven social groups (43 individuals) of the brown treecreeper (Climacteris picumnus) into two nature reserves in south-eastern Australia. We radio-tracked 18 brown treecreepers from release in November 2009 until February 2010. We observed extensive movements by individuals irrespective of the release environment or an individual's gender. This indicated that individuals were capable of dispersing and actively selecting optimum habitat. This may alleviate pressure on wildlife planners to accurately select the most optimum release sites, so long as the species' requirements are met. There was significant variation in movement between social groups, suggesting that social factors may be a more important influence on movement than habitat characteristics. We found a significant effect of ground vegetation cover on the likelihood of settlement by social groups, with high rates of settlement and survival in dry forests, rather than woodland (where the species typically resides), which has implications for the success of woodland restoration. However, overall the effects of variation in habitat quality were not as strong as we had expected, and resulted in some unpredicted effects such as low survival and settlement in woodland areas with medium levels of ground vegetation cover. The extensive movement by individuals and unforeseen effects of habitat characteristics make it difficult to predict the outcome of reintroductions, the movement behaviour and habitat selection of reintroduced individuals, particularly when based on current knowledge of a species' ecology.


Subject(s)
Birds/physiology , Ecosystem , Trees , Animals , Australian Capital Territory , Conservation of Natural Resources , Telemetry
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