23 research outputs found
Amphidromy Links a Newly Documented Fish Community of Continental Australian Streams, to Oceanic Islands of the West Pacific
BACKGROUND: Indo-Pacific high island streams experience extreme hydrological variation, and are characterised by freshwater fish species with an amphidromous life history. Amphidromy is a likely adaptation for colonisation of island streams following stochastic events that lead to local extirpation. In the Wet Tropics of north-eastern Australia, steep coastal mountain streams share similar physical characteristics to island systems. These streams are poorly surveyed, but may provide suitable habitat for amphidromous species. However, due to their ephemeral nature, common non-diadromous freshwater species of continental Australia are unlikely to persist. Consequently, we hypothesise that coastal Wet Tropics streams are faunally more similar, to distant Pacific island communities, than to nearby faunas of large continental rivers. METHODS/PRINCIPAL FINDINGS: Surveys of coastal Wet Tropics streams recorded 26 species, 10 of which are first records for Australia, with three species undescribed. This fish community is unique in an Australian context in that it contains mostly amphidromous species, including sicydiine gobies of the genera Sicyopterus, Sicyopus, Smilosicyopus and Stiphodon. Species presence/absence data of coastal Wet Tropics streams were compared to both Wet Tropics river networks and Pacific island faunas. ANOSIM indicated the fish fauna of north-eastern Australian coastal streams were more similar to distant Pacific islands (R = 0.76), than to nearby continental rivers (R = 0.98). MAIN CONCLUSIONS/SIGNIFICANCE: Coastal Wet Tropics streams are faunally more similar to distant Pacific islands (79% of species shared), than to nearby continental fauna due to two factors. First, coastal Wet Tropics streams lack many non-diadromous freshwater fish which are common in nearby large rivers. Second, many amphidromous species found in coastal Wet Tropics streams and Indo-Pacific islands remain absent from large rivers of the Wet Tropics. The evolutionary and conservation significance of this newly discovered Australian fauna requires clarification in the context of the wider amphidromous fish community of the Pacific
A novel targeted/untargeted GC-Orbitrap metabolomics methodology applied to Candida albicans and Staphylococcus aureus biofilms
Introduction:
Combined infections from Candida albicans and Staphylococcus aureus are a leading cause of death in the developed world. Evidence suggests that Candida enhances the virulence of Staphylococcus—hyphae penetrate through tissue barriers, while S. aureus tightly associates with the hyphae to obtain entry to the host organism. Indeed, in a biofilm state, C. albicans enhances the antimicrobial resistance characteristics of S. aureus. The association of these microorganisms is also associated with significantly increased morbidity and mortality. Due to this tight association we hypothesised that metabolic effects were also in evidence.
Objectives:
To explore the interaction, we used a novel GC-Orbitrap-based mass spectrometer, the Q Exactive GC, which combines the high peak capacity and chromatographic resolution of gas chromatography with the sub-ppm mass accuracy of an Orbitrap system. This allows the capability to leverage the widely available electron ionisation libraries for untargeted applications, along with expanding accurate mass libraries and targeted matches based around authentic standards.
Methods:
Optimised C. albicans and S. aureus mono- and co-cultured biofilms were analysed using the new instrument in addition to the fresh and spent bacterial growth media.
Results:
The targeted analysis experiment was based around 36 sugars and sugar phosphates, 22 amino acids and five organic acids. Untargeted analysis resulted in the detection of 465 features from fresh and spent medium and 405 from biofilm samples. Three significantly changing compounds that matched to high scoring library fragment patterns were chosen for validation.
Conclusion:
Evaluation of the results demonstrates that the Q Exactive GC is suitable for metabolomics analysis using a targeted/untargeted methodology. Many of the results were as expected: e.g. rapid consumption of glucose and fructose from the medium regardless of the cell type. Modulation of sugar-phosphate levels also suggest that the pentose phosphate pathway could be enhanced in the cells from co-cultured biofilms. Untargeted metabolomics results suggested significant production of cell-wall biosynthesis components and the consumption of non-proteinaceous amino-acids
A qualitative study of community pharmacists’ clinical decision-making skills.
In recent years, self-care has been in the forefront of UK health policy [1], with community pharmacies being promoted as a first point of contact for patients [2], when seeking advice for the treatment of a variety of conditions and minor ailments. As more medicines have become available without prescription this has led to community pharmacists dealing with a wider range of presenting problems and spending more time on making clinical decisions.
Aims / objectives
The area of how community pharmacists make a clinical diagnosis is under-researched. The aim of this exploratory study was to gain an initial insight on how community pharmacists make clinical decisions in order to reach a diagnosis.
Method
A qualitative methodology was employed where semi-structured, face-to-face interviews were conducted with community pharmacists that had been practicing for at least six months at the time of the interviews and did not hold, or were working towards, a prescribing qualification. Pharmacists were identified through snow balling sampling and consent sheets sent to their pharmacies’ registered address. Pharmacists who returned completed consent forms were recruited to the study. All interviews were audio recorded and transcribed ad verbatim. Interviews were analysed, with a team-based approach, using a clinical reasoning based framework analysis to identify themes and subthemes. Ethical approval was granted by the ethics committee at the University of Wolverhampton.
Results
Eight interviews were conducted across England, with five male and three female pharmacists, who had been practicing for periods ranging from one to forty years. The major theme that emerged from the analysis was the poor diagnostic knowledge and ability of the pharmacists and a non-evidence based approach to decision-making. Pharmacists constantly used and overly relied on mnemonic methods both for diagnostic purposes and product selection. Their motives within consultations appeared to be establishing an appropriate product to recommend, rather than the need to establish a diagnosis, and the inability to differentiate between the two processes. However, they did have a sense of the limitations of the methods they used and an awareness for the need to ‘delve deeper’ during consultations but could not articulate how or why this was the case. Themes and sub-themes are explained using confirmatory quotes from the data.
Discussion or Conclusion
The findings of this study suggest that even though community pharmacists are tasked with advising symptom-presenting patients, their poor clinical reasoning skills are preventing them from reaching appropriate diagnoses. In order for community pharmacists to better perform this role, greater emphasis should be given in teaching and practicing clinical reasoning skills during their studies and through continuous professional development. The study is limited by its small sample size.
1. Department of Health. The NHS Plan. A Plan for Investment, A Plan for Reform [Internet]. London: National Health Service; 2000 [cited 6 October 2012]. Available from: http://webarchive.nationalarchives.gov.uk/+/www.dh.gov.uk/en/publicationsandstatistics/publications/publicationspolicyandguidance/dh_4002960
2. Royal Pharmaceutical Society. Improving Urgent and Emergency care through better use of pharmacists [Internet]; 2014 [cited 5 October 2016]. Available from: http://www.rpharms.com/policy-pdfs/urgent-and-emergency-care.pd
Pasture production and composition response after killing Eucalypt trees with herbicides in central Queensland
Clearing woodlands is practised world-wide to increase crop and livestock production, but can result in unintended consequences including woody regrowth and land degradation. The pasture response of 2 eucalypt woodlands in the central Queensland rangelands to killing trees with herbicides, in the presence or absence of grazing and regular spring burning, was recorded over 7 or 8 years to determine the long-term sustainability of these common practices. Herbage mass and species composition plus tree dynamics were monitored in 2 replicated experiments at each site. For 8 years following herbicide application, killing Eucalyptus populnea F. Muell. (poplar box) trees resulted in a doubling of native pasture herbage mass from that of the pre-existing woodland, with a tree basal area of 8.7 m2 ha-1. Conversely, over 7 years with a similar range of seasons, killing E. melanophloia F. Muell. (silver-leaved ironbark) trees of a similar tree basal area had little impact on herbage mass grown or on pasture composition for the first 4 years before production then increased. Few consistent changes in pasture composition were recorded after killing the trees, although there was an increase in the desirable grasses Dichanthium sericeum (R. Br.) A. Camus (Queensland bluegrass) and Themeda triandra Forssk. (kangaroo grass) when grazed conservatively. Excluding grazing allowed more palatable species of the major grasses to enhance their prominence, but seasonal conditions still had a major influence on their production in particular years. Pasture crown basal area was significantly higher where trees had been killed, especially in the poplar box woodland. Removing tree competition did not have a major effect on pasture composition that was independent of other management impositions or seasons, and it did not result in a rapid increase in herbage mass in both eucalypt communities. The slow pasture response to tree removal at one site indicates that regional models and economic projections relating to tree clearing require community-specific inputs
Grazing pressure impacts on two Aristida/Bothriochloa native pasture communities of central Queensland
Managing native pastures for sustainable and economic production requires a good understanding of grazing effects on pasture dynamics. The Aristida/Bothriochloa pastures of north-eastern Australia are important for cattle production but little data on grazing pressure impacts on pastures are available to guide management decisions of producers, for land management education programs, or for predictive modelling. To address this deficiency, four different continuous grazing intensities were imposed on woodland communities over 7 or 8 years at two sites: a Eucalyptus populnea (poplar box) and a E. melanophloia (silver-leaved ironbark) community. Both sites had replicated paddocks grazed at a low, medium or high grazing pressure by +/- tree killing using herbicide (12 paddocks), and 12 ungrazed (nil grazing pressure) 1-ha plots subjected to the same tree-killing contrasts. Grazed paddock areas were fixed and varied between 3.5 and 21.5 ha. Differential grazing pressures were reset each autumn, by adjusting cattle numbers to consume over the next year the equivalent of 0%, 25%, 50% or 75% of the standing pasture mass available.Pasture grasses suitable as indicators of grazing pressure were identified for both communities. Under low grazing pressure, Themeda triandra (kangaroo grass) was the only desirable grass to show a significant increase in total contribution over time at both sites, although Dichanthium sericeum (Queensland bluegrass) also increased its contribution at the poplar box site. Chloris species increased their contribution as grazing pressure increased. The proportion of less palatable Aristida spp. (wiregrasses) in the pasture was not affected by high grazing pressure, although they increased at low grazing pressure in the poplar box community. There were no consistent changes in native legumes or weedy forb species to any treatment. Increasing grazing pressure had a greater negative effect on pasture mass, ground cover and pasture crown cover area than on changing species composition. Most changes in composition due to grazing pressure were smaller than those associated with variable seasonal rainfall, and were greater in the poplar box community. In above-average rainfall years grazing up to 50% of autumn standing pasture mass had no detrimental effect on composition in treeless poplar box country in the short term. The pastures remained stable or improved in both communities when grazing pressure was set annually to utilise 25% of the standing autumn forage
Grazing pressure impacts on two Aristida/Bothriochloa native pasture communities of central Queensland
Map of the West Pacific freshwater fish communities used in analyses.
<p>Map indicating the Wet Tropics of north-eastern Australia, in relation to Papua New Guinea and West Pacific island groups. Open circles denote regions were freshwater fish communities were included for analyses.</p
Phenogram of West Pacific freshwater fish communities.
<p>Phenogram derived from a Bray-Curtis similarity matrix of presence/absence data of freshwater fish fauna from sub-regions of the West Pacific (Key: <b>PNGR</b>  =  Papua New Guinea rivers, <b>WPIS</b>  =  West Pacific island streams, <b>WTR  = </b> Wet Tropics rivers, <b>WTS</b>  =  Wet Tropics streams, <b>CWTS</b>  =  coastal Wet Tropics streams).</p