AIM: Our aims were to identify centres of endemism and to infer whether these areas have functioned as refugia for subtropical rain forest plants through historical climate fluctuations. LOCATION: ...Subtropical eastern Australia (23–33° S; 145–155° E). METHODS: We collated 25,000 records of 179 endemic rain forest plants to identify geographical areas with unusually high concentrations of endemic taxa and range‐restricted endemics. We then tested whether centres of endemism coincide with other features indicating refugia, including habitat stability over 120,000 years, and we related dispersal patterns to past habitat stability using seed weight as a surrogate for dispersal ability of endemic plant taxa. RESULTS: We identified five main centres of endemism. Historical stability and other processes affecting diversity, including current rainfall, rain forest area, and topographic complexity, explained 58% of variation in plant‐weighted endemism. Taxa with poor dispersal ability were concentrated in the areas that were most stable historically. MAIN CONCLUSIONS: Several lines of evidence suggest that centres of endemism have functioned as important refugia for subtropical rain forest taxa through historical climate fluctuations. The highest concentrations of range‐restricted endemic species occur in locations that are predicted to have maintained stable rain forest habitat over at least the past 120,000 years. This association was independent from other factors that were expected to promote diversity (i.e. rain forest area and current environmental suitability). These locations have disproportionately high concentrations of species with poor dispersal ability (large‐seeded species).
Australian rainforests have been fragmented due to past climatic changes and more recently landscape change as a result of clearing for agriculture and urban spread. The subtropical rainforests of ...South Eastern Queensland are significantly more fragmented than the tropical World Heritage listed northern rainforests and are subject to much greater human population pressures. The Australian rainforest flora is relatively taxonomically rich at the family level, but less so at the species level. Current methods to assess biodiversity based on species numbers fail to adequately capture this richness at higher taxonomic levels. We developed a DNA barcode library for the SE Queensland rainforest flora to support a methodology for biodiversity assessment that incorporates both taxonomic diversity and phylogenetic relationships. We placed our SE Queensland phylogeny based on a three marker DNA barcode within a larger international rainforest barcode library and used this to calculate phylogenetic diversity (PD). We compared phylo- diversity measures, species composition and richness and ecosystem diversity of the SE Queensland rainforest estate to identify which bio subregions contain the greatest rainforest biodiversity, subregion relationships and their level of protection. We identified areas of highest conservation priority. Diversity was not correlated with rainforest area in SE Queensland subregions but PD was correlated with both the percent of the subregion occupied by rainforest and the diversity of regional ecosystems (RE) present. The patterns of species diversity and phylogenetic diversity suggest a strong influence of historical biogeography. Some subregions contain significantly more PD than expected by chance, consistent with the concept of refugia, while others were significantly phylogenetically clustered, consistent with recent range expansions.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
OBJECTIVES To determine the clinical sensitivity, specificity, negative predictive value, and positive predictive value of a rapid point-of-care diagnostic test to detect elevated matrix ...metalloproteinase 9 levels (InflammaDry). METHODS In a prospective, sequential, masked, multicenter clinical trial, InflammaDry was performed on 206 patients: 143 patients with clinical signs and symptoms of dysfunctional tear syndrome (dry eyes) and 63 healthy individuals serving as controls. Participants were assessed as healthy controls or for a clinical diagnosis of dry eye using the Ocular Surface Disease Index, Schirmer tear test, tear breakup time, and keratoconjunctival staining. MAIN OUTCOME MEASURES The sensitivity and specificity of InflammaDry were compared with clinical assessment. RESULTS InflammaDry showed sensitivity of 85% (in 121 of 143 patients), specificity of 94% (59 of 63), negative predictive value of 73% (59 of 81), and positive predictive value of 97% (121 of 125). CONCLUSION Compared with clinical assessment, InflammaDry is sensitive and specific in diagnosing dry eye. APPLICATION TO CLINICAL PRACTICE Dry eye is often underdiagnosed resulting from poor communication between the clinical assessment of dry eye severity between clinicians and patients. This often leads to a lack of effective treatment. Matrix metalloproteinase 9 is an inflammatory biomarker that has been shown to be elevated in the tears of patients with dry eyes. The ability to accurately detect elevated matrix metalloproteinase 9 levels may lead to earlier diagnosis, more appropriate treatment, and better management of ocular surface disease. Preoperative and perioperative management of inflammation related to dry eyes may reduce dry eyes that develop after laser in situ keratomileusis, improve wound healing, and reduce flap complications. Recognition of inflammation may allow for targeted perioperative therapeutic management of care for patients who undergo cataract and refractive surgery and improve outcomes. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01313351
Previous studies of strategic social interaction in game theory have predominantly used games with clearly-defined turns and limited choices. Yet, most real-world social behaviors involve dynamic, ...coevolving decisions by interacting agents, which poses challenges for creating tractable models of behavior. Here, using a game in which humans competed against both real and artificial opponents, we show that it is possible to quantify the instantaneous dynamic coupling between agents. Adopting a reinforcement learning approach, we use Gaussian Processes to model the policy and value functions of participants as a function of both game state and opponent identity. We found that higher-scoring participants timed their final change in direction to moments when the opponent's counter-strategy was weaker, while lower-scoring participants less precisely timed their final moves. This approach offers a natural set of metrics for facilitating analysis at multiple timescales and suggests new classes of experimental paradigms for assessing behavior.
Globally threatened dry rainforests are poorly studied and conserved when compared to mesic rainforests. Investigations of dry rainforest communities within Australia are no exception. We assessed ...the community diversity, distinctiveness and level of conservation in Central Queensland coastal dry rainforest communities. Our three-marker DNA barcode-based phylogeny, based on rainforest species from the Central Queensland Coast, was combined with the phylogeny from Southeast Queensland. The phylogenetic tree and Central Queensland Coast (CQC) community species lists were used to evaluate phylogenetic diversity (PD) estimates and species composition to pinpoint regions of significant rainforest biodiversity. We evaluated the patterns and relationships between rainforest communities of the biogeographical areas of Central Queensland Coast and Southeast Queensland, and within and between Subregions. Subsequently, we identified areas of the highest distinctiveness and diversity in phylogenetically even rainforest communities, consistent with refugia, and areas significantly more related than random, consistent with expansion into disturbed or harsher areas. We found clear patterns of phylogenetic clustering that suggest that selection pressures for moisture and geology were strong drivers of rainforest distribution and species diversity. These results showed that smaller dry rainforests in Central Queensland Coast (CQC) represented areas of regional plant migration but were inadequately protected. To sustain species diversity and distribution under intense selection pressures of moisture availability and substrate type throughout this dry and geologically complex region, the future conservation of smaller patches is essential.
Australia's Great Sandy Region is of international significance containing two World Heritage areas and patches of rainforest growing on white sand. Previous broad-scale analysis found the Great ...Sandy biogeographic subregion contained a significantly more phylogenetically even subset of species than expected by chance contrasting with rainforest on white sand in Peru. This study aimed to test the patterns of rainforest diversity and relatedness at a finer scale and to investigate why we may find different patterns of phylogenetic evenness compared with rainforests on white sands in other parts of the world. This study focussed on rainforest sites within the Great Sandy and surrounding areas in South East Queensland (SEQ), Australia. We undertook field collections, expanded our three-marker DNA barcode library of SEQ rainforest plants and updated the phylogeny to 95% of the SEQ rainforest flora. We sampled species composition of rainforest in fixed area plots from 100 sites. We calculated phylogenetic diversity (PD) measures as well as species richness (SR) for each rainforest community. These combined with site variables such as geology, were used to evaluate patterns and relatedness. We found that many rainforest communities in the Great Sandy area were significantly phylogenetically even at the individual site level consistent with a broader subregion analysis. Sites from adjacent areas were either not significant or were significantly phylogenetically clustered. Some results in the neighbouring areas were consistent with historic range expansions. In contrast with expectations, sites located on the oldest substrates had significantly lower phylogenetic diversity (PD). Fraser Island was once connected to mainland Australia, our results are consistent with a region geologically old enough to have continuously supported rainforest in refugia. The interface of tropical and temperate floras in part also explains the significant phylogenetic evenness and higher than expected phylogenetic diversity.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Dysfunctional tear syndrome (DTS) is a common and complex condition affecting the ocular surface. The health and normal functioning of the ocular surface is dependent on a stable and sufficient tear ...film. Clinician awareness of conditions affecting the ocular surface has increased in recent years because of expanded research and the publication of diagnosis and treatment guidelines pertaining to disorders resulting in DTS, including the Delphi panel treatment recommendations for DTS (2006), the International Dry Eye Workshop (DEWS) (2007), the Meibomian Gland Dysfunction (MGD) Workshop (2011), and the updated Preferred Practice Pattern guidelines from the American Academy of Ophthalmology pertaining to dry eye and blepharitis (2013). Since the publication of the existing guidelines, new diagnostic techniques and treatment options that provide an opportunity for better management of patients have become available. Clinicians are now able to access a wealth of information that can help them obtain a differential diagnosis and treatment approach for patients presenting with DTS. This review provides a practical and directed approach to the diagnosis and treatment of patients with DTS, emphasizing treatment that is tailored to the specific disease subtype as well as the severity of the condition.
AIM: There is little consensus as to whether stratification of arthropods between canopy and understorey in tropical and subtropical forests is commonplace and if the magnitude of stratification ...changes across different elevations and latitudes. We investigated broad‐scale patterns of vertical stratification of moths collected from extensive cross‐continental fieldwork in a variety of forest types, climates, elevations, latitudes and areas with differing biogeographical history. LOCATION: Tropical and subtropical rain forest in eastern Australia; tropical, subtropical and subalpine forest in Yunnan Province, China; and tropical rain forest in Panama, Vietnam, Brunei and Papua New Guinea. METHODS: Night‐flying moths were trapped from the upper canopy and understorey. We generated a total of 64 data sets to quantify vertical stratification of moths in terms of their species richness, using coverage‐based rarefaction, and assemblage composition, using standardized hierarchical beta diversity. Based on the average temperature lapse rate, we incorporated latitudinal differences into elevation and generated ‘corrected’ elevation for each location, and analysed its relationships with the magnitude of stratification. RESULTS: We found consistent differences between canopy and understorey assemblages at almost all rain forest locations across corrected elevational gradients. The magnitude of vertical stratification in species richness did not change with increasing corrected elevation. In contrast, the difference in assemblage composition increased with increasing corrected elevation in the Northern Hemisphere, while the opposite, albeit weak, trend was found in the Southern Hemisphere. MAIN CONCLUSIONS: Clear vertical stratification was evident in moth assemblages regardless of elevation and latitude. However, the degree to which assemblages are stratified between canopy and understorey is not uniformly related to elevation and latitude. Inconsistencies in the magnitude of vertical stratification between the Northern and Southern Hemisphere, may reflect, on one hand, deep‐time biogeographical differences between the land masses studied and, on the other, place‐to‐place differences in resource availability underpinning the observed moth assemblages.
The chronic inflammatory bowel diseases are characterized by aberrant innate and adaptive immune responses to commensal luminal bacteria. In both human inflammatory bowel disease and in experimental ...models of colitis, there is an increased expression of the enzyme IDO. IDO expression has the capacity to exert antimicrobial effects and dampen adaptive immune responses. In the murine trinitrobenzene sulfonic acid model of colitis, inhibition of this enzyme leads to worsened disease severity, suggesting that IDO acts as a natural break in limiting colitis. In this investigation, we show that induction of IDO-1 by a TLR-9 agonist, immunostimulatory (ISS) DNA, critically contributes to its colitis limiting capacities. ISS DNA induces intestinal expression of IDO-1 but not the recently described paralog enzyme IDO-2. This induction occurred in both epithelial cells and in subsets of CD11c(+) and CD11b(+) cells of the lamina propria, which also increase after ISS-oligodeoxynucleotide. Signaling required for intestinal IDO-1 induction involves IFN-dependent pathways, as IDO-1 was not induced in STAT-1 knockout mice. Using both the trinitrobenzene sulfonic acid and dextran sodium sulfate models of colitis, we show the importance of IDO-1s induction in limiting colitis severity. The clinical parameters and histological correlates of colitis in these models were improved by administration of the TLR-9 agonist; however, when the function of IDO is inhibited, the colitis limiting effects of ISS-oligodeoxynucleotide were abrogated. These findings support the possibility that targeted induction of IDO-1 is an approach deserving further investigation as a therapeutic strategy for diseases of intestinal inflammation.
Background & Aims:
Indoleamine 2,3-dioxygenase (IDO), an interferon γ-induced intracellular enzyme, inhibits lymphocyte proliferation through tryptophan degradation. IDO is highly expressed in the ...mammalian intestine. We sought to determine whether IDO played a regulatory role in the T-cell helper 1 (Th1)-mediated trinitrobenzene sulfonic acid (TNBS) model of colitis.
Methods:
Intrarectal TNBS was given to SJL/J mice along with either placebo or a specific IDO inhibitor. IDO protein and mRNA expression were assessed by Western blotting and real-time PCR. Colonic lamina propria mononuclear cells (LPMNCs) were isolated, fractionated, and cultured, in the presence and absence of IFN-γ, to determine the cell type(s) expressing IDO.
Results:
IDO is expressed by professional antigen-presenting cells in the lamina propria. Induction of TNBS colitis resulted in a significant increase in IDO mRNA (
P = 0.005) and protein expression. IDO inhibition during TNBS colitis resulted in an 80% mortality compared with 10% for placebo-treated animals (
P = 0.0089). IDO inhibition resulted in a more severe colitis both histologically and morphologically (
P < 0.05) and significantly increased colonic proinflammatory cytokine expression compared with placebo-treated animals.
Conclusions:
IDO is expressed in the normal colon and is up-regulated in the setting of TNBS colitis. Inhibition of IDO during TNBS colitis resulted in increased mortality and an augmentation of the normal inflammatory response. These findings suggest that IDO plays an important role in the down-regulation of Th1 responses within the gastrointestinal tract.
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