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1.
Microb Ecol ; 86(4): 3097-3110, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37878053

RESUMEN

Drylands comprise one-third of Earth's terrestrial surface area and support over two billion people. Most drylands are projected to experience altered rainfall regimes, including changes in total amounts and fewer but larger rainfall events interspersed by longer periods without rain. This transition will have ecosystem-wide impacts but the long-term effects on microbial communities remain poorly quantified. We assessed belowground effects of altered rainfall regimes (+ 65% and -65% relative to ambient) at six sites in arid and semi-arid Australia over a period of three years (2016-2019) coinciding with a significant natural drought event (2017-2019). Microbial communities differed significantly among semi-arid and arid sites and across years associated with variation in abiotic factors, such as pH and carbon content, along with rainfall. Rainfall treatments induced shifts in microbial community composition only at a subset of the sites (Milparinka and Quilpie). However, differential abundance analyses revealed that several taxa, including Acidobacteria, TM7, Gemmatimonadates and Chytridiomycota, were more abundant in the wettest year (2016) and that their relative abundance decreased in drier years. By contrast, the relative abundance of oligotrophic taxa such as Actinobacteria, Alpha-proteobacteria, Planctomycetes, and Ascomycota and Basidiomycota, increased during the prolonged drought. Interestingly, fungi were shown to be more sensitive to the prolonged drought and to rainfall treatment than bacteria with Basidiomycota mostly dominant in the reduced rainfall treatment. Moreover, correlation network analyses showed more positive associations among stress-tolerant dominant taxa following the drought (i.e., 2019 compared with 2016). Our result indicates that such stress-tolerant taxa play an important role in how whole communities respond to changes in aridity. Such knowledge provides a better understanding of microbial responses to predicted increases in rainfall variability and the impact on the functioning of semi-arid and arid ecosystems.


Asunto(s)
Quitridiomicetos , Microbiota , Humanos , Ecosistema , Sequías , Microbiología del Suelo , Australia , Suelo/química , Bacterias/genética
2.
Molecules ; 28(14)2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37513272

RESUMEN

This study investigated the effects of a modified rice bran arabinoxylan compound (RBAC) as a dietary supplement on the gut microbiota of healthy adults. Ten volunteers supplemented their diet with 1 g of RBAC for six weeks and 3 g of RBAC for another six weeks, with a three-week washout period. Faecal samples were collected every 3 weeks over 21 weeks. Microbiota from faecal samples were profiled using 16S rRNA sequencing. Assessment of alpha and beta microbiota diversity was performed using the QIIME2 platform. The results revealed that alpha and beta diversity were not associated with the experimental phase, interventional period, RBAC dosage, or time. However, the statistical significance of the participant was detected in alpha (p < 0.002) and beta (weighted unifrac, p = 0.001) diversity. Explanatory factors, including diet and lifestyle, were significantly associated with alpha (p < 0.05) and beta (p < 0.01) diversity. The individual beta diversity of six participants significantly changed (p < 0.05) during the interventional period. Seven participants showed statistically significant taxonomic changes (ANCOM W ≥ 5). These results classified four participants as responders to RBAC supplementation, with a further two participants as likely responders. In conclusion, the gut microbiome is highly individualised and modulated by RBAC as a dietary supplement, dependent on lifestyle and dietary intake.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Oryza , Adulto , Humanos , Oryza/genética , ARN Ribosómico 16S/genética , Suplementos Dietéticos , Heces
3.
Water Res ; 243: 120371, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37506634

RESUMEN

Microbes are sensitive indicators of estuarine processes because they respond rapidly to dynamic disturbance events. As most of the world's population lives in urban areas and climate change-related disturbance events are becoming more frequent, estuaries bounded by cities are experiencing increasing stressors, at the same time that their ecosystem services are required more than ever. Here, using a multidisciplinary approach, we determined the response of planktonic microbial assemblages in response to seasonality and a rainfall disturbance in an urban estuary bounded by Australia's largest city, Sydney. We used molecular barcoding (16S, 18S V4 rRNA) and microscopy-based identification to compare microbial assemblages at locations with differing characteristics and urbanisation histories. Across 142 samples, we identified 8,496 unique free-living bacterial zOTUs, 8,175 unique particle associated bacterial zOTUs, and 1,920 unique microbial eukaryotic zOTUs. Using microscopy, we identified only the top <10% abundant, larger eukaryotic taxa (>10 µm), however quantification was possible. The site with the greater history of anthropogenic impact showed a more even community of associated bacteria and eukaryotes, and a significant increase in dissolved inorganic nitrogen following rainfall, when compared to the more buffered site. This coincided with a reduced proportional abundance of Actinomarina and Synechococcus spp., a change in SAR 11 clades, and an increase in the eukaryotic microbial groups Dinophyceae, Mediophyceae and Bathyoccocaceae, including a temporary dominance of the harmful algal bloom dinoflagellate Prorocentrum cordatum (syn. P. minimum). Finally, a validated hydrodynamic model of the estuary supported these results, showing that the more highly urbanised and upstream location consistently experienced a higher magnitude of salinity reduction in response to rainfall events during the study period. The best abiotic variables to explain community dissimilarities between locations were TDP, PN, modelled temperature and salinity (r = 0.73) for the free living bacteria, TP for the associated bacteria (r = 0.43), and modelled temperature (r = 0.28) for the microbial eukaryotic communities. Overall, these results show that a minor disturbance such as a brief rainfall event can significantly shift the microbial assemblage of an anthropogenically impacted area within an urban estuary to a greater degree than a seasonal change, but may result in a lesser response to the same disturbance at a buffered, more oceanic influenced location. Fine scale research into the factors driving the response of microbial communities in urban estuaries to climate related disturbances will be necessary to understand and implement changes to maintain future estuarine ecosystem services.


Asunto(s)
Diatomeas , Dinoflagelados , Ecosistema , Estuarios , Plancton , Océanos y Mares , Bacterias/genética
4.
Microb Biotechnol ; 15(1): 318-336, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34689422

RESUMEN

Understanding the relative importance of soil microbial diversity, plants and nutrient management is crucial to implement an effective bioremediation approach to xenobiotics-contaminated soils. To date, knowledge on the interactive effects of soil microbiome, plant and nutrient supply on influencing biodegradation potential of soils remains limited. In this study, we evaluated the individual and interactive effects of soil initial bacterial diversity, nutrient amendments (organic and inorganic) and plant presence on the biodegradation rate of pyrene, a polycyclic aromatic hydrocarbon. Initial bacterial diversity had a strong positive impact on soil biodegradation potential, with soil harbouring higher bacterial diversity showing ~ 2 times higher degradation rates than soils with lower bacterial diversity. Both organic and inorganic nutrient amendments consistently improved the degradation rate in lower diversity soils and had negative (inorganic) to neutral (organic) effect in higher diversity soils. Interestingly, plant presence/type did not show any significant effect on the degradation rate in most of the treatments. Structural equation modelling demonstrated that initial bacterial diversity had a prominent role in driving pyrene biodegradation rates. We provide novel evidence that suggests that soil initial microbial diversity, and nutrient amendments should be explicitly considered in the design and employment of bioremediation management strategies for restoring natural habitats disturbed by organic pollutants.


Asunto(s)
Microbiota , Hidrocarburos Policíclicos Aromáticos , Contaminantes del Suelo , Biodegradación Ambiental , Nutrientes , Hidrocarburos Policíclicos Aromáticos/análisis , Suelo , Microbiología del Suelo , Contaminantes del Suelo/análisis , Xenobióticos
5.
New Phytol ; 233(2): 966-982, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34699614

RESUMEN

The pathways regulated in ectomycorrhizal (EcM) plant hosts during the establishment of symbiosis are not as well understood when compared to the functional stages of this mutualistic interaction. Our study used the EcM host Eucalyptus grandis to elucidate symbiosis-regulated pathways across the three phases of this interaction. Using a combination of RNA sequencing and metabolomics we studied both stage-specific and core responses of E. grandis during colonization by Pisolithus microcarpus. Using exogenous manipulation of the abscisic acid (ABA), we studied the role of this pathway during symbiosis establishment. Despite the mutualistic nature of this symbiosis, a large number of disease signalling TIR-NBS-LRR genes were induced. The transcriptional regulation in E. grandis was found to be dynamic across colonization with a small core of genes consistently regulated at all stages. Genes associated to the carotenoid/ABA pathway were found within this core and ABA concentrations increased during fungal integration into the root. Supplementation of ABA led to improved accommodation of P. microcarpus into E. grandis roots. The carotenoid pathway is a core response of an EcM host to its symbiont and highlights the need to understand the role of the stress hormone ABA in controlling host-EcM fungal interactions.


Asunto(s)
Eucalyptus , Micorrizas , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacología , Basidiomycota , Eucalyptus/microbiología , Micorrizas/fisiología , Raíces de Plantas/metabolismo , Simbiosis/fisiología
7.
NPJ Biofilms Microbiomes ; 7(1): 29, 2021 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-33753735

RESUMEN

Diabetic foot infections (DFIs) are a major cause of hospitalization and can lead to lower extremity amputation. In this pilot study, we used a multiomics approach to explore the host-microbe complex within DFIs. We observed minimal differences in the overall microbial composition between PEDIS infection severities, however Staphylococcus aureus and Streptococcus genera were abundant and highly active in most mild to moderate DFIs. Further, we identified the significant enrichment of several virulence factors associated with infection pathogenicity belonging to both Staphylococcus aureus and Streptococcus. In severe DFIs, patients demonstrated a greater microbial diversity and differential gene expression demonstrated the enrichment of multispecies virulence genes suggestive of a complex polymicrobial infection. The host response in patients with severe DFIs was also significantly different as compared to mild to moderate DFIs. This was attributed to the enrichment of host genes associated with inflammation, acute phase response, cell stress and broad immune-related responses, while those associated with wound healing and myogenesis were significantly depleted.


Asunto(s)
Bacterias/clasificación , Coinfección/genética , Pie Diabético/microbiología , Perfilación de la Expresión Génica/métodos , Metagenómica/métodos , Factores de Virulencia/genética , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/patogenicidad , Coinfección/microbiología , Pie Diabético/genética , Femenino , Regulación Bacteriana de la Expresión Génica , Interacciones Huésped-Patógeno , Humanos , Masculino , Desarrollo de Músculos , Filogenia , Proyectos Piloto , Estudios Prospectivos , Análisis de Secuencia de ARN , Índice de Severidad de la Enfermedad , Staphylococcus aureus/clasificación , Staphylococcus aureus/genética , Staphylococcus aureus/aislamiento & purificación , Staphylococcus aureus/patogenicidad , Streptococcus/clasificación , Streptococcus/genética , Streptococcus/aislamiento & purificación , Streptococcus/patogenicidad , Cicatrización de Heridas
8.
Children (Basel) ; 7(12)2020 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-33321773

RESUMEN

Early childhood is important for future cognitive and educational outcomes. Programs overcoming barriers to engagement in early education for Indigenous children must address family cultural needs and target developmental delays. This systematic review identifies culturally adapted programs to improve developmental delays among young children, in response to an identified priority of a remote Indigenous community. Five databases (the Cochrane Library, Embase, Medline, Scopus and CINAHL) were searched for English language papers in January 2018. Study quality was assessed, and findings were analysed thematically. Findings were presented to the community at an event with key stakeholders, to determine their inclusion and face validity. Seven relevant studies, published between 1997 and 2013, were identified by the researchers and each study was supported by the community for inclusion. Three studies included on Native American children and four studies included children from non-Indigenous disadvantaged backgrounds. Findings were reported narratively across four themes: storytelling to improve educational outcomes; family involvement improved development; culturally adapted cognitive behavioural therapy to reduce trauma; rewards-based teaching to improve child attention. Limited published research on culturally adapted and safe interventions for children with developmental delays exists but these four themes from seven studies identify useful components to guide the community and early childhood program development.

10.
Contemp Clin Trials Commun ; 19: 100580, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32548333

RESUMEN

INTRODUCTION: Rice bran arabinoxylan compound (RBAC) is a nutraceutical for enhancing a depleted immune system during and after cancer treatment. This pilot feasibility trial aims to evaluate the effects of RBAC on cancer patients' quality of life during active treatment, compared to placebo, using a validated questionnaire. Other outcome measures include changes in inflammatory and nutritional status, cytokine profile, and gut microbiota. METHODS/DESIGN: The study will recruit 50 participants from a regional cancer center in Australia. Patients aged 18-70, diagnosed with solid organ cancers stage II and above, and currently undergoing active systemic therapies, are eligible. Random allocation of participants into two groups is stratified based on metastatic status and treatment type. The dosage is either 3 g/day of RBAC or placebo in identical packaging. The participants, study coordinator, and treating oncologists are blinded to the interventions. Data collections are at baseline and at four follow-up sessions, which are six weeks apart (24 weeks). Statistical analysis will involve a protected p-value with multiple dependent values and analyzed by ANOVA with repeated measures on the occasion of testing and with both a full Bonferroni or Sidak corrections applied to protect against Type I errors. Any observed significance warrants further analysis with pairwise comparisons. Analysis of covariance will also be performed to assess any influence of the demographic data, cancer diagnosis, as well as changes in physical activity, dietary habits, and complementary medicine usage. Comparisons of gut microbiota will be based on the analysis of the fecal microbiome using 16S ribosomal ribonucleic acid amplicon sequencing. The proposed research timeline is from October 2018 to May 2022. TRIAL REGISTRATION: ANZCTR. Reg No: ACTRN12619000562178p.

11.
Sci Total Environ ; 712: 135994, 2020 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-31931194

RESUMEN

We collected over 40 groundwater samples from a per- and polyfluoroalkyl substances (PFAS) impacted legacy fire fighting training area in Canada to develop an in-depth assessment of the relationship between PFAS and in situ microbial communities. Results suggest differential transport of PFAS of differing chain-length and head group. There is also evidence of PFAS degradation, in particular 6:2 FTS degradation. Although PFAS constituents were not major drivers of microbial community structure, the relative abundance of over one hundred individual genera were significantly associated with PFAS chemistry. For example, lineages within the Oxalobacteraceae family had strong negative correlations with PFAS, whilst the Desulfococcus genus has strong positive correlations. Results also suggest a range of genera may have been stimulated at low to mid-range concentrations (e.g., Gordonia and Acidimicrobium), with some genera potentially inhibited at high PFAS concentrations. Any correlations identified need to be further investigated to determine the underlying reasons for observed associations as this is an open field site with the potential for many confounding factors. Positive correlations may ultimately provide important insights related to development of biodegradation technologies for PFAS impacted sites, while negative correlations further improve our understanding of the potential negative effects of PFAS on ecosystem health.


Asunto(s)
Agua Subterránea , Microbiota , Canadá , Fluorocarburos , Contaminantes Químicos del Agua
12.
Sci Total Environ ; 705: 135806, 2020 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-31838420

RESUMEN

Seagrass biomass represents an important source of organic carbon that can contribute to long-term sediment carbon stocks in coastal ecosystems. There is little empirical data on the long-term microbial decomposition of seagrass detritus, despite this process being one of the key drivers of carbon-cycling in coastal ecosystems, that is, it influences the amount and quality of carbon available for sequestration. Here, our goal was to investigate how litter quality (leaf vs. rhizome/root) and the microbial communities involved in organic matter remineralisation shift over a 2-year field decomposition study north of Sydney, Australia using the temperate seagrass Zostera muelleri. The sites varied in bulk sediment characteristics and the sediment-associated microbial communities, but these variables overall had little influence on long-term seagrass decomposition rates or seagrass-associated microbiomes. The results showed a clear succession of bacterial and archaeal communities for both tissues types from r-strategists such as α- and γ-proteobacteria to K-strategies, including δ-proteobacteria, Bacteroidia and Spirochaetes. We used a new mathematical model to capture how decay rates varied over time and found that two decomposition events occurred for some seagrass leaf samples, possibly due to exudate input from living seagrass roots growing into the litter bag. The new model also indicated that conventional single exponential models overestimate long-term decay rates, and we detected for the first time the refractory, or stable, phase of decomposition for rhizome/root biomass. The stable phase began at approximately 20% mass remaining and after 600 days, and the persistence of rhizome/root biomass was attributed to the anoxic conditions and the preservation of refractory organic matter. While we predict that rhizome/root biomass will contribute more to the long-term sediment carbon stocks, the preservation of leaf carbon may be enhanced at locations were sedimentation is high and burial in anoxic conditions is rapid and constant.


Asunto(s)
Ecosistema , Zosteraceae , Australia , Biomasa , Carbono , Ciclo del Carbono
13.
14.
Cancer Immunol Immunother ; 68(12): 1921-1934, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31637475

RESUMEN

Blockade of the PD-1/PD-L1 pathway with targeted monoclonal antibodies has demonstrated encouraging anti-tumour activity in multiple cancer types. We present the case of a patient with BRAF-negative stage IVC anaplastic thyroid cancer (ATC) treated with the anti-PD-1 monoclonal antibody, pembrolizumab, following radiographic progression on chemoradiation. Blood samples were collected prior to and at four time points during treatment with pembrolizumab. Mass cytometry was used to determine expression of relevant biomarkers by peripheral blood mononuclear cells. Faecal samples were collected at baseline and 4 weeks following treatment initiation; taxonomic profiling using 16S ribosomal RNA (rRNA) gene sequencing was performed. Following treatment, a marked expansion in CD20+ B cell, CD16+ CD56lo NK cell and CD45RO+ CCR7+ central memory CD4+ T-cell populations was observed in the peripheral blood. Proportions of cells expressing the co-receptors TIGIT, OX40 and CD86 also increased during treatment. A high abundance of bacteria of the order Bacteroidales, specifically from the Bacteroidaceae and Rikenellaceae families, was identified in the faecal microbiota. Moreover, the patient's microbiome was enriched in Clostridiales order members Ruminococcaceae, Veillonellaceae and Lachnospiraceae. Alpha diversity of the gut microbiome was significantly higher following initiation of checkpoint therapy as assessed by the Shannon and Simpson index. Our results suggest that treatment with pembrolizumab promotes expansion of T-, B- and NK cell populations in the peripheral blood at the time of tumour regression and have the potential to be implemented as predictive biomarkers in the context of checkpoint blockade therapy. Larger studies to confirm these findings are warranted.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos/uso terapéutico , Linfocitos B/inmunología , Linfocitos T CD4-Positivos/inmunología , Heces/microbiología , Células Asesinas Naturales/inmunología , Carcinoma Anaplásico de Tiroides/tratamiento farmacológico , Neoplasias de la Tiroides/tratamiento farmacológico , Bacteroides , Humanos , Masculino , Microbiota , Persona de Mediana Edad , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , ARN Ribosómico 16S/análisis
15.
Int Wound J ; 16(6): 1477-1486, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31487117

RESUMEN

This study compares two vs six weeks of topical antimicrobial therapy with Cadexomer Iodine in patients with diabetic foot ulcers (DFUs) complicated by chronic biofilm infections. Patients with non-healing DFUs with suspected chronic biofilm infections were eligible for enrolment. Patients were randomised to receive either two or six weeks of treatment with topical Cadexomer Iodine. Tissue biopsies from the ulcers were obtained pre-and-post treatment and underwent DNA sequencing and real-time quantitative polymerase chain reaction (PCR) to determine the total microbial load, community composition, and diversity of bacteria. Scanning electron microscopy confirmed biofilm in all 18 ulcers with suspected chronic biofilm infections. Cadexomer Iodine resulted in 14 of 18 (78%) samples achieving a mean 0.5 log10 reduction in microbial load. Regardless of treatment duration, there was no statistical difference in the reduction of total microbial loads. No difference in the rate of wound healing in the two groups was seen at 6 weeks. Cadexomer Iodine reduces the total microbial load in DFUs with chronic biofilm infections and affects microbial community composition and diversity. All ulcers in both groups showed an initial reduction in wound size with application of Cadexomer Iodine, which might reflect its effect on biofilms.


Asunto(s)
Antiinfecciosos Locales/administración & dosificación , Carga Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Pie Diabético/tratamiento farmacológico , Yodóforos/administración & dosificación , Infección de Heridas/tratamiento farmacológico , Administración Tópica , Bacterias/genética , Bacterias/aislamiento & purificación , Estudios de Cohortes , ADN Bacteriano , Esquema de Medicación , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Microscopía Electrónica de Rastreo , Persona de Mediana Edad , Proyectos Piloto , Cicatrización de Heridas
16.
APMIS ; 127(10): 660-670, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31344275

RESUMEN

Multiple approaches were employed to detect pathogens from bone margins associated with Diabetic Foot Osteomyelitis (DFO). Intra-operative bone specimens of 14 consecutive subjects with suspected DFO were collected over a six-month study period from Liverpool Hospital. Infected bone and a proximal bone margins presumed to be 'clean/non-infected' were collected. Bone material was subjected to conventional culture, DNA sequencing and microscopy. In total, eight of 14 (57%) proximal bone margins had no growth by conventional culture but were identified in all proximal bone specimens by DNA sequencing. Proximal margins had lower median total microbial counts than infected specimens, but these differences were not statistically significant. Pathogens identified by sequencing in infected specimens were identified in proximal margins and the microbiomes were similar (ANOSIM = 0.02, p = 0.59). Using a combination of SEM and/or PNA-FISH, we visualized the presence of microorganisms in infected bone specimens and their corresponding proximal margins of seven patients (50%) with DFO. We identify that bacteria can still reside in what seems to be proximal 'clean' margins. The significance and implications of clinical outcomes requires further analysis from a larger sample size that incorporates differences in surgical and post-operative approaches, correlating any outcomes back to culture-sequence findings.


Asunto(s)
Bacterias/aislamiento & purificación , Técnicas Bacteriológicas/métodos , Huesos/microbiología , Pie Diabético/microbiología , Histocitoquímica/métodos , Metagenómica/métodos , Osteomielitis/microbiología , Bacterias/clasificación , Bacterias/genética , Huesos/cirugía , Pie Diabético/patología , Pie Diabético/cirugía , Humanos , Hibridación Fluorescente in Situ , Microscopía Electrónica de Rastreo , Osteomielitis/patología , Osteomielitis/cirugía , Análisis de Secuencia de ADN
17.
Front Microbiol ; 10: 1011, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31139163

RESUMEN

Seagrasses are globally distributed marine plants that represent an extremely valuable component of coastal ecosystems. Like terrestrial plants, seagrass productivity and health are likely to be strongly governed by the structure and function of the seagrass microbiome, which will be distributed across a number of discrete microenvironments within the plant, including the phyllosphere, the endosphere and the rhizosphere, all different in physical and chemical conditions. Here we examined patterns in the composition of the microbiome of the seagrass Zostera muelleri, within six plant-associated microenvironments sampled across four different coastal locations in New South Wales, Australia. Amplicon sequencing approaches were used to characterize the diversity and composition of bacterial, microalgal, and fungal microbiomes and ultimately identify "core microbiome" members that were conserved across sampling microenvironments. Discrete populations of bacteria, microalgae and fungi were observed within specific seagrass microenvironments, including the leaves and roots and rhizomes, with "core" taxa found to persist within these microenvironments across geographically disparate sampling sites. Bacterial, microalgal and fungal community profiles were most strongly governed by intrinsic features of the different seagrass microenvironments, whereby microscale differences in community composition were greater than the differences observed between sampling regions. However, our results showed differing strengths of microbial preferences at the plant scale, since this microenvironmental variability was more pronounced for bacteria than it was for microalgae and fungi, suggesting more specific interactions between the bacterial consortia and the seagrass host, and potentially implying a highly specialized coupling between seagrass and bacterial metabolism and ecology. Due to their persistence within a given seagrass microenvironment, across geographically discrete sampling locations, we propose that the identified "core" microbiome members likely play key roles in seagrass physiology as well as the ecology and biogeochemistry of seagrass habitats.

18.
PeerJ ; 7: e6534, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30972242

RESUMEN

BACKGROUND: The diet of the koala (Phascolarctos cinereus) is comprised almost exclusively of foliage from the genus Eucalyptus (family Myrtaceae). Eucalyptus produces a wide variety of potentially toxic plant secondary metabolites which have evolved as chemical defences against herbivory. The koala is classified as an obligate dietary specialist, and although dietary specialisation is rare in mammalian herbivores, it has been found elsewhere to promote a highly-conserved but low-diversity gut microbiome. The gut microbes of dietary specialists have been found sometimes to enhance tolerance of dietary PSMs, facilitating competition-free access to food. Although the koala and its gut microbes have evolved together to utilise a low nutrient, potentially toxic diet, their gut microbiome has not previously been assessed in conjunction with diet quality. Thus, linking the two may provide new insights in to the ability of the koala to extract nutrients and detoxify their potentially toxic diet. METHOD: The 16S rRNA gene was used to characterise the composition and diversity of faecal bacterial communities from a wild koala population (n = 32) comprising individuals that predominately eat either one of two different food species, one the strongly preferred and relatively nutritious species Eucalyptus viminalis, the other comprising the less preferred and less digestible species Eucalyptus obliqua. RESULTS: Alpha diversity indices indicated consistently and significantly lower diversity and richness in koalas eating E. viminalis. Assessment of beta diversity using both weighted and unweighted UniFrac matrices indicated that diet was a strong driver of both microbial community structure, and of microbial presence/absence across the combined koala population and when assessed independently. Further, principal coordinates analysis based on both the weighted and unweighted UniFrac matrices for the combined and separated populations, also revealed a separation linked to diet. During our analysis of the OTU tables we also detected a strong association between microbial community composition and host diet. We found that the phyla Bacteroidetes and Firmicutes were co-dominant in all faecal microbiomes, with Cyanobacteria also co-dominant in some individuals; however, the E. viminalis diet produced communities dominated by the genera Parabacteroides and/or Bacteroides, whereas the E. obliqua-associated diets were dominated by unidentified genera from the family Ruminococcaceae. DISCUSSION: We show that diet differences, even those caused by differential consumption of the foliage of two species from the same plant genus, can profoundly affect the gut microbiome of a specialist folivorous mammal, even amongst individuals in the same population. We identify key microbiota associated with each diet type and predict functions within the microbial community based on 80 previously identified Parabacteroides and Ruminococcaceae genomes.

19.
JMIR Res Protoc ; 8(2): e11471, 2019 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-30816848

RESUMEN

BACKGROUND: Primary, specialist, and allied health services can assist in providing equitable access in rural and remote areas, where higher proportions of Aboriginal and Torres Strait Islander people (Aboriginal Australians) reside, to overcome the high rates of chronic diseases experienced by this population group. Little is currently known about the location and frequency of services and the extent to which providers believe delivery is occurring in a sustained and coordinated manner. OBJECTIVE: The objective of this study will be to determine the availability, accessibility, and level of coordination of a range of community-based health care services to Aboriginal people and identify potential barriers in accessing health care services from the perspectives of the health service providers. METHODS: This mixed-methods study will take place in 3 deidentified communities in New South Wales selected for their high population of Aboriginal people and geographical representation of location type (coastal, rural, and border). The study is designed and will be conducted in collaboration with the communities, Aboriginal Community Controlled Health Services (ACCHSs), and other local health services. Data collection will involve face-to-face and telephone interviews with participants who are health and community professionals and stakeholders. Participants will be recruited through snowball sampling and will answer structured, quantitative questions about the availability and accessibility of primary health care, specialist medical and allied health services and qualitative questions about accessing services. Quantitative data analysis will determine the frequency and accessibility of specific services across each community. Thematic and content analysis will identify issues relating to availability, accessibility, and coordination arising from the qualitative data. We will then combine the quantitative and qualitative data using a health ecosystems approach. RESULTS: We identified 28 stakeholder participants across the ACCHSs for recruitment through snowball sampling (coastal, n=4; rural, n=12; and border, n=12) for data collection. The project was funded in 2017, and enrolment was completed in 2017. Data analysis is currently under way, and the first results are expected to be submitted for publication in 2019. CONCLUSIONS: The study will give an indication of the scope and level of coordination of primary, specialist, and allied health services in rural communities with high Aboriginal populations from the perspectives of service providers from those communities. Identification of factors affecting the availability, accessibility, and coordination of services can assist ways of developing and implementing culturally sensitive service delivery. These findings could inform recommendations for the provision of health services for Aboriginal people in rural and remote settings. The study will also contribute to the broader literature of rural and remote health service provision. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/11471.

20.
Aust Health Rev ; 43(3): 314-322, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29335090

RESUMEN

Objective The aim of the present systematic review was to examine the enablers for effective health service delivery for Aboriginal Australians. Methods This systematic review was undertaken in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Papers were included if they had data related to health services for Australian Aboriginal people and were published between 2000 and 2015. The 21 papers that met the inclusion criteria were assessed using the Effective Public Health Practice Project Quality Assessment Tool for Quantitative Studies. Seven papers were subsequently excluded due to weak methodological approaches. Results There were two findings in the present study: (1) that Aboriginal people fare worse than non-Aboriginal people when accessing usual healthcare services; and (2) there are five enablers for effective health care services for Australian Aboriginal people: cultural competence, participation rates, organisational, clinical governance and compliance, and availability of services. Conclusions Health services for Australian Aboriginal people must be tailored and implementation of the five enablers is likely to affect the effectiveness of health services for Aboriginal people. The findings of the present study have significant implications in directing the future design, funding, delivery and evaluation of health care services for Aboriginal Australians. What is known about the topic? There is significant evidence about poor health outcomes and the 10-year gap in life expectancy between Aboriginal and non-Aboriginal people, and limited evidence about improving health service efficacy. What does this paper add? This systematic review found that with usual health care delivery, Aboriginal people experience worse health outcomes. This paper identifies five strategies in the literature that improve the effectiveness of health care services intended for Aboriginal people. What are the implications for practitioners? Aboriginal people fare worse in both experience and outcomes when they access usual care services. Health services intended for Aboriginal people should be tailored using the five enablers to provide timely, culturally safe and high-quality care.


Asunto(s)
Competencia Cultural , Atención a la Salud/organización & administración , Atención a la Salud/estadística & datos numéricos , Accesibilidad a los Servicios de Salud/organización & administración , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Servicios de Salud del Indígena/organización & administración , Servicios de Salud del Indígena/estadística & datos numéricos , Nativos de Hawái y Otras Islas del Pacífico , Australia , Humanos
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