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1.
Emerg Infect Dis ; 28(9): 1785-1795, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35997313

RESUMO

We investigated invasive group A Streptococcus epidemiology in Idaho, USA, during 2008-2019 using surveillance data, medical record review, and emm (M protein gene) typing results. Incidence increased from 1.04 to 4.76 cases/100,000 persons during 2008-2019. emm 1, 12, 28, 11, and 4 were the most common types, and 2 outbreaks were identified. We examined changes in distribution of clinical syndrome, patient demographics, and risk factors by comparing 2008-2013 baseline with 2014-2019 data. Incidence was higher among all age groups during 2014-2019. Streptococcal toxic shock syndrome increased from 0% to 6.4% of cases (p = 0.02). We identified no differences in distribution of demographic or risk factors between periods. Results indicated that invasive group A Streptococcus is increasing among the general population of Idaho. Ongoing surveillance of state-level invasive group A Streptococcus cases could help identify outbreaks, track regional trends in incidence, and monitor circulating emm types.


Assuntos
Choque Séptico , Infecções Estreptocócicas , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Humanos , Idaho/epidemiologia , Incidência , Choque Séptico/epidemiologia , Infecções Estreptocócicas/epidemiologia , Streptococcus pyogenes/genética
2.
Issues Ment Health Nurs ; 43(1): 42-50, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34403302

RESUMO

This paper describes the development and implementation of a peer-support program Always There in a large public mental health service in Queensland, Australia. The program is modelled on Scott's three tier model of peer support, with trained responders providing emotional support to staff following a traumatic adverse event, or when experiencing acute or cumulative stress. Support is provided in complete confidentiality. Main lessons learned in the 2 years since the launch of the program are shared in this paper, outlining successes such as improvements in staff's perception of organisational culture, and challenges related to embedding the program to "business as usual".


Assuntos
Aconselhamento , Cultura Organizacional , Austrália , Humanos , Queensland
3.
Br J Psychiatry ; 219(2): 427-436, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33176895

RESUMO

BACKGROUND: The Zero Suicide framework is a system-wide approach to prevent suicides in health services. It has been implemented worldwide but has a poor evidence-base of effectiveness. AIMS: To evaluate the effectiveness of the Zero Suicide framework, implemented in a clinical suicide prevention pathway (SPP) by a large public mental health service in Australia, in reducing repeated suicide attempts after an index attempt. METHOD: A total of 604 persons with 737 suicide attempt presentations were identified between 1 July and 31 December 2017. Relative risk for a subsequent suicide attempt within various time periods was calculated using cross-sectional analysis. Subsequently, a 10-year suicide attempt history (2009-2018) for the cohort was used in time-to-recurrent-event analyses. RESULTS: Placement on the SPP reduced risk for a repeated suicide attempt within 7 days (RR = 0.29; 95% CI 0.11-0.75), 14 days (RR = 0.38; 95% CI 0.18-0.78), 30 days (RR = 0.55; 95% CI 0.33-0.94) and 90 days (RR = 0.62; 95% CI 0.41-0.95). Time-to-recurrent event analysis showed that SPP placement extended time to re-presentation (HR = 0.65; 95% CI 0.57-0.67). A diagnosis of personality disorder (HR = 2.70; 95% CI 2.03-3.58), previous suicide attempt (HR = 1.78; 95% CI 1.46-2.17) and Indigenous status (HR = 1.46; 95% CI 0.98-2.25) increased the hazard for re-presentation, whereas older age decreased it (HR = 0.92; 95% CI 0.86-0.98). The effect of the SPP was similar across all groups, reducing the risk of re-presentation to about 65% of that seen in those not placed on the SPP. CONCLUSIONS: This paper demonstrates a reduction in repeated suicide attempts after an index attempt and a longer time to a subsequent attempt for those receiving multilevel care based on the Zero Suicide framework.


Assuntos
Tentativa de Suicídio , Austrália/epidemiologia , Estudos de Coortes , Estudos Transversais , Humanos , Risco , Tentativa de Suicídio/prevenção & controle , Tentativa de Suicídio/psicologia
4.
Aust N Z J Psychiatry ; 55(3): 241-253, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33198477

RESUMO

OBJECTIVE: The Zero Suicide Framework, a systems approach to suicide prevention within a health service, is being implemented across a number of states in Australia, and internationally, although there is limited published evidence for its effectiveness. This paper aims to provide a description of the implementation process within a large health service in Australia and describes some of the outcomes to date and learnings from this process. METHOD: Gold Coast Mental Health and Specialist Services has undertaken an implementation of the Zero Suicide Framework commencing in late 2015, aiming for high fidelity to the seven key elements. This paper describes the practical steps undertaken by the service, the new practices embedded, emphasis on supporting staff following the principles of restorative just culture and the development of an evaluation framework to support a continuous quality improvement approach. RESULTS: Improvements have been demonstrated in terms of processes implementation, enhanced staff skills and confidence, positive cultural change and innovations in areas such as the use of machine learning for identification of suicide presentations. A change to 'business as usual' has benefited thousands of consumers since the implementation of a Suicide Prevention Pathway in late 2016 and achieved reductions in rates of repeated suicide attempts and deaths by suicide in Gold Coast Mental Health and Specialist Services consumers. CONCLUSION: An all-of-service, systems approach to suicide prevention with a strong focus on cultural shifts and aspirational goals can be successfully implemented within a mental health service with only modest additional resources when supported by engaged leadership across the organisation. A continuous quality improvement approach is vital in the relentless pursuit of zero suicides in healthcare.


Assuntos
Serviços de Saúde Mental , Atenção à Saúde , Humanos , Saúde Mental , Melhoria de Qualidade , Análise de Sistemas
5.
J Public Health Manag Pract ; 27 Suppl 1, COVID-19 and Public Health: Looking Back, Moving Forward: S80-S86, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33239568

RESUMO

Responding to introductions of diseases and conditions of unknown etiology is a critical public health function. In late December 2019, investigation of a cluster of pneumonia cases of unknown origin in Wuhan, China, resulted in the identification of a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Multiple public health surveillance actions were rapidly implemented to detect introduction of the virus into the United States and track its spread including establishment of a national surveillance case definition and addition of the disease, coronavirus disease 2019, to the list of nationally notifiable conditions. Challenges in conducting effective case-based surveillance and the public health data supply chain and infrastructure are discussed.


Assuntos
COVID-19/prevenção & controle , Surtos de Doenças/prevenção & controle , Guias como Assunto , Morbidade , Pandemias/prevenção & controle , Vigilância em Saúde Pública , United States Public Health Service/normas , COVID-19/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Humanos , Pandemias/estatística & dados numéricos , SARS-CoV-2 , Estados Unidos/epidemiologia , United States Public Health Service/estatística & dados numéricos
6.
Australas Psychiatry ; 29(1): 72-74, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33211548

RESUMO

OBJECTIVE: Mental Health Act 2016 (Qld) (MHA 2016) includes many 'less restrictive ways' to minimise involuntary/compulsory treatment. One such measure, the statutory health attorney, has been adopted from the Powers of Attorney Act 1998 (Qld). This paper analyses the statutory health attorney provision against the human rights framework adopted by the United Nations Convention on the Rights of Persons with Disabilities (CRPD). METHOD: The statutory health attorney provision was analysed against the CRPD article 12 (equal recognition before the law). RESULTS: The statutory health attorney provision is not based on the will and preferences of the individual, is not free from conflict of interest and is not subject to the required safeguards. CONCLUSION: The use of a statutory health attorney brings mental health and physical health under the same provision (the fusion law/proposal). However, the statutory health attorney provision is not compatible with the contemporary human rights framework adopted by the CRPD.


Assuntos
Pessoas com Deficiência , Transtornos Mentais , Direitos Humanos , Humanos , Advogados , Transtornos Mentais/terapia , Saúde Mental , Nações Unidas
7.
Australas Psychiatry ; 29(3): 333-336, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33626306

RESUMO

OBJECTIVE: Reductions in suicidal and self-harm presentations to emergency departments (EDs) since COVID-19 indicate changes in help-seeking behaviours, but it is unknown if hospital avoidance equally affects all population groups. METHOD: Socio-demographic and clinical information relating to suicidal and self-harm presentations to EDs in Queensland, Australia, were compared for the period before (March-August 2019) and since the COVID-19 outbreak (March-August 2020). RESULTS: Since COVID, Indigenous Australians and persons with less severe suicidal and self-harm presentations had significantly reduced presentations, while persons younger than 18 years had more presentations. Less suicidal presentations resulted in an admission to inpatient care. CONCLUSIONS: Patterns of reduced attendance to ED in some groups suggest the need for innovative and community-based models of care to help prevent suicides during the pandemic.


Assuntos
COVID-19 , Serviço Hospitalar de Emergência/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Admissão do Paciente/estatística & dados numéricos , Suicídio/estatística & dados numéricos , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Havaiano Nativo ou Outro Ilhéu do Pacífico/etnologia , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Queensland/etnologia , Índice de Gravidade de Doença , Suicídio/etnologia , Adulto Jovem , Prevenção do Suicídio
8.
Proc Biol Sci ; 287(1937): 20202041, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33081615

RESUMO

Biodiversity can affect the properties of groups of organisms, such as ecosystem function and the persistence of colonizing populations. Genomic data offer a newly available window to diversity, complementary to other measures like taxonomic or phenotypic diversity. We tested whether native genetic diversity in field experimental stands of Arabidopsis thaliana affected their aboveground biomass and fecundity in their colonized range. We constructed some stands of genotypes that we a priori predicted would differ in performance or show overyielding. We found no relationship between genetic diversity and stand total biomass. However, increasing stand genetic diversity increased fecundity in high-resource conditions. Polyculture (multiple genotype) stands consistently yielded less biomass than expected based on the yields of component genotypes in monoculture. This under-yielding was strongest in stands with late-flowering and high biomass genotypes, potentially due to interference competition by these genotypes. Using a new implementation of association mapping, we identified genetic loci whose diversity was associated with stand-level yield, revealing a major flowering time locus associated with under-yielding of polycultures. Our field experiment supports community ecology studies that find a range of diversity-function relationships. Nevertheless, our results suggest diversity in colonizing propagule pools can enhance population fitness. Furthermore, interference competition among genotypes differing in flowering time might limit the advantages of polyculture.


Assuntos
Arabidopsis , Biodiversidade , Genótipo , Biomassa , Ecossistema , Genômica
9.
Aust N Z J Psychiatry ; 54(6): 571-581, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32383403

RESUMO

OBJECTIVE: The prevailing paradigm in suicide prevention continues to contribute to the nihilism regarding the ability to prevent suicides in healthcare settings and a sense of blame following adverse incidents. In this paper, these issues are discussed through the lens of clinicians' experiences as second victims following a loss of a consumer to suicide, and the lens of health care organisations. METHOD: We discuss challenges related to the fallacy of risk prediction (erroneous belief that risk screening can be used to predict risk or allocate resources), and incident reviews that maintain a retrospective linear focus on errors and are highly influenced by hindsight and outcome biases. RESULTS: An argument that a Restorative Just Culture should be implemented alongside a Zero Suicide Framework is developed. CONCLUSIONS: The current use of algorithms to determine culpability following adverse incidents, and a linear approach to learning ignores the complexity of the healthcare settings and can have devastating effects on staff and the broader healthcare community. These issues represent 'inconvenient truths' that must be identified, reconciled and integrated into our future pathways towards reducing suicides in health care. The introduction of Zero Suicide Framework can support the much-needed transition from relying on a retrospective focus on errors (Safety I) to a more prospective focus which acknowledges the complexities of healthcare (Safety II), when based on the Restorative Just Culture principles. Restorative Just Culture replaces backward-looking accountability with a focus on the hurts, needs and obligations of all who are affected by the event. In this paper, we argue that the implementation of Zero Suicide Framework may be compromised if not supported by a substantial workplace cultural change. The process of responding to critical incidents implemented at the Gold Coast Mental Health and Specialist Services is provided as an example of a successful implementation of Restorative Just Culture-based principles that has achieved a culture change required to support learning, improving and healing for our consumers, their families, our staff and broader communities.


Assuntos
Atenção à Saúde , Prevenção do Suicídio , Humanos , Estudos Prospectivos , Estudos Retrospectivos
10.
Ecol Lett ; 22(1): 45-55, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30450720

RESUMO

Dispersal is a key ecological process that is strongly influenced by both phenotype and environment. Here, we show that juvenile environment influences dispersal not only by shaping individual phenotypes, but also by changing the phenotypes of neighbouring conspecifics, which influence how individuals disperse. We used a model system (Tribolium castaneum, red flour beetles) to test how the past environment of dispersing individuals and their neighbours influences how they disperse in their current environment. We found that individuals dispersed especially far when exposed to a poor environment as adults if their phenotype, or even one-third of their neighbours' phenotypes, were shaped by a poor environment as juveniles. Juvenile environment therefore shapes dispersal both directly, by influencing phenotype, as well as indirectly, by influencing the external social environment. Thus, the juvenile environment of even a minority of individuals in a group can influence the dispersal of the entire group.


Assuntos
Meio Ambiente , Tribolium , Animais , Fenótipo
12.
New Phytol ; 223(4): 2054-2062, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31087648

RESUMO

Explaining variation in life history strategies is an enduring goal of evolutionary biology and ecology. Early theory predicted that for plants, annual and perennial life histories reflect adaptations to environments that experience alternative drought regimens. Nevertheless, empirical support for this hypothesis from comparative analyses remains lacking. Here, we test classic life history theory in Heliophila L. (Brassicaceae), a diverse genus of flowering plants native to Africa, controlling for phylogeny and integrating 34 yr of satellite-based drought detection with 2192 herbaria occurrence records. We find that the common ancestor of these species was likely to be an annual, and that perenniality and annuality have repeatedly evolved, an estimated seven and five times, respectively. By comparing historical drought regimens, we show that annuals rather than perennial species occur in environments where droughts are significantly more frequent. We also find evidence that annual plants adapt to predictable drought regimens by escaping drought-prone seasons as seeds. These results yield compelling support for longstanding theoretical predictions by revealing the importance of drought frequency and predictability to explain plant life history. More broadly, this work highlights scalable approaches, integrating herbaria records and remote sensing to address outstanding questions in evolutionary ecology.


Assuntos
Brassicaceae/crescimento & desenvolvimento , Secas , Modelos Logísticos , Filogenia , Especificidade da Espécie
13.
J Hered ; 109(2): 152-161, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29240932

RESUMO

Wildflower seeds are routinely spread along highways and thoroughfares throughout North America as part of federal beautification policy, but the genetic effect of the introduction of these cultivated populations on wild populations of the same species is unknown. Interbreeding may occur between these seeded and wild populations, resulting in several possible outcomes. Here we sample 187 individuals in 12 matched pairs of neighboring wild and seeded populations of the Texas bluebonnet (Lupinus texensis), a species popular in commercially available wildflower seed mixes used by both the Texas Department of Transportation and the public. We use genotyping by sequencing to identify 11741 genome-wide single nucleotide polymorphisms, as well as a smaller number of SNPs from the chloroplast genome, to analyze population structure and genetic diversity within and between the populations. We find a striking lack of population structure both between wild and seeded populations and amongst wild populations. STRUCTURE analyses indicate that all populations are apparently panmictic. This pattern may be explained by extensive swamping of wild populations by seeded germplasm and increased dispersal of semi-domesticated seed across this species' core native range by humans. We discuss the possible negative and positive ramifications of homogenization on the evolutionary future of this popular wildflower species.


Assuntos
Variação Genética , Lupinus/genética , Cruzamento , Evolução Molecular , Polimorfismo de Nucleotídeo Único , Reprodução , Sementes/genética
14.
J Environ Qual ; 47(5): 1232-1241, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30272772

RESUMO

Stormwater filters are a structural best management practice designed to reduce dissolved P losses from runoff. Various industrial byproducts are suitable for use as P sorbing materials (PSMs) for the treatment of drainage water; P sorption by PSMs varies with material physical and chemical properties. Previously, P removal capacity by PSMs was estimated using chemical extractions. We determined the speciation of P when reacted with various PSMs using X-ray absorption near edge structure (XANES) spectroscopy. Twelve PSMs were reacted with P solution in the laboratory under batch or flow-through conditions. In addition, three slag materials were collected from working stormwater filtration structures. Phosphorus K-edge XANES spectra were collected on each reacted PSM and compared with spectra of 22 known P standards using linear combination fitting in Athena. We found evidence of formation of a variety of Ca-, Al-, and/or Fe-phosphate minerals and sorbed phases on the reacted PSMs, with the exact speciation influenced by the chemical properties of the original unreacted PSMs. We grouped PSMs into three general categories based on the dominant P removal mechanism: (i) Fe- and Al-mediated removal [i.e., adsorption of P to Fe- or Al-(hydro-)oxide minerals and/or precipitation of Fe- or Al-phosphate minerals]; (ii) Ca-mediated removal (i.e., precipitation of Ca-phosphate mineral); and (iii) both mechanisms. We recommend the use of Fe/Al sorbing PSMs for use in stormwater filtration structures where stormwater retention time is limited because reaction of P with Fe or Al generally occurs more quickly than Ca-P precipitation.


Assuntos
Fósforo/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Adsorção , Filtração , Poluição Química da Água/prevenção & controle , Poluição Química da Água/estatística & dados numéricos
15.
Australas Psychiatry ; 26(2): 170-175, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29345154

RESUMO

Objective The aim of the current paper is to analyse time trends of non-fatal suicidal behaviour (NFSB) and its repetition at the Gold Coast in 2005-2015. Methods Data on presentations for NFSB were obtained from the Emergency Department (ED) Information System. Potential cases were identified through keyword searches, which were further scrutinised and coded. Annual person-based age-standardised rates for NFSB were calculated. Chi-square test, Poisson regression and Cox proportional hazards regression were used. RESULTS: There was a significant increase in the age-standardised rates of NFSB for males (incidence Rate Ratio = 1.05; 95% confidence interval (CI): 1.04-1.07) and females (iRR = 1.06; 95% CI: 1.04-1.07). Age-specific rates showed significant increases for all age groups, except 25-34 and 55+ for females. Different types of poisoning were the predominant method of NFSB (poisoning only - 61.7% of episodes), followed by cutting (23%). Within the first year after the index episode, 13.4% of subjects repeated NFSB. Multivariate Cox regression model showed that sex, age and method predicted repetition. CONCLUSION: The increasing trends of NFSB and relatively high repetition rates emphasise the need for preventative actions. Monitoring of NFSB at the ED level should be further extended in Australia.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Tentativa de Suicídio/estatística & dados numéricos , Tentativa de Suicídio/tendências , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Queensland/epidemiologia , Adulto Jovem
16.
J Environ Qual ; 46(6): 1270-1286, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29293841

RESUMO

Phosphorus (P) Index evaluations are critical to advancing nutrient management planning in the United States. However, most assessments until now have focused on the risks of P losses in surface runoff. In artificially drained agroecosystems of the Atlantic Coastal Plain, subsurface flow is the predominant mode of P transport, but its representation in most P Indices is often inadequate. We explored methods to evaluate the subsurface P risk routines of five P Indices from Delaware, Maryland (two), Virginia, and North Carolina using available water quality and soils datasets. Relationships between subsurface P risk scores and published dissolved P loads in leachate (Delaware, Maryland, and North Carolina) and ditch drainage (Maryland) were directionally correct and often statistically significant, yet the brevity of the observation periods (weeks to several years) and the limited number of sampling locations precluded a more robust assessment of each P Index. Given the paucity of measured P loss data, we then showed that soil water extractable P concentrations at depths corresponding with the seasonal high water table (WEP) could serve as a realistic proxy for subsurface P losses in ditch drainage. The associations between WEP and subsurface P risk ratings reasonably mirrored those obtained with sparser water quality data. As such, WEP is seen as a valuable metric that offers interim insight into the directionality of subsurface P risk scores when water quality data are inaccessible. In the long term, improved monitoring and modeling of subsurface P losses clearly should enhance the rigor of future P Index appraisals.


Assuntos
Agricultura , Fósforo/análise , Solo , Delaware , North Carolina , Movimentos da Água
18.
J Neurosci ; 35(49): 16213-20, 2015 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-26658871

RESUMO

Angelman syndrome (AS) is a neurodevelopmental disorder associated with developmental delay, lack of speech, motor dysfunction, and epilepsy. In the majority of the patients, AS is caused by the deletion of small portions of maternal chromosome 15 harboring the UBE3A gene. This results in a lack of expression of the UBE3A gene because the paternal allele is genetically imprinted. The UBE3A gene encodes an enzyme termed ubiquitin ligase E3A (E6-AP) that targets proteins for degradation by the 26S proteasome. Because neurodegenerative disease and other neurodevelopmental disorders have been linked to oxidative stress, we asked whether mitochondrial reactive oxygen species (ROS) played a role in impaired synaptic plasticity and memory deficits exhibited by AS model mice. We discovered that AS mice have increased levels of superoxide in area CA1 of the hippocampus that is reduced by MitoQ 10-methanesuflonate (MitoQ), a mitochondria-specific antioxidant. In addition, we found that MitoQ rescued impairments in hippocampal synaptic plasticity and deficits in contextual fear memory exhibited by AS model mice. Our findings suggest that mitochondria-derived oxidative stress contributes to hippocampal pathophysiology in AS model mice and that targeting mitochondrial ROS pharmacologically could benefit individuals with AS. SIGNIFICANCE STATEMENT: Oxidative stress has been hypothesized to contribute to the pathophysiology of neurodevelopmental disorders, including autism spectrum disorders and Angelman syndrome (AS). Herein, we report that AS model mice exhibit elevated levels of mitochondria-derived reactive oxygen species in pyramidal neurons in hippocampal area CA1. Moreover, we demonstrate that the administration of MitoQ (MitoQ 10-methanesuflonate), a mitochondria-specific antioxidant, to AS model mice normalizes synaptic plasticity and restores memory. Finally, our findings suggest that antioxidants that target the mitochondria could be used therapeutically to ameliorate synaptic and cognitive deficits in individuals with AS.


Assuntos
Síndrome de Angelman/complicações , Hipocampo , Mitocôndrias/metabolismo , Transtornos dos Movimentos/etiologia , Transtornos dos Movimentos/patologia , Superóxidos/metabolismo , Sinapses/fisiologia , Análise de Variância , Animais , Condicionamento Psicológico , Modelos Animais de Doenças , Estimulação Elétrica , Medo , Hipocampo/metabolismo , Hipocampo/patologia , Hipocampo/ultraestrutura , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/fisiologia , Compostos Organofosforados/metabolismo , Ubiquinona/análogos & derivados , Ubiquinona/metabolismo
20.
Mol Ecol ; 24(9): 2226-40, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25439241

RESUMO

Asteraceae, the largest family of flowering plants, has given rise to many notorious invasive species. Using publicly available transcriptome assemblies from 35 Asteraceae, including six major invasive species, we examined evidence for micro- and macro-evolutionary genomic changes associated with invasion. To detect episodes of positive selection repeated across multiple introductions, we conducted comparisons between native and introduced genotypes from six focal species and identified genes with elevated rates of amino acid change (dN/dS). We then looked for evidence of positive selection at a broader phylogenetic scale across all taxa. As invasive species may experience founder events during colonization and spread, we also looked for evidence of increased genetic load in introduced genotypes. We rarely found evidence for parallel changes in orthologous genes in the intraspecific comparisons, but in some cases we identified changes in members of the same gene family. Using among-species comparisons, we detected positive selection in 0.003-0.69% and 2.4-7.8% of the genes using site and stochastic branch-site models, respectively. These genes had diverse putative functions, including defence response, stress response and herbicide resistance, although there was no clear pattern in the GO terms. There was no indication that introduced genotypes have a higher proportion of deleterious alleles than native genotypes in the six focal species, suggesting multiple introductions and admixture mitigated the impact of drift. Our findings provide little evidence for common genomic responses in invasive taxa of the Asteraceae and hence suggest that multiple evolutionary pathways may lead to adaptation during introduction and spread in these species.


Assuntos
Asteraceae/genética , Evolução Biológica , Espécies Introduzidas , Seleção Genética , Alelos , Asteraceae/classificação , Hibridização Genômica Comparativa , Efeito Fundador , Genes de Plantas , Genômica/métodos , Genótipo , Modelos Genéticos , Transcriptoma
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