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1.
Ecol Evol ; 12(7): e9052, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35813908

RESUMO

Widespread plant species are expected to maintain genetic diversity and gene flow via pollen and seed dispersal. Stature is a key life history trait that affects seed and potentially pollen dispersal, with limited stature associated with limited dispersal and greater genetic differentiation. We sampled Hill's tabletop wattle (Acacia hilliana) and curry wattle (Acacia spondylophylla), two co-distributed, widespread, Acacia shrubs of low stature, across the arid Pilbara region of north-western Australia. Using chloroplast sequence and nuclear microsatellite data we evaluated patterns of population genetic and phylogeographic diversity and structure, demographic signals, ratios of pollen to seed dispersal, evidence for historical refugia, and association between elevation and diversity. Results showed strong phylogeographic (chloroplast, G ST = 0.831 and 0.898 for A. hilliana and A. spondylophylla, respectively) and contemporary (nuclear, F ST = 0.260 and 0.349 for A. hilliana and A. spondylophylla, respectively) genetic structure in both species. This indicates limited genetic connectivity via seed and pollen dispersal associated with Acacia species of small stature compared to taller tree and shrub acacias across the Pilbara bioregion. This effect of stature on genetic structure is superimposed on moderate levels of genetic diversity that were expected based on widespread ranges (haplotype diversity h = 25 and 12; nuclear diversity He = 0.60 and 0.47 for A. hilliana and A. spondylophylla, respectively). Contemporary genetic structure was congruent at the greater landscape scale, especially in terms of strong genetic differentiation among geographically disjunct populations in less elevated areas. Measures of diversity and connectivity were associated with traits of greater geographic population proximity, population density, population size, and greater individual longevity, and some evidence for range expansion in A. hilliana. Results illustrate that low stature is associated with limited dispersal and greater patterns of genetic differentiation for congenerics in a common landscape and highlight the complex influence of taxon-specific life history and ecological traits to seed and pollen dispersal.

2.
A A Pract ; 13(8): 292-294, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31265441

RESUMO

We present the case of a 51-year-old man with a history of recurrent lung cancer after left upper lobectomy who presented for an elective completion pneumonectomy via a bilateral anterior thoracotomy incision. At the completion of surgery, bilateral multilevel intercostal infiltration was performed with liposomal bupivacaine. Due to poorly controlled postoperative pain after extubation, a thoracic epidural was placed in the intensive care unit. An opioid-only infusion was started and transitioned to a local anesthetic-based infusion on postoperative day 2. This case report represents a novel stepwise approach of thoracic epidural management after surgical infiltration of liposomal bupivacaine.


Assuntos
Analgesia Epidural , Analgésicos Opioides/administração & dosagem , Anestésicos Locais/administração & dosagem , Bupivacaína/administração & dosagem , Dor Pós-Operatória/tratamento farmacológico , Analgesia Controlada pelo Paciente , Fentanila/administração & dosagem , Humanos , Hidromorfona/administração & dosagem , Masculino , Pessoa de Meia-Idade , Vértebras Torácicas
3.
Biol Rev Camb Philos Soc ; 94(3): 753-772, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30479069

RESUMO

The high species endemism characteristic of many of the world's terrestrial island systems provides a model for studying evolutionary patterns and processes, yet there has been no synthesis of studies to provide a systematic evaluation of terrestrial island systems in this context. The banded iron formations (BIFs) of south-western Australia are ancient terrestrial island formations occurring within a mosaic of alluvial clay soils, sandplains and occasional granite outcropping, across an old, gently undulating, highly weathered, plateau. Notably, these BIFs display exceptionally high beta plant diversity. Here, we address the determinants and consequences of genetic diversity for BIF-associated plant species through a comprehensive review of all studies on species distribution modelling, phylogenetics, phylogeography, population genetics, life-history traits and ecology. The taxa studied are predominantly narrowly endemic to individual or a few BIF ranges, but some have more regional distributions occurring both on and off BIFs. We compared genetic data for these BIF-endemic species to other localised species globally to assess whether the unique history and ancestry of BIF landscapes has driven distinct genetic responses in plants restricted to this habitat. We also assessed the influence of life-history parameters on patterns of genetic diversity. We found that BIF-endemic species display similar patterns of genetic diversity and structure to other species with localised distributions. Despite often highly restricted distributions, large effective population size or clonal reproduction appears to provide these BIF-endemic species with ecological and evolutionary resilience to environmental stochasticity. We conclude that persistence and stochasticity are key determinants of genetic diversity and its spatial structure within BIF-associated plant species, and that these are key evolutionary processes that should be considered in understanding the biogeography of inselbergs worldwide.


Assuntos
Ecossistema , Variação Genética , Plantas/genética , Austrália , Filogeografia , Processos Estocásticos
5.
Ann Bot ; 114(5): 961-71, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25100675

RESUMO

BACKGROUND AND AIMS: Understanding patterns of pollen dispersal and variation in mating systems provides insights into the evolutionary potential of plant species and how historically rare species with small disjunct populations persist over long time frames. This study aims to quantify the role of pollen dispersal and the mating system in maintaining contemporary levels of connectivity and facilitating persistence of small populations of the historically rare Acacia woodmaniorum. METHODS: Progeny arrays of A. woodmaniorum were genotyped with nine polymorphic microsatellite markers. A low number of fathers contributed to seed within single pods; therefore, sampling to remove bias of correlated paternity was implemented for further analysis. Pollen immigration and mating system parameters were then assessed in eight populations of varying size and degree of isolation. KEY RESULTS: Pollen immigration into small disjunct populations was extensive (mean minimum estimate 40 % and mean maximum estimate 57 % of progeny) and dispersal occurred over large distances (≤1870m). Pollen immigration resulted in large effective population sizes and was sufficient to ensure adaptive and inbreeding connectivity in small disjunct populations. High outcrossing (mean tm = 0·975) and a lack of apparent inbreeding suggested that a self-incompatibility mechanism is operating. Population parameters, including size and degree of geographic disjunction, were not useful predictors of pollen dispersal or components of the mating system. CONCLUSIONS: Extensive long-distance pollen dispersal and a highly outcrossed mating system are likely to play a key role in maintaining genetic diversity and limiting negative genetic effects of inbreeding and drift in small disjunct populations of A. woodmaniorum. It is proposed that maintenance of genetic connectivity through habitat and pollinator conservation will be a key factor in the persistence of this and other historically rare species with similar extensive long-distance pollen dispersal and highly outcrossed mating systems.


Assuntos
Acacia/fisiologia , Dispersão Vegetal/fisiologia , Pólen/fisiologia , Acacia/genética , Variação Genética , Genética Populacional , Genótipo , Geografia , Repetições de Microssatélites/genética , Pólen/genética , Polinização , Reprodução , Sementes/genética , Sementes/fisiologia
6.
J Endourol ; 27(5): 528-34, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23157176

RESUMO

PURPOSE: To provide a summary of the relevant literature regarding the impact of surgical cyst decortication on hypertension, renal function, and pain management in patients with autosomal dominant polycystic kidney disease (ADPKD). METHODS: Data collection was conducted via a Medline search using the subject headings autosomal dominant polycystic kidney disease, surgery, decortication, and marsupialization. Additional reports were derived from references included within these articles. RESULTS: Despite a trend for improved blood pressure control after cyst decortication in some studies, this cumulative review of the literature did not provide consistent evidence supporting the role of this procedure in blood pressure management in patients with ADPKD. Surgical cyst decortication was associated with renal deterioration in a subset of patients with compromised baseline renal function but did not otherwise appear to have a significant impact on renal function in the majority of studies reviewed. Improvement in chronic pain after this procedure was ubiquitously reported across all studies examined. CONCLUSIONS: Despite a potential role in blood pressure management in the setting of ADPKD, surgical cyst decortication has not been definitively shown to alleviate hypertension in this clinical setting. Renal function does not appear to improve following this surgery. Patients with compromised baseline renal function appear to be at increased risk for further deterioration in renal function after cyst decortication, although the role of this procedure in altering the natural trajectory of renal failure in this patient subset needs further investigation. Cyst decortication is highly effective in the management of disease-related chronic pain for the majority of patients with ADPKD, providing durable pain relief in this patient population.


Assuntos
Rim Policístico Autossômico Dominante/cirurgia , Hepatectomia/métodos , Humanos , Hipertensão/etiologia , Hipertensão/cirurgia , Dor/etiologia , Dor/cirurgia , Manejo da Dor , Rim Policístico Autossômico Dominante/complicações
7.
J Urol ; 188(4): 1239-44, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22902029

RESUMO

PURPOSE: Cyst proliferation in patients with autosomal dominant polycystic kidney disease is associated with renal failure, hypertension and pain. We examined the long-term impact of laparoscopic cyst decortication on renal function, hypertension and pain control in patients with adult dominant polycystic kidney disease presenting with refractory pain. MATERIALS AND METHODS: Between 1994 and 2003, 37 patients with adult dominant polycystic kidney disease underwent laparoscopic cyst decortication at Barnes-Jewish Hospital. A total of 19 patients (4 male, 15 female) with at least 3-year followup were included in the study. Renal function was evaluated using the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) estimated glomerular filtration rate formula. End stage renal disease was defined as progression to transplant, dialysis or stage 5 chronic kidney disease. Hypertension was evaluated using the antihypertensive therapeutic index. Pain assessment was based primarily on a telephone questionnaire. RESULTS: At a mean followup of 10.9 years (range 6.4 to 16.9), 67% of evaluable patients reported more than 50% improvement in pain. Ten patients had progression to end stage renal disease--3 dialysis, 6 transplant, and 1 chronic kidney disease stage 5. Two patients had stage 5 chronic kidney disease at initial presentation. A comparison of preoperative estimated glomerular filtration rate between patients with and those without end stage renal disease revealed a lower preoperative estimated glomerular filtration rate in the former group (43.4 vs 75.4 ml/minute/1.73 m(2), p = 0.01). Of the patients 53% had an improved or stable antihypertensive therapeutic index at last followup, although no improvement in mean overall antihypertensive therapeutic index was noted (4.7 pre-laparoscopic cyst decortications vs 7.0 post-laparoscopic cyst decortications, p = 0.28). CONCLUSIONS: Durable pain relief but not hypertension control was seen at 10-year followup. Preoperative estimated glomerular filtration rate is a strong predictor of post-laparoscopic cyst decortication progression to end stage renal disease. A cautious approach with laparoscopic cyst decortication should be taken in patients with poor preoperative renal function.


Assuntos
Laparoscopia , Nefrectomia/métodos , Rim Policístico Autossômico Dominante/fisiopatologia , Rim Policístico Autossômico Dominante/cirurgia , Adulto , Idoso , Feminino , Humanos , Hipertensão/etiologia , Hipertensão/terapia , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Manejo da Dor , Rim Policístico Autossômico Dominante/complicações , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
8.
Mol Ecol ; 21(13): 3187-99, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22582829

RESUMO

Acacia saligna is a species complex that has become invasive in a number of countries worldwide where it has caused substantial environmental and economic impacts. Understanding genetic and other factors contributing to its success may allow managers to limit future invasions of closely related species. We used three molecular markers to compare the introduced range (South Africa) to the native range (Western Australia). Nuclear markers showed that invasive populations are divergent from native populations and most closely related to a cultivated population in Western Australia. We also found incongruence between nuclear and chloroplast data that, together with the long history of cultivation of the species, suggest that introgressive hybridization (coupled with chloroplast capture) may have occurred within A. saligna. While we could not definitively prove introgression, the genetic distance between cultivated and native A. saligna populations was comparable to known interspecific divergences among other Acacia species. Therefore, cultivation, multiple large-scale introductions and possibly introgressive hybridization have rapidly given rise to the divergent genetic entity present in South Africa. This may explain the known global variation in invasiveness and inaccuracy of native bioclimatic models in predicting potential distributions.


Assuntos
Acacia/genética , Variação Genética , Genética Populacional , Espécies Introduzidas , Núcleo Celular/genética , DNA de Cloroplastos/genética , DNA de Plantas/genética , Marcadores Genéticos , Técnicas de Genotipagem , Repetições de Microssatélites , Dados de Sequência Molecular , Filogeografia , Análise de Sequência de DNA , África do Sul , Austrália Ocidental
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