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1.
Cardiol Young ; 33(12): 2657-2660, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37706367

RESUMO

Association of Pulmonary Artery Aneurysm with Ischemic Heart Disease is uncommon, and its surgical management has been rarely described in the literature. Surgical intervention should be individualised according to the coexisting diseases and comorbidities to achieve optimal outcome. We report a case of a 76-year-old man with background history of coronary artery stenting due to ischaemic heart disease. The patient presented with features of coronary compression due to giant pulmonary artery aneurysm. He was operated with replacement of aneurysmal pulmonary trunk with 25 mm Hancock conduit.


Assuntos
Aneurisma Coronário , Doença da Artéria Coronariana , Isquemia Miocárdica , Malformações Vasculares , Masculino , Humanos , Idoso , Aneurisma Coronário/diagnóstico , Aneurisma Coronário/diagnóstico por imagem , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/cirurgia , Doença da Artéria Coronariana/complicações , Isquemia Miocárdica/complicações , Isquemia Miocárdica/cirurgia , Malformações Vasculares/complicações
2.
Int J Health Plann Manage ; 38(1): 105-128, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36052725

RESUMO

OBJECTIVE: The aim of this study is to conceptualise and develop the Health Care Values Inventory (HEVAIN). For this purpose, we first explore key organizational values at different levels of the organisation. Then, we propose and validate a measurement scale based on the Triaxial system of values, which is represented by three axes, including ethical-social values, practical values (economic-pragmatic) and poietic (emotional). METHODS: Exploratory and confirmatory factor analysis were performed to check the validity of the proposed measurement scale. RESULTS: Using a sample of 535 employees from a semipublic healthcare organisation, the results showed that the HEVAIN measurement scale loaded satisfactorily onto three factors, and overcame the psychometric properties of dimensionality, reliability and validity. CONCLUSION: This research offers a new measurement scale to capture organizational values in healthcare organisations. This new tool provides both scholars and healthcare managers with an instrument to diagnose and manage organizational values, which gives key information to develop sustained competitive advantages.


Assuntos
Atenção à Saúde , Cultura Organizacional , Humanos , Reprodutibilidade dos Testes , Instalações de Saúde , Psicometria/métodos , Inquéritos e Questionários
3.
Molecules ; 28(3)2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36770902

RESUMO

Hispano-Muslim culture flourished during the Middle Ages in the Iberian Peninsula and Balearic Islands. During the restoration of a Balearic nobiliary building (casal), several panels with polychrome decoration on the back side were found. They were part of an old Muslim wooden ceiling (alfarje). A multi-technique strategy including optical microscopy, infrared and µRaman spectroscopies, field emission scanning electron microscopy-X-ray microanalysis (FESEM-EDX), focused ion beam (FIB-FESEM-EDX), atomic force microscopy nanoindentation (AFM-NI), and gas chromatography-mass spectrometry (GC-MS) has been applied in the analysis of these panel paintings and has provided morphological and compositional data that have led to the identification of the materials and artistic technique as well as the alteration mechanisms due to the natural aging and the adverse conditions of conservation. As a novelty, this study has confirmed the use of indigo as a blue pigment, an unusual material in Hispano-Muslim panel painting. Apart from the notable change in the visual appearance observed in the paintings, the study has also confirmed a change in the mechanical resistance in the paint layers. These changes have been induced by the combination of the chemical and microbiological alteration mechanisms identified.

4.
Mol Biol Evol ; 38(7): 2946-2957, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-33769517

RESUMO

Dissecting the genetic mechanisms underlying dioecy (i.e., separate female and male individuals) is critical for understanding the evolution of this pervasive reproductive strategy. Nonetheless, the genetic basis of sex determination remains unclear in many cases, especially in systems where dioecy has arisen recently. Within the economically important plant genus Solanum (∼2,000 species), dioecy is thought to have evolved independently at least 4 times across roughly 20 species. Here, we generate the first genome sequence of a dioecious Solanum and use it to ascertain the genetic basis of sex determination in this species. We de novo assembled and annotated the genome of Solanum appendiculatum (assembly size: ∼750 Mb scaffold N50: 0.92 Mb; ∼35,000 genes), identified sex-specific sequences and their locations in the genome, and inferred that males in this species are the heterogametic sex. We also analyzed gene expression patterns in floral tissues of males and females, finding approximately 100 genes that are differentially expressed between the sexes. These analyses, together with observed patterns of gene-family evolution specific to S. appendiculatum, consistently implicate a suite of genes from the regulatory network controlling pectin degradation and modification in the expression of sex. Furthermore, the genome of a species with a relatively young sex-determination system provides the foundational resources for future studies on the independent evolution of dioecy in this clade.


Assuntos
Evolução Biológica , Genoma de Planta , Processos de Determinação Sexual/genética , Solanum/genética , Regulação da Expressão Gênica de Plantas , Família Multigênica , Pectinas/genética
5.
Cardiol Young ; 32(7): 1098-1103, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34521485

RESUMO

OBJECTIVES: There are several studies reporting the outcomes of hypoplastic aortic arch and aortic coarctation repair with combination of techniques. However, only few studies reported of aortic arch and coarctation repair using a homograft patch through sternotomy and circulatory arrest with retrograde cerebral perfusion. We report our experience and outcomes of this cohort of neonates and infants. METHODS: We performed retrospective data collection for all neonates and infants who underwent aortic arch reconstruction between 2015 and 2020 at our institute. Data are presented as median and inter-quartile range (IQR). RESULTS: The cohort included 76 patients: 49 were males (64.5%). Median age at operation was 16 days (IQR 9-43.25 days). Median weight was 3.5 kg (IQR 3.10-4 kg). There was no 30 days mortality. Three patients died in hospital after 30 days (3.95%), neurological adverse events occurred in only one patient (1.32%) and recurrent laryngeal nerve injury was noted in four patients (5.26%). Only three patients required the support of extracorporeal membrane oxygenation (ECMO) with a median ECMO run of 4 days. Median follow-up was 35 months (IQR 18.9-46.4 months); 5 years survival was 93.42% (n = 71). The rate of re-intervention on the aortic arch was 9.21% (n = 7). CONCLUSION: Our experience shows excellent outcomes in repairing aortic arch hypoplasia with homograft patch under moderate to deep hypothermia with low in-hospital and 5 years mortality rates.


Assuntos
Coartação Aórtica , Procedimentos Cirúrgicos Cardíacos , Aorta Torácica/anormalidades , Aorta Torácica/cirurgia , Coartação Aórtica/cirurgia , Procedimentos Cirúrgicos Cardíacos/métodos , Criança , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/métodos
6.
Bioinformatics ; 36(Suppl_1): i219-i226, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32657391

RESUMO

MOTIVATION: The computational prediction of gene function is a key step in making full use of newly sequenced genomes. Function is generally predicted by transferring annotations from homologous genes or proteins for which experimental evidence exists. The 'ortholog conjecture' proposes that orthologous genes should be preferred when making such predictions, as they evolve functions more slowly than paralogous genes. Previous research has provided little support for the ortholog conjecture, though the incomplete nature of the data cast doubt on the conclusions. RESULTS: We use experimental annotations from over 40 000 proteins, drawn from over 80 000 publications, to revisit the ortholog conjecture in two pairs of species: (i) Homo sapiens and Mus musculus and (ii) Saccharomyces cerevisiae and Schizosaccharomyces pombe. By making a distinction between questions about the evolution of function versus questions about the prediction of function, we find strong evidence against the ortholog conjecture in the context of function prediction, though questions about the evolution of function remain difficult to address. In both pairs of species, we quantify the amount of information that would be ignored if paralogs are discarded, as well as the resulting loss in prediction accuracy. Taken as a whole, our results support the view that the types of homologs used for function transfer are largely irrelevant to the task of function prediction. Maximizing the amount of data used for this task, regardless of whether it comes from orthologs or paralogs, is most likely to lead to higher prediction accuracy. AVAILABILITY AND IMPLEMENTATION: https://github.com/predragradivojac/oc. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Genoma , Proteínas , Animais , Sequência de Bases , Evolução Molecular , Humanos , Camundongos , Proteínas/genética
7.
Proc Natl Acad Sci U S A ; 115(50): 12787-12792, 2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30482861

RESUMO

Convergent evolution-the appearance of the same character state in apparently unrelated organisms-is often inferred when a trait is incongruent with the species tree. However, trait incongruence can also arise from changes that occur on discordant gene trees, a process referred to as hemiplasy. Hemiplasy is rarely taken into account in studies of convergent evolution, despite the fact that phylogenomic studies have revealed rampant discordance. Here, we study the relative probabilities of homoplasy (including convergence and reversal) and hemiplasy for an incongruent trait. We derive expressions for the probabilities of the two events, showing that they depend on many of the same parameters. We find that hemiplasy is as likely-or more likely-than homoplasy for a wide range of conditions, even when levels of discordance are low. We also present a method to calculate the ratio of these two probabilities (the "hemiplasy risk factor") along the branches of a phylogeny of arbitrary length. Such calculations can be applied to any tree to identify when and where incongruent traits may be due to hemiplasy.


Assuntos
Genoma/genética , Filogenia , Animais , Evolução Molecular , Modelos Genéticos , Primatas , Probabilidade , Fatores de Risco
8.
Cardiol Young ; 31(2): 233-240, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33172515

RESUMO

OBJECTIVE: We aimed to examine the literature to determine if both paediatric and adult patients diagnosed with congenital heart disease (CHD) are at a higher risk of poor outcomes if they have the coronavirus disease 2019 (COVID-19), compared to those without CHD. METHODS: A systematic review was executed using the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. To identify articles related to COVID-19 and CHD, an extensive literature search was performed on EMBASE, Medline, Scopus, and Global Health databases using keywords and MeSH terms. RESULTS: A total of 12 articles met the inclusion criteria and were included for analysis in this systematic review. Two themes were identified for data extraction: evidence supporting higher risks in CHD patients and evidence against higher risks in CHD patients. After combining the data, there were 99 patients with CHDs out of which 12 required admissions to ICU. CONCLUSION: This systematic review suggests that CHD may increase the risk of poor outcomes for those with COVID-19, but also highlights the necessity for more research with larger sample sizes in order to make a more justified conclusion, as the majority of papers that were analysed were case series and case reports. Future research should aim to quantify the risks if possible whilst accounting for various confounding factors such as age and treatment history.


Assuntos
COVID-19/complicações , COVID-19/fisiopatologia , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/fisiopatologia , Adulto , COVID-19/mortalidade , Criança , Cardiopatias Congênitas/mortalidade , Humanos
9.
PLoS Genet ; 13(6): e1006817, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28604770

RESUMO

Species barriers, expressed as hybrid inviability and sterility, are often due to epistatic interactions between divergent loci from two lineages. Theoretical models indicate that the strength, direction, and complexity of these genetic interactions can strongly affect the expression of interspecific reproductive isolation and the rates at which new species evolve. Nonetheless, empirical analyses have not quantified the frequency with which loci are involved in interactions affecting hybrid fitness, and whether these loci predominantly interact synergistically or antagonistically, or preferentially involve loci that have strong individual effects on hybrid fitness. We systematically examined the prevalence of interactions between pairs of short chromosomal regions from one species (Solanum habrochaites) co-introgressed into a heterospecific genetic background (Solanum lycopersicum), using lines containing pairwise combinations of 15 chromosomal segments from S. habrochaites in the background of S. lycopersicum (i.e., 95 double introgression lines). We compared the strength of hybrid incompatibility (either pollen sterility or seed sterility) expressed in each double introgression line to the expected additive effect of its two component single introgressions. We found that epistasis was common among co-introgressed regions. Interactions for hybrid dysfunction were substantially more prevalent in pollen fertility compared to seed fertility phenotypes, and were overwhelmingly antagonistic (i.e., double hybrids were less unfit than expected from additive single introgression effects). This pervasive antagonism is expected to attenuate the rate at which hybrid infertility accumulates among lineages over time (i.e., giving diminishing returns as more reproductive isolation loci accumulate), as well as decouple patterns of accumulation of sterility loci and hybrid incompatibility phenotypes. This decoupling effect might explain observed differences between pollen and seed fertility in their fit to theoretical predictions of the accumulation of isolation loci, including the 'snowball' effect.


Assuntos
Cromossomos de Plantas/genética , Epistasia Genética , Locos de Características Quantitativas/genética , Isolamento Reprodutivo , Solanum lycopersicum/genética , Mapeamento Cromossômico , Fertilidade/genética , Genótipo , Hibridização Genética , Solanum lycopersicum/crescimento & desenvolvimento , Modelos Genéticos , Fenótipo , Infertilidade das Plantas/genética , Pólen/genética , Sementes/genética , Especificidade da Espécie
10.
Hum Mutat ; 40(9): 1373-1391, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31322791

RESUMO

Whole-genome sequencing (WGS) holds great potential as a diagnostic test. However, the majority of patients currently undergoing WGS lack a molecular diagnosis, largely due to the vast number of undiscovered disease genes and our inability to assess the pathogenicity of most genomic variants. The CAGI SickKids challenges attempted to address this knowledge gap by assessing state-of-the-art methods for clinical phenotype prediction from genomes. CAGI4 and CAGI5 participants were provided with WGS data and clinical descriptions of 25 and 24 undiagnosed patients from the SickKids Genome Clinic Project, respectively. Predictors were asked to identify primary and secondary causal variants. In addition, for CAGI5, groups had to match each genome to one of three disorder categories (neurologic, ophthalmologic, and connective), and separately to each patient. The performance of matching genomes to categories was no better than random but two groups performed significantly better than chance in matching genomes to patients. Two of the ten variants proposed by two groups in CAGI4 were deemed to be diagnostic, and several proposed pathogenic variants in CAGI5 are good candidates for phenotype expansion. We discuss implications for improving in silico assessment of genomic variants and identifying new disease genes.


Assuntos
Biologia Computacional/métodos , Variação Genética , Doenças não Diagnosticadas/diagnóstico , Adolescente , Criança , Pré-Escolar , Simulação por Computador , Bases de Dados Genéticas , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Fenótipo , Doenças não Diagnosticadas/genética , Sequenciamento Completo do Genoma
11.
Cardiol Young ; 29(11): 1361-1367, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31514764

RESUMO

INTRODUCTION: The way risk is interpreted by parents of children undergoing congenital cardiac surgery is poorly documented. Literature suggests clinicians have concerns that parents may not understand the complexity of procedures. Conversely, some parents perceive an unnecessary over-emphasis of risks. AIM: To explore how risk is encountered by parents of children who are undergoing cardiac surgery, in order to deliver effective and compassionate care. METHODS: A qualitative approach was adopted. Interviews were undertaken with 18 parents (mothers n = 10; fathers n = 8). Recordings were transcribed verbatim and analysed using a constant comparative-based approach. FINDINGS: Three themes emerged from the data: the nature of risk, reflecting the complexity of parental perception of risk and the influence of the doctor-parent relationship; presenting risk, highlighting the way in which risk is presented to and interpreted by parents; and risk and responsibility, examining the way in which parents engaged with risk and the impact of this on their relationship. CONCLUSIONS: The way in which risk is perceived by parents is complex and multi-factorial. The doctor-parent relationship is key to parental engagement. However, parents manage risk and uncertainty through a number of mechanisms, including those perceived as being not rational. This can cause tension, particularly when required to engage in informed decision-making.


Assuntos
Procedimentos Cirúrgicos Cardíacos/psicologia , Cardiopatias Congênitas/cirurgia , Pais/psicologia , Percepção/fisiologia , Médicos/psicologia , Relações Profissional-Família/ética , Pesquisa Qualitativa , Tomada de Decisões , Cardiopatias Congênitas/psicologia , Humanos
13.
Mol Ecol ; 27(2): 419-431, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29218792

RESUMO

Adaptive variation in social behaviour depends upon standing genetic variation, but we know little about how evolutionary forces shape genetic diversity relevant to brain and behaviour. In prairie voles (Microtus ochrogaster), variants at the Avpr1a locus predict expression of the vasopressin 1a receptor in the retrosplenial cortex (RSC), a brain region that mediates spatial and contextual memory; cortical V1aR abundance in turn predicts diversity in space use and sexual fidelity in the field. To examine the potential contributions of adaptive and neutral forces to variation at the Avpr1a locus, we explore sequence diversity at the Avpr1a locus and throughout the genome in two populations of wild prairie voles. First, we refine results demonstrating balancing selection at the locus by comparing the frequency spectrum of variants at the locus to a random sample of the genome. Next, we find that the four single nucleotide polymorphisms that predict high V1aR expression in the RSC are in stronger linkage disequilibrium than expected by chance despite high recombination among intervening variants, suggesting that epistatic selection maintains their association. Analysis of population structure and a haplotype network for two populations revealed that this excessive LD was unlikely to be due to admixture alone. Furthermore, the two populations differed considerably in the region shown to be a regulator of V1aR expression despite the extremely low levels of genomewide genetic differentiation. Together, our data suggest that complex selection on Avpr1a locus favours specific combinations of regulatory polymorphisms, maintains the resulting alleles at population-specific frequencies, and may contribute to unique patterns of spatial cognition and sexual fidelity among populations.


Assuntos
Arvicolinae/genética , Cognição/fisiologia , Receptores de Vasopressinas/genética , Comportamento Sexual Animal/fisiologia , Alelos , Animais , Arvicolinae/fisiologia , Encéfalo/fisiologia , Variação Genética , Repetições de Microssatélites/genética , Comportamento Social
14.
J Pediatr Gastroenterol Nutr ; 66(6): 949-952, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29601435

RESUMO

This study aimed to develop a severity prediction system for pediatric patients with acute pancreatitis (AP) based on clinical and laboratory parameters recorded at disease onset. A retrospective cohort study including 130 patients with AP, aged 0 to 18 years, was conducted. Correlations between severe AP (SAP) and clinical and laboratory data were established. Parameters with a significant statistical correlation (P ≤ 0.05) were incorporated in logistic regression models, and receiver operating characteristic curves were generated. The best-performance cutoff points were calculated to propose a severity prediction score, for which sensitivity and specificity were determined. Thirty-eight cases (29.2%) were consistent with SAP. A value of ≥1 point yielded a sensitivity of 81.5% and specificity of 64.1% for SAP prediction, when using a score including blood urea nitrogen ≥12.5 mg/dL (1 point) or hemoglobin <13 mg/dL (1 point) as variables. The proposed severity score showed good performance in predicting SAP.


Assuntos
Técnicas de Apoio para a Decisão , Pancreatite/diagnóstico , Índice de Gravidade de Doença , Doença Aguda , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Análise Multivariada , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
15.
Artigo em Inglês | MEDLINE | ID: mdl-29770974

RESUMO

Despite literature identifies aspects that might promote innovation, the relationship between the leadership style and nurses' innovative behavior still remains unclear, and little research has provided evidence of this. To help advance in knowledge of effects of leadership on nurses' innovative behavior, we researched the effect of altruistic leadership on nurses' innovative behavior. In addition, the mediating role of affiliative humor in the relationship between altruistic leadership and nurses' innovative behavior was examined. Questionnaire survey method was followed with a sample of 324 nurses working in public hospitals in Spain. We used structural equation models, to check the research hypotheses. This research reveals that affiliative humor partially mediates the relationship between altruistic leadership and nurses' innovative behavior. Thus, unselfish leaders are crucial to promoting innovative behaviors among nurses, and affiliative humor plays a fundamental role to explain how altruistic leaders enhance nurses' innovative behavior.

16.
BMC Plant Biol ; 17(1): 81, 2017 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-28438120

RESUMO

BACKGROUND: Unilateral incompatibility (UI) is an asymmetric reproductive barrier that unidirectionally prevents gene flow between species and/or populations. UI is characterized by a compatible interaction between partners in one direction, but in the reciprocal cross fertilization fails, generally due to pollen tube rejection by the pistil. Although UI has long been observed in crosses between different species, the underlying molecular mechanisms are only beginning to be characterized. The wild tomato relative Solanum habrochaites provides a unique study system to investigate the molecular basis of this reproductive barrier, as populations within the species exhibit both interspecific and interpopulation UI. Here we utilized a transcriptomic approach to identify genes in both pollen and pistil tissues that may be key players in UI. RESULTS: We confirmed UI at the pollen-pistil level between a self-incompatible population and a self-compatible population of S. habrochaites. A comparison of gene expression between pollinated styles exhibiting the incompatibility response and unpollinated controls revealed only a small number of differentially expressed transcripts. Many more differences in transcript profiles were identified between UI-competent versus UI-compromised reproductive tissues. A number of intriguing candidate genes were highly differentially expressed, including a putative pollen arabinogalactan protein, a stylar Kunitz family protease inhibitor, and a stylar peptide hormone Rapid ALkalinization Factor. Our data also provide transcriptomic evidence that fundamental processes including reactive oxygen species (ROS) signaling are likely key in UI pollen-pistil interactions between both populations and species. CONCLUSIONS: Gene expression analysis of reproductive tissues allowed us to better understand the molecular basis of interpopulation incompatibility at the level of pollen-pistil interactions. Our transcriptomic analysis highlighted specific genes, including those in ROS signaling pathways that warrant further study in investigations of UI. To our knowledge, this is the first report to identify candidate genes involved in unilateral barriers between populations within a species.


Assuntos
Flores/genética , Genes de Plantas , Pólen/genética , Solanum/genética , Flores/fisiologia , Expressão Gênica , Perfilação da Expressão Gênica , Pólen/fisiologia , Solanum/fisiologia
17.
Proc Biol Sci ; 284(1856)2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28615505

RESUMO

Molecular interactions affect the evolution of complex traits. For instance, adaptation may be constrained by pleiotropic or epistatic effects, both of which can be reflected in the structure of molecular interaction networks. To date, empirical studies investigating the role of molecular interactions in phenotypic evolution have been idiosyncratic, offering no clear patterns. Here, we investigated the network topology of genes putatively involved in local adaptation to two abiotic stressors-drought and cold-in Arabidopsis thaliana Our findings suggest that the gene-interaction topologies for both cold and drought stress response are non-random, with genes that show genetic variation in drought expression response (eGxE) being significantly more peripheral and cold response genes being significantly more central than genes which do not show GxE. We suggest that the observed topologies reflect different constraints on the genetic pathways involved in environmental response. The approach presented here may inform predictive models linking genetic variation in molecular signalling networks with phenotypic variation, specifically traits involved in environmental response.


Assuntos
Adaptação Fisiológica/genética , Arabidopsis/genética , Temperatura Baixa , Secas , Redes Reguladoras de Genes , Arabidopsis/fisiologia , Regulação da Expressão Gênica de Plantas
18.
Mol Ecol ; 26(20): 5362-5368, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28792649

RESUMO

Because they are considered rare, balanced polymorphisms are often discounted as crucial constituents of genome-wide variation in sequence diversity. Despite its perceived rarity, however, long-term balancing selection can elevate genetic diversity and significantly affect observed divergence between species. Here, we discuss how ancestral balanced polymorphisms can be "sieved" by the speciation process, which sorts them unequally across descendant lineages. After speciation, ancestral balancing selection is revealed by genomic regions of high divergence between species. This signature, which resembles that of other evolutionary processes, can potentially confound genomic studies of population divergence and inferences of "islands of speciation."


Assuntos
Especiação Genética , Modelos Genéticos , Polimorfismo Genético , Alelos , Fluxo Gênico , Frequência do Gene , Genética Populacional , Genômica
19.
Pediatr Crit Care Med ; 18(7): 647-654, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28489637

RESUMO

OBJECTIVES: To determine the hemodynamic effect of tracheal suction method in the first 36 hours after high-risk infant heart surgery on the PICU and to compare open and closed suctioning techniques. DESIGN: Pilot randomized crossover study. SETTING: Single PICU in United Kingdom. PARTICIPANTS: Infants undergoing surgical palliation with Norwood Sano, modified Blalock-Taussig shunt, or pulmonary artery banding in the first 36 hours postoperatively. INTERVENTIONS: Infants were randomized to receive open or closed (in-line) tracheal suctioning either for their first or second study tracheal suction in the first 36 hours postoperatively. MEASUREMENTS AND MAIN RESULTS: Twenty-four infants were enrolled over 18 months, 11 after modified Blalock-Taussig shunt, seven after Norwood Sano, and six after pulmonary artery banding. Thirteen patients received the open suction method first followed by the closed suction method second, and 11 patients received the closed suction method first followed by the open suction method second in the first 36 hours after their surgery. There were statistically significant larger changes in heart rate (p = 0.002), systolic blood pressure (p = 0.022), diastolic blood pressure (p = 0.009), mean blood pressure (p = 0.007), and arterial saturation (p = 0.040) using the open suction method, compared with closed suctioning, although none were clinically significant (defined as requiring any intervention). CONCLUSIONS: There were no clinically significant differences between closed and open tracheal suction methods; however, there were statistically significant greater changes in some hemodynamic variables with open tracheal suctioning, suggesting that closed technique may be safer in children with more precarious physiology.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cuidados Críticos/métodos , Cardiopatias Congênitas/cirurgia , Intubação Intratraqueal , Cuidados Pós-Operatórios/métodos , Sucção/métodos , Estudos Cross-Over , Feminino , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva Pediátrica , Masculino , Projetos Piloto , Resultado do Tratamento
20.
Mol Ecol ; 25(11): 2592-608, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27136303

RESUMO

Little is known about the physiological responses and genetic mutations associated with reproductive isolation between species, especially for postmating prezygotic isolating barriers. Here, we examine changes in gene expression that accompany the expression of 'unilateral incompatibility' (UI)-a postmating prezygotic barrier in which fertilization is prevented by gamete rejection in the reproductive tract [in this case of pollen tubes (male gametophytes)] in one direction of a species cross, but is successful in the reciprocal crossing direction. We use whole-transcriptome sequencing of multiple developmental stages of male and female tissues in two Solanum species that exhibit UI to: (i) identify transcript differences between UI-competent and UI noncompetent tissues; (ii) characterize transcriptional changes specifically associated with the phenotypic expression of UI; and (iii) using these comparisons, evaluate the behaviour of a priori candidate loci for UI and identify new candidates for future manipulative work. In addition to describing transcriptome-wide changes in gene expression that accompany this isolating barrier, we identify at least five strong candidates for involvement in postmating prezygotic incompatibility between species. These include three novel candidates and two candidates that are strongly supported by prior developmental, functional, and quantitative trait locus mapping studies. These latter genes are known molecular players in the intraspecific expression of mate choice via genetic self-incompatibility, and our study supports prior evidence that these inter- and intraspecific postmating prezygotic reproductive behaviours share specific genetic and molecular mechanisms.


Assuntos
Perfilação da Expressão Gênica , Isolamento Reprodutivo , Solanum/genética , Transcriptoma , Mapeamento Cromossômico , Cruzamentos Genéticos , Genes de Plantas , Fenótipo , Pólen/genética , RNA de Plantas/genética , Reprodução/genética , Solanum/fisiologia
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