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1.
PLoS Biol ; 19(10): e3001225, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34644303

RESUMEN

Plasmids play an important role in bacterial genome evolution by transferring genes between lineages. Fitness costs associated with plasmid carriage are expected to be a barrier to gene exchange, but the causes of plasmid fitness costs are poorly understood. Single compensatory mutations are often sufficient to completely ameliorate plasmid fitness costs, suggesting that such costs are caused by specific genetic conflicts rather than generic properties of plasmids, such as their size, metabolic burden, or gene expression level. By combining the results of experimental evolution with genetics and transcriptomics, we show here that fitness costs of 2 divergent large plasmids in Pseudomonas fluorescens are caused by inducing maladaptive expression of a chromosomal tailocin toxin operon. Mutations in single genes unrelated to the toxin operon, and located on either the chromosome or the plasmid, ameliorated the disruption associated with plasmid carriage. We identify one of these compensatory loci, the chromosomal gene PFLU4242, as the key mediator of the fitness costs of both plasmids, with the other compensatory loci either reducing expression of this gene or mitigating its deleterious effects by up-regulating a putative plasmid-borne ParAB operon. The chromosomal mobile genetic element Tn6291, which uses plasmids for transmission, remained up-regulated even in compensated strains, suggesting that mobile genetic elements communicate through pathways independent of general physiological disruption. Plasmid fitness costs caused by specific genetic conflicts are unlikely to act as a long-term barrier to horizontal gene transfer (HGT) due to their propensity for amelioration by single compensatory mutations, helping to explain why plasmids are so common in bacterial genomes.


Asunto(s)
Aptitud Genética , Mutación/genética , Plásmidos/genética , Cromosomas Bacterianos/genética , Conjugación Genética , Evolución Molecular , Regulación Bacteriana de la Expresión Génica , Modelos Biológicos , Pseudomonas fluorescens/genética , Transcripción Genética , Regulación hacia Arriba/genética
2.
BMC Pregnancy Childbirth ; 24(1): 65, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38225564

RESUMEN

BACKGROUND: Observational studies and randomized controlled trials have found evidence that higher maternal circulating cortisol levels in pregnancy are associated with lower offspring birth weight. However, it is possible that the observational associations are due to residual confounding. METHODS: We performed two-sample Mendelian Randomisation (MR) using a single genetic variant (rs9989237) associated with morning plasma cortisol (GWAS; sample 1; N = 25,314). The association between this maternal genetic variant and offspring birth weight, adjusted for fetal genotype, was obtained from the published EGG Consortium and UK Biobank meta-analysis (GWAS; sample 2; N = up to 406,063) and a Wald ratio was used to estimate the causal effect. We also performed an alternative analysis using all GWAS reported cortisol variants that takes account of linkage disequilibrium. We also tested the genetic variant's effect on pregnancy cortisol and performed PheWas to search for potential pleiotropic effects. RESULTS: The estimated effect of maternal circulating cortisol on birth weight was a 50 gram (95% CI, -109 to 10) lower birth weight per 1 SD higher log-transformed maternal circulating cortisol levels, using a single variant. The alternative analysis gave similar results (-33 grams (95% CI, -77 to 11)). The effect of the cortisol variant on pregnancy cortisol was 2-fold weaker than in the original GWAS, and evidence was found of pleiotropy. CONCLUSIONS: Our findings provide some evidence that higher maternal morning plasma cortisol causes lower birth weight. Identification of more independent genetic instruments for morning plasma cortisol are necessary to explore the potential bias identified.


Asunto(s)
Hidrocortisona , Análisis de la Aleatorización Mendeliana , Femenino , Humanos , Embarazo , Peso al Nacer/genética , Causalidad , Estudio de Asociación del Genoma Completo , Genotipo , Análisis de la Aleatorización Mendeliana/métodos , Polimorfismo de Nucleótido Simple , Recién Nacido
3.
Eur Child Adolesc Psychiatry ; 32(2): 317-330, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34417875

RESUMEN

The COVID-19 pandemic presents significant risks to population mental health. Despite evidence of detrimental effects for adults, there has been limited examination of the impact of COVID-19 on parents and children specifically. We aim to examine patterns of parent and child (0-18 years) mental health, parent substance use, couple conflict, parenting practices, and family functioning during COVID-19, compared to pre-pandemic data, and to identify families most at risk of poor outcomes according to pre-existing demographic and individual factors, and COVID-19 stressors. Participants were Australian mothers (81%) and fathers aged 18 years and over who were parents of a child 0-18 years (N = 2365). Parents completed an online self-report survey during 'stage three' COVID-19 restrictions in April 2020. Data were compared to pre-pandemic data from four Australian population-based cohorts. Compared to pre-pandemic estimates, during the pandemic period parents reported higher rates of parent depression, anxiety, and stress (Cohen's d = 0.26-0.81, all p < 0.001), higher parenting irritability (d = 0.17-0.46, all p < 0.001), lower family positive expressiveness (d = - 0.18, p < 0.001), and higher alcohol consumption (22% vs 12% drinking four or more days per week, p < 0.001). In multivariable analyses, we consistently found that younger parent age, increased financial deprivation, pre-existing parent and child physical and mental health conditions, COVID-19 psychological and environmental stressors, and housing dissatisfaction were associated with worse parent and child functioning and more strained family relationships. Our data suggest wide-ranging, detrimental family impacts associated with the COVID-19 pandemic; and support policy actions to assist families with financial supports, leave entitlements, and social housing.


Asunto(s)
COVID-19 , Adulto , Femenino , Niño , Humanos , Adolescente , COVID-19/epidemiología , Pandemias , Salud Mental , Australia/epidemiología , Padres/psicología , Responsabilidad Parental/psicología
4.
J Neurophysiol ; 125(6): 2361-2374, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33978497

RESUMEN

Motor learning is a core aspect of human life and appears to be ubiquitous throughout the animal kingdom. Dopamine, a neuromodulator with a multifaceted role in synaptic plasticity, may be a key signaling molecule for motor skill learning. Though typically studied in the context of reward-based associative learning, dopamine appears to be necessary for some types of motor learning. Mesencephalic dopamine structures are highly conserved among vertebrates, as are some of their primary targets within the basal ganglia, a subcortical circuit important for motor learning and motor control. With a focus on the benefits of cross-species comparisons, this review examines how "model-free" and "model-based" computational frameworks for understanding dopamine's role in associative learning may be applied to motor learning. The hypotheses that dopamine could drive motor learning either by functioning as a reward prediction error, through passive facilitating of normal basal ganglia activity, or through other mechanisms are examined in light of new studies using humans, rodents, and songbirds. Additionally, new paradigms that could enhance our understanding of dopamine's role in motor learning by bridging the gap between the theoretical literature on motor learning in humans and other species are discussed.


Asunto(s)
Encéfalo/fisiología , Dopamina/fisiología , Aprendizaje/fisiología , Modelos Biológicos , Destreza Motora/fisiología , Animales , Encéfalo/metabolismo , Dopamina/metabolismo , Humanos , Primates , Roedores , Pájaros Cantores
5.
Br Med Bull ; 139(1): 48-58, 2021 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-34227647

RESUMEN

INTRODUCTION: Open tibial fractures are the most common open long bone fracture, despite this, the management of these complex injuries still remains a topic of discussion amongst orthopaedic surgeons. SOURCES OF DATA: We searched the EMBASE, MEDLINE and Google Scholar and a systematic review of 7500 articles, leaving 23 after exclusion criteria were applied, in order to analyse the management of open tibial fractures. AREAS OF AGREEMENT AND CONTROVERSY: Infection was noted to be the most significant concern amongst authors, with definitive external fixation having a high rate of superficial pin-site infection and internal fixation having a high deep infection rate. GROWING POINTS: It is essential to have a combined ortho-plastic approach to the management of these fractures as muscle flaps were the most common form of soft tissue coverage. AREAS TIMELY FOR DEVELOPING RESEARCH: A national pragmatic trial into the management of open tibial fractures is required looking at fixation methods and soft tissue coverage, with at least a 2-year follow-up in order to ascertain the most appropriate management of these fractures and patient-related outcomes.


Asunto(s)
Fracturas Abiertas , Fracturas de la Tibia , Adulto , Fijación Interna de Fracturas , Fracturas Abiertas/cirugía , Humanos , Estudios Retrospectivos , Infección de la Herida Quirúrgica/terapia , Fracturas de la Tibia/cirugía , Resultado del Tratamiento
6.
Pancreatology ; 21(1): 1-14, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33376062

RESUMEN

BACKGROUND: Altered intestinal microbiota has been reported in pancreatic disorders, however, it remains unclear whether these changes alter the course of disease in patients with acute (AP) and chronic pancreatitis (CP), or whether these disease states alter the environment to enable pathogenic microbial composition changes to occur. We undertook a systematic review to characterize the gut microbiome in pancreatitis patients. METHODS: MEDLINE and EMBASE were searched for studies on microbiota in pancreatitis published from January 1, 2000 to June 5, 2020. Animal studies, reviews, case reports, and non-English articles were excluded. A frequency analysis was performed for outcomes reported in ≥2 studies and studies were analyzed for risk of bias and quality of evidence. RESULTS: 22 papers met inclusion criteria; 15 included AP, 7 included CP. No studies were appropriately designed to assess whether alterations in the gut microbiome exacerbate pancreatitis or develop as a result of pancreatitis. We did identify several patterns of microbiome changes that are associated with pancreatitis. The gut microbiome demonstrated decreased alpha diversity in 3/3 A P studies and 3/3 C P studies. Beta diversity analysis revealed differences in bacterial community composition in the gut microbiome in 2/2 A P studies and 3/3 C P studies. Functionally, gut microbiome changes were associated with infectious pathways in AP and CP. Several studies suffered from high risk of bias and inadequate quality. CONCLUSIONS: Detecting differences in microbial composition associated with AP and CP may represent a diagnostic tool. Appropriately controlled longitudinal studies are needed to determine whether microbiome changes are causative or reactive in pancreatitis.


Asunto(s)
Microbioma Gastrointestinal/fisiología , Pancreatitis/microbiología , Humanos , Pancreatitis/metabolismo , Pancreatitis Crónica/metabolismo , Pancreatitis Crónica/microbiología
7.
BMC Health Serv Res ; 21(1): 1240, 2021 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-34789234

RESUMEN

BACKGROUND: The COVID-19 pandemic and the associated economic recession has increased parental psychosocial stress and mental health challenges. This has adversely impacted child development and wellbeing, particularly for children from priority populations (culturally and linguistically diverse (CALD) and rural/regional communities) who are at an already increased risk of health inequality. The increased mental health and psychosocial needs were compounded by the closure of in-person preventive and health promotion programs resulting in health organisations embracing technology and online services. Watch Me Grow- Electronic (WMG-E) - developmental surveillance platform- exemplifies one such service. WMG-E was developed to monitor child development and guide parents towards more detailed assessments when risk is identified. This Randomised Controlled Trial (RCT) aims to expand WMG-E as a digital navigation tool by also incorporating parents' mental health and psychosocial needs. Children and families needing additional assessments and supports will be electronically directed to relevant resources in the 'care-as-usual' group. In contrast, the intervention group will receive continuity of care, with additional in-person assessment and 'warm hand over' by a 'service navigator' to ensure their needs are met. METHODS: Using an RCT we will determine: (1) parental engagement with developmental surveillance; (2) access to services for those with mental health and social care needs; and (3) uptake of service recommendations. Three hundred parents/carers of children aged 6 months to 3 years (recruited from a culturally diverse, or rural/regional site) will be randomly allocated to the 'care-as-usual' or 'intervention' group. A mixed methods implementation evaluation will be completed, with semi-structured interviews to ascertain the acceptability, feasibility and impact of the WMG-E platform and service navigator. CONCLUSIONS: Using WMG-E is expected to: normalise and de-stigmatise mental health and psychosocial screening; increase parental engagement and service use; and result in the early identification and management of child developmental needs, parental mental health, and family psychosocial needs. If effective, digital solutions such as WMG-E to engage and empower parents alongside a service navigator for vulnerable families needing additional support, will have significant practice and policy implications in the pandemic/post pandemic period. TRIAL REGISTRATION: The trial (Protocol No. 1.0, Version 3.1) was registered with ANZCTR (registration number: ACTRN12621000766819 ) on July 21st, 2021 and reporting of the trial results will be according to recommendations in the CONSORT Statement.


Asunto(s)
COVID-19 , Desarrollo Infantil , Niño , Electrónica , Humanos , Salud Mental , Padres , Ensayos Clínicos Controlados Aleatorios como Asunto , SARS-CoV-2
8.
Pediatr Cardiol ; 42(2): 389-396, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33179179

RESUMEN

Mastering pediatric echocardiography (PE) requires a substantial knowledge base of echo theory and congenital heart disease (CHD), along with technical proficiency. Online self-directed learning has become increasingly utilized among medical trainees to promote competency within medical subspecialties. We sought to evaluate the impact of online learning combined with lecture-based and hands-on teaching on the acquisition of PE knowledge and confidence in pediatric cardiology and pediatric critical care fellows. We prospectively enrolled 124 learners from 2016 to 2019. These included 40 incoming cardiology and critical care fellows at Texas Children's Hospital (TCH) as well as 84 national and international participants recruited from our online echo education website. All participants completed online learning modules through our website ( www.pedecho.org ), which covers pediatric echo physics, Doppler, technique, normal anatomy, atrial septal defects, and ventricular septal defects. TCH cardiology and critical care fellows subsequently participated in an Echo Boot Camp (BC), a 3-day training program with hands-on workshops and didactic lectures. Knowledge was assessed using an 80-question pre and post-test multiple choice exams. The online learning group demonstrated improvement in exam scores following online learning (PRE 49.1 ± 15.3 vs. POST 67.8 ± 17%; p ≤ 0.01). Echo Boot Camp fellows were noted to have further incremental improvement in test scores following BC (PRE 48% ± 13% vs. POST MODULE 68.6% ± 15% vs. POST BC 75.7% ± 13%; p ≤ 0.01). Self-assessment regarding confidence in context areas showed a substantial gain in self perceived interpretive confidence across all groups as well as procedural confidence in BC participants. Online learning significantly promotes the acquisition of echocardiography knowledge. Additional lecture-based and hands-on teaching in the form of an Echo Boot Camp can further enhance knowledge and interpretative skills. Both of these learning platforms appear to work in concert as powerful and effective tools in fellow education.


Asunto(s)
Cardiología/educación , Competencia Clínica , Ecocardiografía , Educación a Distancia/organización & administración , Niño , Curriculum , Femenino , Cardiopatías Congénitas/diagnóstico por imagen , Humanos , Internado y Residencia , Estudios Prospectivos
9.
Phys Rev Lett ; 124(2): 020401, 2020 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-32004025

RESUMEN

The theory of angular momentum connects physical rotations and quantum spins together at a fundamental level. Physical rotation of a quantum system will therefore affect fundamental quantum operations, such as spin rotations in projective Hilbert space, but these effects are subtle and experimentally challenging to observe due to the fragility of quantum coherence. We report on a measurement of a single-electron-spin phase shift arising directly from physical rotation, without transduction through magnetic fields or ancillary spins. This phase shift is observed by measuring the phase difference between a microwave driving field and a rotating two-level electron spin system, and it can accumulate nonlinearly in time. We detect the nonlinear phase using spin-echo interferometry of a single nitrogen-vacancy qubit in a diamond rotating at 200 000 rpm. Our measurements demonstrate the fundamental connections between spin, physical rotation, and quantum phase, and they will be applicable in schemes where the rotational degree of freedom of a quantum system is not fixed, such as spin-based rotation sensors and trapped nanoparticles containing spins.

10.
Proc Natl Acad Sci U S A ; 114(2): 239-244, 2017 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-28069959

RESUMEN

Domoic acid is a potent neurotoxin produced by certain marine microalgae that can accumulate in the foodweb, posing a health threat to human seafood consumers and wildlife in coastal regions worldwide. Evidence of climatic regulation of domoic acid in shellfish over the past 20 y in the Northern California Current regime is shown. The timing of elevated domoic acid is strongly related to warm phases of the Pacific Decadal Oscillation and the Oceanic Niño Index, an indicator of El Niño events. Ocean conditions in the northeast Pacific that are associated with warm phases of these indices, including changes in prevailing currents and advection of anomalously warm water masses onto the continental shelf, are hypothesized to contribute to increases in this toxin. We present an applied domoic acid risk assessment model for the US West Coast based on combined climatic and local variables. Evidence of regional- to basin-scale controls on domoic acid has not previously been presented. Our findings have implications in coastal zones worldwide that are affected by this toxin and are particularly relevant given the increased frequency of anomalously warm ocean conditions.


Asunto(s)
Bivalvos , Clima , Ácido Kaínico/análogos & derivados , Toxinas Marinas/análisis , Neurotoxinas/análisis , Animales , California , Monitoreo del Ambiente , Ácido Kaínico/análisis , Oregon , Mariscos/análisis , Washingtón
11.
Environ Monit Assess ; 192(8): 514, 2020 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-32666298

RESUMEN

Public health monitoring of Community Water Fluoridation (CWF) schemes requires estimates of exposure to fluoride in public water supplies (PWS). We aimed to use routine data to estimate population exposure to PWS-fluoride in England and to determine whether PWS-fluoride exposure from 2005 to 2015 could be used as a proxy for exposure for 1995-2004, when fluoride concentration data that could be linked to population health data were unavailable. We calculated annual mean water supply zone PWS-fluoride concentrations from monitoring data for 1995-2015, stratified by fluoridation scheme-flagging. We allocated annual 2005-2015 mean PWS-fluoride concentrations to small area boundaries to describe population exposure within five concentration categories (< 0.1 to ≥ 0.7 mg/L). We compared zone-level 1995-2004 and 2005-2015 mean PWS-fluoride concentrations using Spearman correlation. Most (72%) of the population received PWS with < 0.2 mg/L fluoride and 10% with ≥ 0.7 mg/L. Fluoride concentrations in 1995-2004 and 2005-2015 were similar (median 0.11 mg/L (lower quartile-upper quartile (LQ-UQ) 0.06-0.17) and 0.11 mg/L (LQ-UQ 0.07-0.17), respectively) and highly correlated (coefficient 0.93) if un-fluoridated but differed (1995-2004 median 0.78 mg/L (LQ-UQ 0.59-0.92); 2005-2015 0.84 mg/L (LQ-UQ 0.72-0.95)) and correlated weakly (coefficient 0.31) if fluoridated. Fluoride concentrations in 2005-2015 approximate those in 1995-2004 but with a greater risk of misclassification in fluoridation schemes.


Asunto(s)
Monitoreo del Ambiente , Fluoruros/análisis , Inglaterra , Fluoruración , Abastecimiento de Agua
12.
Proc Biol Sci ; 286(1903): 20190448, 2019 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-31113322

RESUMEN

In the wild, prey species often live in the vicinity of predators, rendering the ability to assess risk on a moment-to-moment basis crucial to survival. Visual cues are important as they allow prey to assess predator species, size, proximity and behaviour. However, few studies have explicitly examined prey's ability to assess risk based on predator behaviour and orientation. Using mosquitofish, Gambusia holbrooki, and their predator, jade perch, Scortum barcoo, under controlled conditions, we provide some of the first fine-scale characterization of how prey adapt their behaviour according to their continuous assessment of risk based on both predator behaviour and angular distance to the predator's mouth. When these predators were inactive and posed less of an immediate threat, prey within the attack cone of the predator showed reductions in speed and acceleration characteristic of predator-inspection behaviour. However, when predators became active, prey swam faster with greater acceleration and were closer together within the attack cone of predators. Most importantly, this study provides evidence that prey do not adopt a uniform response to the presence of a predator. Instead, we demonstrate that prey are capable of rapidly and dynamically updating their assessment of risk and showing fine-scale adjustments to their behaviour.


Asunto(s)
Ciprinodontiformes/fisiología , Cadena Alimentaria , Movimiento , Perciformes/fisiología , Conducta Predatoria , Animales , Conducta Animal
13.
Br J Surg ; 106(2): e34-e43, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30620068

RESUMEN

BACKGROUND: Effective dissemination of technology in global surgery is vital to realize universal health coverage by 2030. Challenges include a lack of human resource, infrastructure and finance. Understanding these challenges, and exploring opportunities and solutions to overcome them, are essential to improve global surgical care. METHODS: This review focuses on technologies and medical devices aimed at improving surgical care and training in low- and middle-income countries. The key considerations in the development of new technologies are described, along with strategies for evaluation and wider dissemination. Notable examples of where the dissemination of a new surgical technology has achieved impact are included. RESULTS: Employing the principles of frugal and responsible innovation, and aligning evaluation and development to high scientific standards help overcome some of the challenges in disseminating technology in global surgery. Exemplars of effective dissemination include low-cost laparoscopes, gasless laparoscopic techniques and innovative training programmes for laparoscopic surgery; low-cost and versatile external fixation devices for fractures; the LifeBox pulse oximeter project; and the use of immersive technologies in simulation, training and surgical care delivery. CONCLUSION: Core strategies to facilitate technology dissemination in global surgery include leveraging international funding, interdisciplinary collaboration involving all key stakeholders, and frugal scientific design, development and evaluation.


Asunto(s)
Tecnología Biomédica/métodos , Atención a la Salud/métodos , Difusión de Innovaciones , Cirugía General/métodos , Atención a la Salud/normas , Países en Desarrollo , Salud Global , Humanos
14.
Stud Mycol ; 92: 47-133, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29997401

RESUMEN

This paper represents the second contribution in the Genera of Phytopathogenic Fungi (GOPHY) series. The series provides morphological descriptions and information regarding the pathology, distribution, hosts and disease symptoms for the treated genera. In addition, primary and secondary DNA barcodes for the currently accepted species are included. This second paper in the GOPHY series treats 20 genera of phytopathogenic fungi and their relatives including: Allantophomopsiella, Apoharknessia, Cylindrocladiella, Diaporthe, Dichotomophthora, Gaeumannomyces, Harknessia, Huntiella, Macgarvieomyces, Metulocladosporiella, Microdochium, Oculimacula, Paraphoma, Phaeoacremonium, Phyllosticta, Proxypiricularia, Pyricularia, Stenocarpella, Utrechtiana and Wojnowiciella. This study includes the new genus Pyriculariomyces, 20 new species, five new combinations, and six typifications for older names.

15.
Proc Natl Acad Sci U S A ; 113(29): 8260-5, 2016 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-27385827

RESUMEN

Horizontal gene transfer is a fundamental process in bacterial evolution that can accelerate adaptation via the sharing of genes between lineages. Conjugative plasmids are the principal genetic elements mediating the horizontal transfer of genes, both within and between bacterial species. In some species, plasmids are unstable and likely to be lost through purifying selection, but when alternative hosts are available, interspecific plasmid transfer could counteract this and maintain access to plasmid-borne genes. To investigate the evolutionary importance of alternative hosts to plasmid population dynamics in an ecologically relevant environment, we established simple soil microcosm communities comprising two species of common soil bacteria, Pseudomonas fluorescens and Pseudomonas putida, and a mercury resistance (Hg(R)) plasmid, pQBR57, both with and without positive selection [i.e., addition of Hg(II)]. In single-species populations, plasmid stability varied between species: although pQBR57 survived both with and without positive selection in P. fluorescens, it was lost or replaced by nontransferable Hg(R) captured to the chromosome in P. putida A simple mathematical model suggests these differences were likely due to pQBR57's lower intraspecific conjugation rate in P. putida By contrast, in two-species communities, both models and experiments show that interspecific conjugation from P. fluorescens allowed pQBR57 to persist in P. putida via source-sink transfer dynamics. Moreover, the replacement of pQBR57 by nontransferable chromosomal Hg(R) in P. putida was slowed in coculture. Interspecific transfer allows plasmid survival in host species unable to sustain the plasmid in monoculture, promoting community-wide access to the plasmid-borne accessory gene pool and thus potentiating future evolvability.


Asunto(s)
Plásmidos/genética , Pseudomonas fluorescens/genética , Pseudomonas putida/genética , Microbiología del Suelo , Antibacterianos/farmacología , Mercurio/farmacología , Pseudomonas fluorescens/efectos de los fármacos , Pseudomonas putida/efectos de los fármacos
16.
BMC Evol Biol ; 18(1): 108, 2018 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-29986646

RESUMEN

BACKGROUND: Symbiosis is a major source of evolutionary innovation and, by allowing species to exploit new ecological niches, underpins the functioning of ecosystems. The transition from free-living to obligate symbiosis requires the alignment of the partners' fitness interests and the evolution of mutual dependence. While symbiotic taxa are known to vary widely in the extent of host-symbiont dependence, rather less is known about variation within symbiotic associations. RESULTS: Using experiments with the microbial symbiosis between the protist Paramecium bursaria and the alga Chlorella, we show variation between pairings in host-symbiont dependence, encompassing facultative associations, mutual dependence and host dependence upon the symbiont. Facultative associations, that is where both the host and the symbiont were capable of free-living growth, displayed higher symbiotic growth rates and higher per host symbiont loads than those with greater degrees of dependence. CONCLUSIONS: These data show that the Paramecium-Chlorella interaction exists at the boundary between facultative and obligate symbiosis, and further suggest that the host is more likely to evolve dependence than the algal symbiont.


Asunto(s)
Chlorella/fisiología , Paramecium/microbiología , Simbiosis/fisiología , Animales , Clorofila/metabolismo , Fluorescencia , Paramecium/crecimiento & desarrollo
17.
J Anat ; 232(5): 721-728, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29430649

RESUMEN

The Anatomical Society has developed a series of learning outcomes in consultation with nursing educators delivering anatomical content to undergraduate (preregistration) nursing students. A Delphi panel methodology was adopted to select experts within the field that would recommend core anatomical content in undergraduate nursing programmes throughout the UK. Using the Anatomical Society's Core Gross Anatomy Syllabus for Medical Students as a foundation, a modified Delphi technique was used to develop discipline-specific outcomes to nursing graduates. The Delphi panel consisted of 48 individuals (n = 48) with a minimum of 3 years' experience teaching anatomy to nursing students, representing a broad spectrum of UK Higher Education Institutions. The output from this study was 64 nursing specific learning outcomes in anatomy that are applicable to all undergraduate (preregistration) programmes in the UK. The new core anatomy syllabus for Undergraduate Nursing offers a basic anatomical framework upon which nurse educators, clinical mentors and nursing students can underpin their clinical practice and knowledge. The learning outcomes presented may be used to develop anatomy teaching within an integrated nursing curriculum.


Asunto(s)
Anatomía/educación , Curriculum/normas , Educación en Enfermería/normas
18.
Acta Neurol Scand ; 138(4): 293-300, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29749062

RESUMEN

OBJECTIVES: Stroke-associated pneumonia (SAP) is common and associated with adverse outcomes. Data on its impact beyond 1 year are scarce. MATERIALS AND METHODS: This observational study was conducted in a cohort of stroke patients admitted consecutively to a tertiary referral center in the east of England, UK (January 2003-April 2015). Logistic regression models examined inpatient mortality and length of stay (LOS). Cox regression models examined longer-term mortality at predefined time periods (0-90 days, 90 days-1 year, 1-3 years, and 3-10 years) for SAP. Effect of SAP on functional outcome at discharge was assessed using logistic regression. RESULTS: A total of 9238 patients (mean age [±SD] 77.61 ± 11.88 years) were included. SAP was diagnosed in 1083 (11.7%) patients. The majority of these cases (n = 658; 60.8%) were aspiration pneumonia. After controlling for age, sex, stroke type, Oxfordshire Community Stroke Project (OCSP) classification, prestroke modified Rankin scale, comorbidities, and acute illness markers, mortality estimates remained significant at 3 time periods: inpatient (OR 5.87, 95%CI [4.97-6.93]), 0-90 days (2.17 [1.97-2.40]), and 91-365 days (HR 1.31 [1.03-1.67]). SAP was also associated with higher odds of long LOS (OR 1.93 [1.67-2.22]) and worse functional outcome (OR 7.17 [5.44-9.45]). In this cohort, SAP did not increase mortality risk beyond 1 year post-stroke, but it was associated with reduced mortality beyond 3 years. CONCLUSIONS: Stroke-associated pneumonia is not associated with increased long-term mortality, but it is linked with increased mortality up to 1 year, prolonged LOS, and poor functional outcome on discharge. Targeted intervention strategies are required to improve outcomes of SAP patients who survive to hospital discharge.


Asunto(s)
Tiempo de Internación/tendencias , Neumonía/diagnóstico , Neumonía/mortalidad , Recuperación de la Función , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/mortalidad , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Comorbilidad , Femenino , Estudios de Seguimiento , Hospitalización/tendencias , Humanos , Masculino , Persona de Mediana Edad , Alta del Paciente/tendencias , Neumonía/etiología , Pronóstico , Accidente Cerebrovascular/complicaciones , Resultado del Tratamiento
19.
Scand J Med Sci Sports ; 28(1): 329-339, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28581692

RESUMEN

Traditionally a psychotherapeutic intervention, rational emotive behavior therapy (REBT) is receiving increasing attention within the extant literature as an intervention to enhance the athletic performance and psychological well-being of competitive athletes. Whilst the benefits of REBT on psychological health are established, less is understood about the effects on athletic performance. This study aimed to examine the immediate and maintained effects of REBT on physiological, psychological, and performance outcomes with elite Paralympic athletes. Using a single-case research design, eight athletes recruited from the same Paralympic sport (M=40.12, SD=12.99) received five, one-to-one REBT sessions. Measures of irrational beliefs were collected weekly, whereas the remaining psychological and physiological measures were collected at a pre-, post-, and at a 9-month follow-up time point. Visual and statistical analyzes of the data indicates reductions in irrational beliefs were coupled with reductions in systolic blood pressure indicative of an adaptive physiological response, improved athletic performance during competition simulations, and reductions in avoidance goals. Furthermore, social validation data indicated greater self-awareness, emotional control, and enhanced focus during competition as a result of the REBT intervention. This study contributes to growing literature supporting the efficacy of REBT as an intervention that not only facilitates psychological health but also enhances athletic performance. Results are discussed with reference to theory, limitations, and future recommendations.


Asunto(s)
Atletas/psicología , Rendimiento Atlético/psicología , Personas con Discapacidad/psicología , Emociones , Psicoterapia Racional-Emotiva , Adulto , Femenino , Humanos , Masculino , Salud Mental , Persona de Mediana Edad , Adulto Joven
20.
Br Med Bull ; 122(1): 135-149, 2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-28444129

RESUMEN

Introduction: This review aims to provide information on return rates and times to sport following stress fractures of the great toe sesamoids (SFGTSs). Sources of data: A systematic search of CINAHAL, Cochrane, EMBASE, Google Scholar, Medline, PEDro, Scopus, SPORTDiscus and Web of Science was performed using the keywords 'stress', 'fractures', 'great', 'toe', 'sesamoid', 'athletes', 'sports', 'non-operative', 'conservative', 'operative' and 'return to sport'. Areas of agreement: Fourteen studies were included: three studies reported on the outcome of conservatively-managed SFGTSs; thirteen studies reported on the outcome of surgically-managed SFGTSs. The management principles were to attempt conservative management for 2-6 months using activity modification, analgesia, orthotics and physiotherapy; if symptoms persisted following this, surgical management was to be recommended, either with internal fixation or sesamoidectomy. Areas of controversy: The optimal treatment modalities for SFGTSs remain to be defined. Growing points: Internal fixation shows the best return to full-level sport rates with low rates of complications. Areas timely for developing research: Future prospective studies should aim to establish the optimal treatment modalities for SFGTSs.


Asunto(s)
Fracturas por Estrés/terapia , Hallux/lesiones , Volver al Deporte , Humanos , Estudios Prospectivos , Deportes
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