Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 97
Filtrar
1.
Mol Biol Evol ; 41(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38401262

RESUMEN

Hypolimnas misippus is a Batesian mimic of the toxic African Queen butterfly (Danaus chrysippus). Female H. misippus butterflies use two major wing patterning loci (M and A) to imitate three color morphs of D. chrysippus found in different regions of Africa. In this study, we examine the evolution of the M locus and identify it as an example of adaptive atavism. This phenomenon involves a morphological reversion to an ancestral character that results in an adaptive phenotype. We show that H. misippus has re-evolved an ancestral wing pattern present in other Hypolimnas species, repurposing it for Batesian mimicry of a D. chrysippus morph. Using haplotagging, a linked-read sequencing technology, and our new analytical tool, Wrath, we discover two large transposable element insertions located at the M locus and establish that these insertions are present in the dominant allele responsible for producing mimetic phenotype. By conducting a comparative analysis involving additional Hypolimnas species, we demonstrate that the dominant allele is derived. This suggests that, in the derived allele, the transposable elements disrupt a cis-regulatory element, leading to the reversion to an ancestral phenotype that is then utilized for Batesian mimicry of a distinct model, a different morph of D. chrysippus. Our findings present a compelling instance of convergent evolution and adaptive atavism, in which the same pattern element has independently evolved multiple times in Hypolimnas butterflies, repeatedly playing a role in Batesian mimicry of diverse model species.


Asunto(s)
Mimetismo Biológico , Mariposas Diurnas , Animales , Mariposas Diurnas/genética , Elementos Transponibles de ADN , Mimetismo Biológico/genética , Fenotipo , África , Alas de Animales/anatomía & histología
2.
Ecol Evol ; 14(2): e11024, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38414566

RESUMEN

Scoring the penetrance of heterozygotes in complex phenotypes, like colour pattern, is difficult and complicates the analysis of systems in which dominance is incomplete or evolving. The African Monarch (Danaus chrysippus) represents an example where colour pattern heterozygotes, formed in the contact zone between the different subspecies, show such intermediate dominance. Colour pattern in this aposematic butterfly is controlled by three loci A, B and C. The B and C loci are closely linked in a B/C supergene and significant interaction of B and C phenotypes is therefore expected via linkage alone. The A locus, however, is not linked to B/C and is found on a different chromosome. To study interactions between these loci we generated colour pattern heterozygotes by crossing males and females bearing different A and B/C genotypes, collected from different parts of Africa. We derived a novel scoring system for the expressivity of the heterozygotes and, as predicted, we found significant interactions between the genotypes of the closely linked B and C loci. Surprisingly, however, we also found highly significant interactions between C and the unlinked A locus, modifications that generally increased the resemblance of heterozygotes to homozygous ancestors. In contrast, we found no difference in the penetrance of any of the corresponding heterozygotes from crosses conducted either in allopatry or sympatry, in reciprocal crosses of males and females, or in the presence or absence of endosymbiont mediated male-killing or its associated neoW mediated sex-linkage of colour pattern. Together, this data supports the idea that the different colour morphs of the African Monarch meet transiently in the East African contact zone and that genetic modifiers act to mask inappropriate expression of colour patterns in the incorrect environments.

3.
PeerJ ; 11: e15853, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37601261

RESUMEN

Background: Sexual selection and conflicts within and between sexes promote morphological diversity of reproductive traits within species. Variation in the morphology of diagnostic reproductive characters within species offer an excellent opportunity to study these evolutionary processes as drivers of species diversification. The African monarch, Danaus chrysippus (Linnaeus, 1758), is widespread across Africa. The species is polytypic, with the respective geographical ranges of the four colour morphs only overlapping in East Africa. Furthermore, some of the populations host an endosymbiotic bacterium, Spiroplasma, which induces son-killing and distorts the local host population sex-ratio, creating sexual conflicts between the females seeking to optimize their fecundity and the limited mating capacity of the rare males. Methods: We dissected females from Kenya, Rwanda and South Africa, where Spiroplasma vary in presence and prevalence (high, variable and absent, respectively), and conducted microscopy imaging of their reproductive organs. We then characterized the effect of population, female body size, and female mating status, on the size and shape of different genitalia characters of the D. chrysippus female butterflies. Results: We showed that although the general morphology of the organs is conserved in D. chrysippus, female genitalia vary in size and shape between and within populations. The virgin females have smaller organs, while the same organs were expanded in mated females. Females from highly female-biased populations, where the male-killing Spiroplasma is prevalent, also have a larger area of their corpus bursae covered with signa structures. However, this pattern occurs because a larger proportion of the females remains virgin in the female-biased populations rather than because of male depletion due to the symbiont, as males from sex-ratio distorted populations did not produce significantly smaller nutritious spermatophores.


Asunto(s)
Mariposas Diurnas , Femenino , Masculino , Animales , Genitales , Reproducción , Fertilidad , Kenia
4.
Ecol Evol ; 13(4): e9956, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37021082

RESUMEN

In butterflies and moths, male-killing endosymbionts are transmitted from infected females via their eggs, and the male progeny then perish. This means that successful transmission of the parasite relies on the successful mating of the host. Paradoxically, at the population level, parasite transmission also reduces the number of adult males present in the final population for infected females to mate with. Here we investigate if successful female mating when males are rare is indeed a likely rate-limiting step in the transmission of male-killing Spiroplasma in the African Monarch, Danaus chrysippus. In Lepidoptera, successful pairings are hallmarked by the transfer of a sperm-containing spermatophore from the male to the female during copulation. Conveniently, this spermatophore remains detectable within the female upon dissection, and thus, spermatophore counts can be used to assess the frequency of successful mating in the field. We used such spermatophore counts to examine if altered sex ratios in the D. chrysippus do indeed affect female mating success. We examined two different field sites in East Africa where males were often rare. Surprisingly, mated females carried an average of 1.5 spermatophores each, regardless of male frequency, and importantly, only 10-20% remained unmated. This suggests that infected females will still be able to mate in the face of either Spiroplasma-mediated male killing and/or fluctuations in adult sex ratio over the wet-dry season cycle. These observations may begin to explain how the male-killing mollicute can still be successfully transmitted in a population where males are rare.

5.
Int Small Bus J ; 40(6): 684-709, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36147205

RESUMEN

Recent contributions to the literature on small firm growth have been marked by a growing sense of frustration with the state-of-the-art and what it implicates in both theory and policy. In short, while growth episodes appear relatively common, a tiny proportion of firms sustain growth and 'scale'. This calls into question the very basis upon which policies seeking to target high growth firms (HGFs) rest. In addition, it cautions against perspectives that view growth as the essence of entrepreneurship. In this paper, we argue that understanding the frequency of growth episodes and the rarity of sustained growth requires a better understanding of growth consequences. To this end, we describe case study evidence from ambitious entrepreneurs whose firms experienced an episode of high growth followed by longer periods of mixed performance. Our goal is to shed light on how the experience of growing affects further growth. Our data provide initial insights into the mechanisms linking past growth to growth motivations and into the ways in which past growth lays the foundations for future performance.

6.
Philos Trans R Soc Lond B Biol Sci ; 377(1856): 20210207, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35694743

RESUMEN

Supergenes maintain adaptive clusters of alleles in the face of genetic mixing. Although usually attributed to inversions, supergenes can be complex, and reconstructing the precise processes that led to recombination suppression and their timing is challenging. We investigated the origin of the BC supergene, which controls variation in warning coloration in the African monarch butterfly, Danaus chrysippus. By generating chromosome-scale assemblies for all three alleles, we identified multiple structural differences. Most strikingly, we find that a region of more than 1 million bp underwent several segmental duplications at least 7.5 Ma. The resulting duplicated fragments appear to have triggered four inversions in surrounding parts of the chromosome, resulting in stepwise growth of the region of suppressed recombination. Phylogenies for the inversions are incongruent with the species tree and suggest that structural polymorphisms have persisted for at least 4.1 Myr. In addition to the role of duplications in triggering inversions, our results suggest a previously undescribed mechanism of recombination suppression through independent losses of divergent duplicated tracts. Overall, our findings add support for a stepwise model of supergene evolution involving a variety of structural changes. This article is part of the theme issue 'Genomic architecture of supergenes: causes and evolutionary consequences'.


Asunto(s)
Mariposas Diurnas , Alelos , Animales , Mariposas Diurnas/genética , Inversión Cromosómica , Evolución Molecular , Filogenia , Polimorfismo Genético
7.
Biol Lett ; 18(6): 20210639, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35642381

RESUMEN

Warning coloration provides a textbook example of natural selection, but the frequent observation of polymorphism in aposematic species presents an evolutionary puzzle. We investigated biogeography and polymorphism of warning patterns in the widespread butterfly Danaus chrysippus using records from citizen science (n = 5467), museums (n = 8864) and fieldwork (n = 2586). We find that polymorphism in three traits controlled by known mendelian loci is extensive. Broad allele frequency clines, hundreds of kilometres wide, suggest a balance between long-range dispersal and predation of unfamiliar morphs. Mismatched clines for the white hindwing and forewing tip in East Africa are consistent with a previous finding that the black wingtip allele has spread recently in the region through hitchhiking with a heritable endosymbiont. Light/dark background coloration shows more extensive polymorphism. The darker genotype is more common in cooler regions, possibly reflecting a trade-off between thermoregulation and predator warning. Overall, our findings show how studying local adaptation at the global scale provides a more complete picture of the evolutionary forces involved.


Asunto(s)
Mariposas Diurnas , Pigmentación , Adaptación Biológica , Animales , Evolución Biológica , Mariposas Diurnas/genética , Ciencia Ciudadana , Frecuencia de los Genes , Fenotipo , Conducta Predatoria , Selección Genética
8.
Biol J Linn Soc Lond ; 133(3): 671-684, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34539176

RESUMEN

Heterosis, Haldane and Bateson-Dobzhansky-Muller effects have been widely documented amongst a range of plants and animals. However, typically these effects are shown by taking parents of known genotype into the laboratory and measuring components of the F1 progeny under laboratory conditions. This leaves in doubt the real significance of such effects in the field. Here we use the well-known colour pattern genotypes of the African monarch or queen (Danaus chrysippus), which also control wing length, to test these effects both in the laboratory and in a contact zone in the field. By measuring the wing lengths in animals of known colour pattern genotype we show clear evidence for all three hybrid effects at the A and BC colour patterning loci, and importantly, that these same effects persist in the same presumptive F1s when measured in hybrid populations in the field. This demonstrates the power of a system in which genotypes can be directly inferred in the field and highlights that all three hybrid effects can be seen in the East African contact zone of this fascinating butterfly.

9.
Thorax ; 76(7): 656-663, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33323480

RESUMEN

PURPOSE: To investigate the effect of functional electrical stimulation-assisted cycle ergometry (FES-cycling) on muscle strength, cognitive impairment and related outcomes. METHODS: Mechanically ventilated patients aged ≥18 years with sepsis or systemic inflammatory response syndrome were randomised to either 60 min of FES-cycling >5 days/week while in the intensive care unit (ICU) plus usual care rehabilitation versus usual care rehabilitation alone, with evaluation of two primary outcomes: (1) muscle strength at hospital discharge and (2) cognitive impairment at 6-month follow-up. RESULTS: We enrolled 162 participants, across four study sites experienced in ICU rehabilitation in Australia and the USA, to FES-cycling (n=80; mean age±SD 59±15) versus control (n=82; 56±14). Intervention participants received a median (IQR) of 5 (3-9) FES-cycling sessions with duration of 56 (34-63) min/day plus 15 (10-23) min/day of usual care rehabilitation. The control group received 15 (8-15) min/day of usual care rehabilitation. In the intervention versus control group, there was no significant differences for muscle strength at hospital discharge (mean difference (95% CI) 3.3 (-5.0 to 12.1) Nm), prevalence of cognitive impairment at 6 months (OR 1.1 (95% CI 0.30 to 3.8)) or secondary outcomes measured in-hospital and at 6 and 12 months follow-up. CONCLUSION: In this randomised controlled trial, undertaken at four centres with established rehabilitation programmes, the addition of FES-cycling to usual care rehabilitation did not substantially increase muscle strength at hospital discharge. At 6 months, the incidence of cognitive impairment was almost identical between groups, but potential benefit or harm of the intervention on cognition cannot be excluded due to imprecision of the estimated effect. TRIAL REGISTRATION NUMBER: ACTRN 12612000528853, NCT02214823.


Asunto(s)
Enfermedad Crítica/rehabilitación , Estimulación Eléctrica/métodos , Terapia por Ejercicio/métodos , Unidades de Cuidados Intensivos , Fuerza Muscular/fisiología , Calidad de Vida , Respiración Artificial/métodos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Método Simple Ciego
10.
Circulation ; 142(14): 1330-1338, 2020 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-33017209

RESUMEN

BACKGROUND: An internal thoracic artery graft to the left anterior descending artery is standard in coronary bypass surgery, but controversy exists on the best second conduit. The RAPCO trials (Radial Artery Patency and Clinical Outcomes) were designed to compare the long-term patency of the radial artery (RA) with that of the right internal thoracic artery (RITA) and the saphenous vein (SV). METHODS: In RAPCO-RITA (the RITA versus RA arm of the RAPCO trial), 394 patients <70 years of age (or <60 years of age if they had diabetes mellitus) were randomized to receive RA or free RITA graft on the second most important coronary target. In RAPCO-SV (the SV versus RA arm of the RAPCO trial), 225 patients ≥70 years of age (or ≥60 years of age if they had diabetes mellitus) were randomized to receive RA or SV graft. The primary outcome was 10-year graft failure. Long-term mortality was a nonpowered coprimary end point. The main analysis was by intention to treat. RESULTS: In the RA versus RITA comparison, the estimated 10-year patency was 89% for RA versus 80% for free RITA (hazard ratio for graft failure, 0.45 [95% CI, 0.23-0.88]). Ten-year patient survival estimate was 90.9% in the RA arm versus 83.7% in the RITA arm (hazard ratio for mortality, 0.53 [95% CI, 0.30-0.95]). In the RA versus SV comparison, the estimated 10-year patency was 85% for the RA versus 71% for the SV (hazard ratio for graft failure, 0.40 [95% CI, 0.15-1.00]), and 10-year patient survival estimate was 72.6% for the RA group versus 65.2% for the SV group (hazard ratio for mortality, 0.76 [95% CI, 0.47-1.22]). CONCLUSIONS: The 10-year patency rate of the RA is significantly higher than that of the free RITA and better than that of the SV. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00475488.


Asunto(s)
Puente de Arteria Coronaria , Arterias Mamarias , Mortalidad , Arteria Radial , Grado de Desobstrucción Vascular , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tasa de Supervivencia
11.
Chem Senses ; 45(8): 635-644, 2020 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-32866968

RESUMEN

Visual and olfactory communications are vital for coordinated group hunting in most animals. To hunt for prey, the group-raiding termite specialist ant Megaponera analis, which lacks good vision, must first confirm the presence or absence of conspecific raiders. Here, we show that M. analis uses olfactory cues for intraspecific communication and showed greater preference for conspecific odors over clean air (blank) or odors from its termite prey. Chemical analysis of ant volatiles identified predominantly short-chained hydrocarbons. Electrophysiological analysis revealed differential sensory detection of the odor compounds, which were confirmed in behavioral olfactometric choice assays with odor bouquets collected from major and minor castes and the 2 most dominant volatiles and n-undecane n-tridecane. A comparative analysis of the cuticular hydrocarbon profile with those of the short-chained odor bouquet of different populations shows a high divergence in the long-chained profile and a much-conserved short-chained odor bouquet. This suggests that there is less selection pressure for divergence and individual recognition in the short- than the long-chained odor profiles. We conclude that olfactory communication serves as an alternative to visual or sound communication, especially during group raids in M. analis when ants are not in direct contact with one another.


Asunto(s)
Hidrocarburos/análisis , Odorantes/análisis , Animales , Hormigas , Volatilización
12.
Clin Transl Immunology ; 9(5): e1127, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32377339

RESUMEN

OBJECTIVES: To facilitate disease prognosis and improve precise immunotherapy of gastric cancer (GC) patients, a comprehensive study integrating immune cellular and molecular analyses on tumor tissues and peripheral blood was performed. METHODS: The association of GC patients' outcomes and the immune context of their tumors was explored using multiplex immunohistochemistry (mIHC) and transcriptome profiling. Potential immune dysfunction mechanism/s in the tumors on the systemic level was further examined using mass cytometry (CyTOF) in complementary peripheral blood from selected patients. GC cohorts with mIHC and gene expression profiling data were also used as validation cohorts. RESULTS: Increased CD4+FOXP3+ T-cell density in the GC tumor correlated with prolonged survival. Interestingly, CD4+FOXP3+ T cells had a close interaction with CD8+ T cells rather than tumor cells. High densities of CD4+FOXP3+ T cells and CD8+ T cells (High-High) independently predicted prolonged patient survival. Furthermore, the interferon-gamma (IFN-γ) gene signature and PDL1 expression were up-regulated in this group. Importantly, a subgroup of genomically stable (GS) tumors and tumors with chromosomal instability (CIN) within this High-High group also had excellent survival. The High-High GS/CIN tumors were coupled with increased frequencies of Tbet+CD4+ T cells and central memory CD4+ T cells in the peripheral blood. CONCLUSION: These novel findings identify the combination of CD8+ T cells and FOXP3+CD4+ T cells as a significant prognostic marker for GC patients, which also could potentially be targeted and applied in the combination therapy with immune checkpoint blockades in precision medicine.

13.
BMJ Open ; 10(5): e035613, 2020 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-32371516

RESUMEN

INTRODUCTION: The number of inconclusive physical rehabilitation randomised controlled trials for patients with critical illness is increasing. Evidence suggests critical illness patient subgroups may exist that benefit from targeted physical rehabilitation interventions that could improve their recovery trajectory. We aim to identify critical illness patient subgroups that respond to physical rehabilitation and map recovery trajectories according to physical function and quality of life outcomes. Additionally, the utilisation of healthcare resources will be examined for subgroups identified. METHODS AND ANALYSIS: This is an individual participant data meta-analysis protocol. A systematic literature review was conducted for randomised controlled trials that delivered additional physical rehabilitation for patients with critical illness during their acute hospital stay, assessed chronic disease burden, with a minimum follow-up period of 3 months measuring performance-based physical function and health-related quality of life outcomes. From 2178 records retrieved in the systematic literature review, four eligible trials were identified by two independent reviewers. Principal investigators of eligible trials were invited to contribute their data to this individual participant data meta-analysis. Risk of bias will be assessed (Cochrane risk of bias tool for randomised trials). Participant and trial characteristics, interventions and outcomes data of included studies will be summarised. Meta-analyses will entail a one-stage model, which will account for the heterogeneity across and the clustering between studies. Multiple imputation using chained equations will be used to account for the missing data. ETHICS AND DISSEMINATION: This individual participant data meta-analysis does not require ethical review as anonymised participant data will be used and no new data collected. Additionally, eligible trials were granted approval by institutional review boards or research ethics committees and informed consent was provided for participants. Data sharing agreements are in place permitting contribution of data. The study findings will be disseminated at conferences and through peer-reviewed publications. PROSPERO REGISTRATION NUMBER: CRD42019152526.


Asunto(s)
Enfermedad Crítica , Terapia por Ejercicio , Tiempo de Internación , Humanos , Enfermedad Crítica/rehabilitación , Calidad de Vida , Metaanálisis como Asunto , Revisiones Sistemáticas como Asunto
14.
Fed Pract ; 37(3): 114-124, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32317847

RESUMEN

INTRODUCTION: Diabetic foot ulcers (DFUs) are devastating, common, and costly. The mortality of veterans following a DFU is sobering with ulceration recognized as a significant marker of disease severity. Given the dramatic impact of diabetic foot complications to the veteran and the US health care system, the US Department of Veterans Affairs (VA) has long recognized the importance of preventive care for those at risk. Telemedicine has been suggested as a modality to reach veterans at high risk of chronic wound formation. OBSERVATIONS: The purpose of this review is to: (1) present the evidence supporting once-daily remote temperature monitoring (RTM), a telemedicine approach critical to improving both veteran access to care and diabetic foot outcomes; (2) summarize a 2017 study published by VA providers who have advanced clinical understanding of RTM; (3) present previously unpublished data from this study comparing high-risk VA and non-VA cohorts, highlighting the opportunity for additional focus on DFU prevention within the VA; and (4) report on recent VA use of a RTM technology based on this research, emphasizing lessons learned and best practices. CONCLUSIONS: There is a significant opportunity to shift diabetic foot care from treatment to prevention, improving veteran outcomes and reducing resource utilization. RTM is an evidence-based, recommended, but underused telemedicine solution that can catalyze this needed paradigm shift.

15.
Diabetes Res Clin Pract ; 164: 108158, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32333970

RESUMEN

AIM: FreeStyle Libre™ Flash Glucose Monitoring System (Flash GM), a novel, sensor-based, factory-calibrated system has been compared with self-monitoring of blood glucose in a well-controlled adult type 1 diabetes mellitus (T1D) population (HbA1c ≤ 7.5%, 58 mmol/mol), in a randomized controlled trial (RCT). The need for RCTs to recruit homogenous patients and for a well-controlled environment may not necessarily reflect use of a new technology in real clinical practice. METHODS: A random effects meta-analysis of all identified studies in T1D was performed to investigate changes in laboratory-measured HbA1c following introduction of Flash GM. RESULTS: Flash GM introduction showed a mean change from baseline to longest follow-up timepoint of -0.41% ([95% CI -0.51%, -0.31%]; P < 0.001; -4.5 [95% CI -5.6, -3.3] mmol/mol) in HbA1c in the random effects meta-analysis (34 studies comprising 5,466 participants). When the Flash GM arms of the two RCTs were excluded, there was a similar change in HbA1c of -0.41% ([95% CI -0.50%, -0.32%], P < 0.001; -4.5 [95% CI -5.4, -3.5] mmol/mol) in the 32 uncontrolled studies. Considerable heterogeneity was shown in all meta-analyses (I2 values > 85%), likely due to the inclusion of diverse populations and variations in study protocols, meaning random effects meta-analyses should be strongly preferred. CONCLUSIONS: In people with T1D, use of Flash GM for 2 to 24 months was associated with an estimated HbA1c reduction from baseline of 0.4%. A similar reduction occurred in uncontrolled studies where baseline HbA1c was generally higher compared with Flash GM arms of well-controlled studies.


Asunto(s)
Automonitorización de la Glucosa Sanguínea/métodos , Glucemia/metabolismo , Diabetes Mellitus Tipo 1/sangre , Hemoglobina Glucada/metabolismo , Adulto , Femenino , Hemoglobina Glucada/análisis , Humanos , Masculino , Persona de Mediana Edad
16.
Diabetes Res Clin Pract ; 161: 108074, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32109516

RESUMEN

AIMS: To assess the accuracy of once-daily foot temperature monitoring for predicting foot ulceration in diabetic patients with recent wounds and partial foot amputation, complications previously perceived as challenging. METHODS: We completed a planned analysis of existing data from a recent study in 129 participants with a previously-healed diabetic foot ulcer. We considered four cohorts: all participants, participants with partial foot amputation, participants with a recent wound, and participants without partial foot amputation and without a recent wound. We reported the prediction specificity, lead time, and annualized alert frequency in each cohort at maximum sensitivity. We assessed the two potentially challenging cohorts for non-inferior accuracy relative to the control cohort using Delong's method. RESULTS: We report non-inferior predictive accuracy in each of the two potentially-challenging cohorts relative to the control cohort (⍺ < 0.05). The alert lead time was similar across these cohorts, ranging from 33 to 42 days. CONCLUSIONS: Once-daily foot temperature monitoring is no less accurate for predicting foot ulceration in those with recent wounds and partial foot amputations than in those without these complications. These results support expanded practice of once-daily foot temperature monitoring, which may result in improved patient outcomes and reduced healthcare resource utilization.


Asunto(s)
Amputación Quirúrgica/métodos , Pie Diabético/diagnóstico , Úlcera del Pie/diagnóstico , Cicatrización de Heridas/fisiología , Anciano , Complicaciones de la Diabetes , Pie Diabético/cirugía , Femenino , Calor , Humanos , Masculino , Persona de Mediana Edad
17.
PLoS Biol ; 18(2): e3000610, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32108180

RESUMEN

Neo-sex chromosomes are found in many taxa, but the forces driving their emergence and spread are poorly understood. The female-specific neo-W chromosome of the African monarch (or queen) butterfly Danaus chrysippus presents an intriguing case study because it is restricted to a single 'contact zone' population, involves a putative colour patterning supergene, and co-occurs with infection by the male-killing endosymbiont Spiroplasma. We investigated the origin and evolution of this system using whole genome sequencing. We first identify the 'BC supergene', a broad region of suppressed recombination across nearly half a chromosome, which links two colour patterning loci. Association analysis suggests that the genes yellow and arrow in this region control the forewing colour pattern differences between D. chrysippus subspecies. We then show that the same chromosome has recently formed a neo-W that has spread through the contact zone within approximately 2,200 years. We also assembled the genome of the male-killing Spiroplasma, and find that it shows perfect genealogical congruence with the neo-W, suggesting that the neo-W has hitchhiked to high frequency as the male-killer has spread through the population. The complete absence of female crossing-over in the Lepidoptera causes whole-chromosome hitchhiking of a single neo-W haplotype, carrying a single allele of the BC supergene and dragging multiple non-synonymous mutations to high frequency. This has created a population of infected females that all carry the same recessive colour patterning allele, making the phenotypes of each successive generation highly dependent on uninfected male immigrants. Our findings show how hitchhiking can occur between the physically unlinked genomes of host and endosymbiont, with dramatic consequences.


Asunto(s)
Mariposas Diurnas/genética , Cromosomas de Insectos/genética , Cromosomas Sexuales/genética , Animales , Mariposas Diurnas/microbiología , Evolución Molecular , Femenino , Ligamiento Genético , Genoma/genética , Haplotipos , Masculino , Fenotipo , Spiroplasma/genética
18.
Ann Vasc Surg ; 65: 283.e7-283.e11, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31678543

RESUMEN

Aortocaval fistulas following endovascular repair of ruptured abdominal aortic aneurysms (rAAA) are rare. We herein describe repair using an Amplatzer Septal Occluder in a 68-year-old male who presented to the emergency department 6 months after ruptured endovascular aneurysm repair (rEVAR) with right heart failure. With the assistance of diagnostic angiography and intravascular ultrasound, the patient was found to have a 1.2 cm diameter aortocaval fistula and a type-II endoleak. His aortocaval fistula was successfully closed using an Amplatzer septal occluder device after failure of attempted closure with an Amplatzer plug and coiling of the aneurysm sac. His symptoms of heart failure improved, and he was discharged to an acute rehabilitation unit. Follow-up at 3 months demonstrated continued improvement in heart failure symptoms, and a small persistent type II endoleak. Aortocaval fistulae are a potentially fatal complication of rAAA. We discuss the sequelae and treatment strategies of aortocaval fistulas following rEVAR including the use of the Amplatzer Septal Occluder.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Rotura de la Aorta/cirugía , Fístula Arteriovenosa/terapia , Implantación de Prótesis Vascular/instrumentación , Procedimientos Endovasculares/instrumentación , Dispositivo Oclusor Septal , Vena Cava Inferior , Anciano , Aneurisma de la Aorta Abdominal/complicaciones , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Rotura de la Aorta/complicaciones , Rotura de la Aorta/diagnóstico por imagen , Fístula Arteriovenosa/diagnóstico por imagen , Fístula Arteriovenosa/etiología , Endofuga/etiología , Insuficiencia Cardíaca/etiología , Humanos , Masculino , Diseño de Prótesis , Resultado del Tratamiento , Vena Cava Inferior/diagnóstico por imagen
19.
Insects ; 10(9)2019 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-31505824

RESUMEN

Danaus chrysippus (L.), one of the world's commonest butterflies, has an extensive range throughout the Old-World tropics. In Africa it is divided into four geographical subspecies which overlap and hybridise freely in the East African Rift: Here alone a male-killing (MK) endosymbiont, Spiroplasma ixodetis, has invaded, causing female-biased populations to predominate. In ssp. chrysippus, inside the Rift only, an autosome carrying a colour locus has fused with the W chromosome to create a neo-W chromosome. A total of 40-100% of Rift females are neo-W and carry Spiroplasma, thus transmitting a linked, matrilineal neo-W, MK complex. As neo-W females have no sons, half the mother's genes are lost in each generation. Paradoxically, although neo-W females have no close male relatives and are thereby forced to outbreed, MK restricts gene flow between subspecies and may thus promote speciation. The neo-W chromosome originated in the Nairobi region around 2.2 k years ago and subsequently spread throughout the Rift contact zone in some 26 k generations, possibly assisted by not having any competing brothers. Our work on the neo-W chromosome, the spread of Spiroplasma and possible speciation is ongoing.

20.
Thorax ; 74(8): 787-796, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31048509

RESUMEN

BACKGROUND: Lung cancer is associated with poor health-related quality of life (HRQoL) and high symptom burden. This trial aimed to assess the efficacy of home-based rehabilitation versus usual care in inoperable lung cancer. METHODS: A parallel-group, assessor-blinded, allocation-concealed, randomised controlled trial. Eligible participants were allocated (1:1) to usual care (UC) plus 8 weeks of aerobic and resistance exercise with behaviour change strategies and symptom support (intervention group (IG)) or UC alone. Assessments occurred at baseline, 9 weeks and 6 months. The primary outcome, change in between-group 6 min walk distance (6MWD), was analysed using intention-to-treat (ITT). Subsequent analyses involved modified ITT (mITT) and included participants with at least one follow-up outcome measure. Secondary outcomes included HRQoL and symptoms. RESULTS: Ninety-two participants were recruited. Characteristics of participants (UC=47, IG=45): mean (SD) age 64 (12) years; men 55%; disease stage n (%) III=35 (38) and IV=48 (52); radical treatment 46%. There were no significant between-group differences for the 6MWD (n=92) at 9 weeks (p=0.308) or 6 months (p=0.979). The mITT analyses of 6MWD between-group differences were again non-significant (mean difference (95% CI): 9 weeks: -25.4 m (-64.0 to 13.3), p=0.198 and 6 months: 41.3 m (-26.7 to 109.4), p=0.232). Significant 6-month differences, favouring the IG, were found for HRQoL (Functional Assessment of Cancer Therapy-Lung: 13.0 (3.9 to 22.1), p=0.005) and symptom severity (MD Anderson Symptom Inventory-Lung Cancer: -2.2 (-3.6 to -0.9), p=0.001). CONCLUSIONS: Home-based rehabilitation did not improve functional exercise capacity but there were improvements in patient-reported exploratory secondary outcomes measures observed at 6 months. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ACTRN12614001268639).


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/rehabilitación , Terapia por Ejercicio/métodos , Ejercicio Físico , Neoplasias Pulmonares/rehabilitación , Anciano , Carcinoma de Pulmón de Células no Pequeñas/fisiopatología , Contraindicaciones de los Procedimientos , Tolerancia al Ejercicio , Femenino , Humanos , Neoplasias Pulmonares/fisiopatología , Masculino , Persona de Mediana Edad , Calidad de Vida , Entrenamiento de Fuerza , Autocuidado , Método Simple Ciego , Tasa de Supervivencia , Evaluación de Síntomas , Prueba de Paso
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...