Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 98
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Mol Biol Evol ; 41(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38401262

RESUMO

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.


Assuntos
Mimetismo Biológico , Borboletas , Animais , Borboletas/genética , Elementos de DNA Transponíveis , Mimetismo Biológico/genética , Fenótipo , África , Asas de Animais/anatomia & histologia
2.
PLoS Biol ; 18(2): e3000610, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32108180

RESUMO

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.


Assuntos
Borboletas/genética , Cromossomos de Insetos/genética , Cromossomos Sexuais/genética , Animais , Borboletas/microbiologia , Evolução Molecular , Feminino , Ligação Genética , Genoma/genética , Haplótipos , Masculino , Fenótipo , Spiroplasma/genética
3.
Biol Lett ; 18(6): 20210639, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35642381

RESUMO

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.


Assuntos
Borboletas , Pigmentação , Adaptação Biológica , Animais , Evolução Biológica , Borboletas/genética , Ciência do Cidadão , Frequência do Gene , Fenótipo , Comportamento Predatório , Seleção Genética
4.
Circulation ; 142(14): 1330-1338, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33017209

RESUMO

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.


Assuntos
Ponte de Artéria Coronária , Artéria Torácica Interna , Mortalidade , Artéria Radial , Grau de Desobstrução Vascular , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
5.
Thorax ; 76(7): 656-663, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33323480

RESUMO

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.


Assuntos
Estado Terminal/reabilitação , Estimulação Elétrica/métodos , Terapia por Exercício/métodos , Unidades de Terapia Intensiva , Força Muscular/fisiologia , Qualidade de Vida , Respiração Artificial/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego
6.
Chem Senses ; 45(8): 635-644, 2020 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-32866968

RESUMO

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.


Assuntos
Hidrocarbonetos/análise , Odorantes/análise , Animais , Formigas , Volatilização
7.
Ann Vasc Surg ; 65: 283.e7-283.e11, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31678543

RESUMO

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.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/cirurgia , Fístula Arteriovenosa/terapia , Implante de Prótese Vascular/instrumentação , Procedimentos Endovasculares/instrumentação , Dispositivo para Oclusão Septal , Veia Cava Inferior , Idoso , Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Ruptura Aórtica/complicações , Ruptura Aórtica/diagnóstico por imagem , Fístula Arteriovenosa/diagnóstico por imagem , Fístula Arteriovenosa/etiologia , Endoleak/etiologia , Insuficiência Cardíaca/etiologia , Humanos , Masculino , Desenho de Prótese , Resultado do Tratamento , Veia Cava Inferior/diagnóstico por imagem
8.
Thorax ; 74(8): 787-796, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31048509

RESUMO

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).


Assuntos
Carcinoma Pulmonar de Células não Pequenas/reabilitação , Terapia por Exercício/métodos , Exercício Físico , Neoplasias Pulmonares/reabilitação , Idoso , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Contraindicações de Procedimentos , Tolerância ao Exercício , Feminino , Humanos , Neoplasias Pulmonares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Treinamento Resistido , Autocuidado , Método Simples-Cego , Taxa de Sobrevida , Avaliação de Sintomas , Teste de Caminhada
9.
Thorax ; 74(3): 282-290, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30538163

RESUMO

RATIONALE: Highly prevalent and severe sleep-disordered breathing caused by acute cervical spinal cord injury (quadriplegia) is associated with neurocognitive dysfunction and sleepiness and is likely to impair rehabilitation. OBJECTIVE: To determine whether 3 months of autotitrating CPAP would improve neurocognitive function, sleepiness, quality of life, anxiety and depression more than usual care in acute quadriplegia. METHODS AND MEASUREMENTS: Multinational, randomised controlled trial (11 centres) from July 2009 to October 2015. The primary outcome was neurocognitive (attention and information processing as measure with the Paced Auditory Serial Addition Task). Daytime sleepiness (Karolinska Sleepiness Scale) was a priori identified as the most important secondary outcome. MAIN RESULTS: 1810 incident cases were screened. 332 underwent full, portable polysomnography, 273 of whom had an apnoea hypopnoea index greater than 10. 160 tolerated at least 4 hours of CPAP during a 3-day run-in and were randomised. 149 participants (134 men, age 46±34 years, 81±57 days postinjury) completed the trial. CPAP use averaged 2.9±2.3 hours per night with 21% fully 'adherent' (at least 4 hours use on 5 days per week). Intention-to-treat analyses revealed no significant differences between groups in the Paced Auditory Serial Addition Task (mean improvement of 2.28, 95% CI -7.09 to 11.6; p=0.63). Controlling for premorbid intelligence, age and obstructive sleep apnoea severity (group effect -1.15, 95% CI -10 to 7.7) did not alter this finding. Sleepiness was significantly improved by CPAP on intention-to-treat analysis (mean difference -1.26, 95% CI -2.2 to -0.32; p=0.01). CONCLUSION: CPAP did not improve Paced Auditory Serial Addition Task scores but significantly reduced sleepiness after acute quadriplegia. TRIAL REGISTRATION NUMBER: ACTRN12605000799651.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Quadriplegia/complicações , Síndromes da Apneia do Sono/terapia , Traumatismos da Medula Espinal/complicações , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Quadriplegia/psicologia , Qualidade de Vida , Síndromes da Apneia do Sono/diagnóstico , Síndromes da Apneia do Sono/etiologia , Traumatismos da Medula Espinal/psicologia , Fatores de Tempo , Resultado do Tratamento
10.
Cytogenet Genome Res ; 153(1): 46-53, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29130975

RESUMO

The number of sequenced lepidopteran genomes is increasing rapidly. However, the corresponding assemblies rarely represent whole chromosomes and generally also lack the highly repetitive W sex chromosome. Knowledge of the karyotypes can facilitate genome assembly and further our understanding of sex chromosome evolution in Lepidoptera. Here, we describe the karyotypes of the Glanville fritillary Melitaea cinxia (n = 31), the monarch Danaus plexippus (n = 30), and the African queen D. chrysippus (2n = 60 or 59, depending on the source population). We show by FISH that the telomeres are of the (TTAGG)n type, as found in most insects. M. cinxia and D. plexippus have "conventional" W chromosomes which are heterochromatic in meiotic and somatic cells. In D. chrysippus, the W is inconspicuous. Neither telomeres nor W chromosomes are represented in the published genomes of M. cinxia and D. plexippus. Representation analysis in sequenced female and male D. chrysippus genomes detected an evolutionarily old autosome-Z chromosome fusion in Danaus. Conserved synteny of whole chromosomes, so called "macro synteny", in Lepidoptera permitted us to identify the chromosomes involved in this fusion. An additional and more recent sex chromosome fusion was found in D. chrysippus by karyotype analysis and classical genetics. In a hybrid population between 2 subspecies, D. c. chrysippus and D. c. dorippus, the W chromosome was fused to an autosome that carries a wing colour locus. Thus, cytogenetics and the present state of genome data complement one another to reveal the evolutionary history of the species.


Assuntos
Borboletas/genética , Genoma/genética , Cariótipo , Sintenia/genética , Telômero/genética , Animais , Mapeamento Cromossômico , Cromossomos/classificação , Cromossomos/genética , Feminino , Hibridização in Situ Fluorescente , Masculino
11.
BMC Cancer ; 17(1): 663, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-28962608

RESUMO

BACKGROUND: Lung cancer is one of the most commonly diagnosed cancers, and is a leading cause of cancer mortality world-wide. Due to lack of early specific symptoms, the majority of patients present with advanced, inoperable disease and five-year relative survival across all stages of non-small cell lung cancer (NSCLC) is 14%. People with lung cancer also report higher levels of symptom distress than those with other forms of cancer. Several benefits for survival and patient reported outcomes are reported from physical activity and exercise in other tumour groups. We report the protocol for a study investigating the benefits of exercise, behaviour change and symptom self-management for patients with recently diagnosed, inoperable, NSCLC. METHODS: This multi-site, parallel-group, assessor-blinded randomised controlled trial, powered for superiority, aims to assess functional and patient-reported outcomes of a multi-disciplinary, home-based exercise and supportive care program for people commencing treatment. Ninety-two participants are being recruited from three tertiary-care hospitals in Melbourne, Australia. Following baseline testing, participants are randomised using concealed allocation, to receive either: a) 8 weeks of home-based exercise (comprising an individualised endurance and resistance exercise program and behaviour change coaching) and nurse-delivered symptom self-management intervention or b) usual care. The primary outcome is the between-group difference in the change in functional exercise capacity (six-minute walk distance) from baseline to post-program assessment. Secondary outcomes include: objective and self-reported physical activity levels, physical activity self-efficacy, behavioural regulation of motivation to exercise and resilience, muscle strength (quadriceps and grip), health-related quality of life, anxiety and depression and symptom interference. DISCUSSION: There is a lack of evidence regarding the benefit of exercise intervention for people with NSCLC, particularly in those with inoperable disease receiving treatment. This trial will contribute to evidence currently being generated in national and international trials by implementing and evaluating a home-based program including three components not yet combined in previous research, for people with inoperable NSCLC receiving active treatment and involving longer-term follow-up of outcomes. This trial is ongoing and currently recruiting. TRIAL REGISTRATION: This trial was prospectively registered on the Australian New Zealand Clinical Trials Registry ( ACTRN12614001268639 : (4/12/14).


Assuntos
Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Terapia por Exercício , Adolescente , Adulto , Idoso , Austrália/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Carcinoma Pulmonar de Células não Pequenas/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Força Muscular/fisiologia , Qualidade de Vida , Autocuidado , Centros de Atenção Terciária
12.
Int Wound J ; 14(1): 198-202, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27212250

RESUMO

Current embodiments of negative pressure wound therapy (NPWT) create a hermetically sealed chamber at the surface of the body using polyurethane foam connected to a vacuum pump, which is then covered by a flexible adhesive drape. Commercially available NPWT systems routinely use flexible polyethylene films that have a sticky side, coated with the same acrylate adhesives used in other medical devices such as ECG leads and grounding pads. Severe reactions to the acrylate adhesives in these other devices, although uncommon, have been reported. We describe the case of a 63-year-old woman with an intractable leg ulcer resulting from external-beam radiotherapy (XRT). Treatment with a standard commercial NPWT system induced severe inflammation of the skin in direct contact with drape adhesive. We successfully administered prolonged, outpatient NPWT to the patient using an alternative method (first described by Bagautdinov in 1986), using plain polyethylene film and petrolatum. The necessary hermetic seal is achieved by smearing the skin with petrolatum before applying the polyethylene film and activating the vacuum pump. The Bagautdinov method is a practical solution to the problem of adapting NPWT to patients with contact sensitivity or skin tears related to the adhesive compounds in the flexible drapes. Its use of a circumferential elastic wrap to maintain constant pressure on the seal probably limits the Bagautdinov technique to the extremities.


Assuntos
Acrilatos/efeitos adversos , Adesivos/efeitos adversos , Bandagens/efeitos adversos , Hipersensibilidade , Inflamação/etiologia , Tratamento de Ferimentos com Pressão Negativa/métodos , Vaselina/uso terapêutico , Feminino , Humanos , Inflamação/terapia , Úlcera da Perna/terapia , Pessoa de Meia-Idade , Resultado do Tratamento , Cicatrização
13.
Proc Biol Sci ; 283(1835)2016 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-27440667

RESUMO

Sexually antagonistic selection can drive both the evolution of sex chromosomes and speciation itself. The tropical butterfly the African Queen, Danaus chrysippus, shows two such sexually antagonistic phenotypes, the first being sex-linked colour pattern, the second, susceptibility to a male-killing, maternally inherited mollicute, Spiroplasma ixodeti, which causes approximately 100% mortality in male eggs and first instar larvae. Importantly, this mortality is not affected by the infection status of the male parent and the horizontal transmission of Spiroplasma is unknown. In East Africa, male-killing of the Queen is prevalent in a narrow hybrid zone centred on Nairobi. This hybrid zone separates otherwise allopatric subspecies with different colour patterns. Here we show that a neo-W chromosome, a fusion between the W (female) chromosome and an autosome that controls both colour pattern and male-killing, links the two phenotypes thereby driving speciation across the hybrid zone. Studies of the population genetics of the neo-W around Nairobi show that the interaction between colour pattern and male-killer susceptibility restricts gene flow between two subspecies of D. chrysippus Our results demonstrate how a complex interplay between sex, colour pattern, male-killing, and a neo-W chromosome, has set up a genetic 'sink' that keeps the two subspecies apart. The association between the neo-W and male-killing thus provides a 'smoking gun' for an ongoing speciation process.


Assuntos
Borboletas/genética , Especiação Genética , Pigmentação/genética , Cromossomos Sexuais/genética , Animais , Cor , Feminino , Fluxo Gênico , Genética Populacional , Quênia , Masculino , Fenótipo
14.
Ann Vasc Surg ; 33: 120-5, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26965804

RESUMO

BACKGROUND: Arteriovenous access dysfunction is commonly caused by venous outflow stenosis, leading to thrombosis of the conduit. Given that there are limited lifetime hemodialysis access sites, the preservation of existing sites through novel means is of high priority. This study compares the efficacy of balloon angioplasty and stent placement to surgical patch angioplasty for upper arm (brachium) thrombosed or dysfunctional hemodialysis access sites in a group of patients at a single institution. METHODS: Using the operating room log and electronic medical record system, we retrospectively examined the outcomes of 52 consecutive patients (3 were lost to follow-up), who had either stent placement (34 patients) or patch angioplasty (15 patients) for hemodialysis access salvage to calculate postintervention patency. RESULTS: Initial postinterventional patency (PIP1) for patch angioplasty compared with stent placement was not statistically significant at any time during a mean 6-month follow-up (60% vs. 67.65% at 1 month, 33.33% vs. 41.18% at 3 months, and 13.33% vs. 17.65% at 6 months, respectively; P = 0.75). Patency after secondary reintervention (PIP2) was longer for patients who had stent placement as the initial intervention (n = 15) than patients who had patch angioplasty (n = 5; 100% vs. 80% at 1 month, 66.68% vs. 80% at 3 months, and 46.67% vs. 40% at 6 months, respectively), but again there was no statistically significant difference between the 2 groups (P = 0.84). At last, the initial PIP1 of arteriovenous fistula (AVF) and arteriovenous graft (AVG) salvaged before occlusion was significantly different from that of occluded access sites (40% vs. 10% at 6 months, P = 0.024). CONCLUSIONS: Our data suggest that AVF had a longer postinterventional primary patency than AVG though the difference did not reach statistical significance. Stents extended PIP1 for the thrombosed or failing arteriovenous access longer than patch angioplasty, but the difference was not statistically significant. Patency is longer if intervention is made before graft thrombosis. Our data also indicate better prolongation of patency with a second reintervention (PIP2) if the first intervention was a stent placement. Patch angioplasty appears to be a less attractive alternative for correction of venous outflow stenosis given the more invasive and occasionally technically difficult procedure.


Assuntos
Angioplastia com Balão/instrumentação , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Oclusão de Enxerto Vascular/terapia , Diálise Renal , Stents , Trombose/terapia , Extremidade Superior/irrigação sanguínea , Idoso , Angioplastia com Balão/efeitos adversos , Angioplastia com Balão/métodos , Registros Eletrônicos de Saúde , Feminino , Oclusão de Enxerto Vascular/diagnóstico por imagem , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas de Informação em Salas Cirúrgicas , Reoperação , Estudos Retrospectivos , Trombose/diagnóstico por imagem , Trombose/etiologia , Trombose/fisiopatologia , Resultado do Tratamento , Grau de Desobstrução Vascular
15.
BMC Public Health ; 16(Suppl 3): 1062, 2016 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-28185562

RESUMO

BACKGROUND: The Australian Longitudinal Study on Male Health (Ten to Men) used a complex sampling scheme to identify potential participants for the baseline survey. This raises important questions about when and how to adjust for the sampling design when analyzing data from the baseline survey. METHODS: We describe the sampling scheme used in Ten to Men focusing on four important elements: stratification, multi-stage sampling, clustering and sample weights. We discuss how these elements fit together when using baseline data to estimate a population parameter (e.g., population mean or prevalence) or to estimate the association between an exposure and an outcome (e.g., an odds ratio). We illustrate this with examples using a continuous outcome (weight in kilograms) and a binary outcome (smoking status). RESULTS: Estimates of a population mean or disease prevalence using Ten to Men baseline data are influenced by the extent to which the sampling design is addressed in an analysis. Estimates of mean weight and smoking prevalence are larger in unweighted analyses than weighted analyses (e.g., mean = 83.9 kg vs. 81.4 kg; prevalence = 18.0 % vs. 16.7 %, for unweighted and weighted analyses respectively) and the standard error of the mean is 1.03 times larger in an analysis that acknowledges the hierarchical (clustered) structure of the data compared with one that does not. For smoking prevalence, the corresponding standard error is 1.07 times larger. Measures of association (mean group differences, odds ratios) are generally similar in unweighted or weighted analyses and whether or not adjustment is made for clustering. CONCLUSIONS: The extent to which the Ten to Men sampling design is accounted for in any analysis of the baseline data will depend on the research question. When the goals of the analysis are to estimate the prevalence of a disease or risk factor in the population or the magnitude of a population-level exposure-outcome association, our advice is to adopt an analysis that respects the sampling design.


Assuntos
Métodos Epidemiológicos , Saúde do Homem , Obesidade/epidemiologia , Projetos de Pesquisa , Fumar/epidemiologia , Adulto , Austrália , Peso Corporal , Criança , Análise por Conglomerados , Humanos , Estudos Longitudinais , Masculino , Prevalência , Fatores de Risco , Inquéritos e Questionários
16.
BMC Public Health ; 16(Suppl 3): 1030, 2016 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-28185550

RESUMO

BACKGROUND: The Australian Longitudinal Study on Male Health (Ten to Men) was established in 2011 to build the evidence base on male health to inform policy and program development. METHODS: Ten to Men is a national longitudinal study with a stratified multi-stage cluster random sample design and oversampling in rural and regional areas. Household recruitment was conducted from October 2013 to July 2014. Males who were aged 10 to 55 years residing in private dwellings were eligible to participate. Data were collected via self-completion paper questionnaires (participants aged 15 to 55) and by computer-assisted personal interview (boys aged 10 to 14). Household and proxy health data for boys were collected from a parent via a self-completion paper-based questionnaire. Questions covered socio-demographics, health status, mental health and wellbeing, health behaviours, social determinants, and health knowledge and service use. RESULTS: A cohort of 15,988 males aged between 10 and 55 years was recruited representing a response fraction of 35 %. CONCLUSION: Ten to Men is a unique resource for investigating male health and wellbeing. Wave 1 data are available for approved research projects.


Assuntos
Nível de Saúde , Saúde do Homem , Adolescente , Adulto , Austrália , Criança , Características da Família , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Estudos Longitudinais , Masculino , Saúde Mental , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , População Rural , Determinantes Sociais da Saúde , Inquéritos e Questionários , Adulto Jovem
17.
Chron Respir Dis ; 12(2): 146-54, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25749346

RESUMO

The 6-minute walk distance (6MWD) is one of the most commonly used measures of functional capacity in lung cancer, however, the minimal important difference (MID) has not been established. The aims of this exploratory study are, in lung cancer, to estimate (1) the MID of the 6MWD and (2) relationship between 6MWD, demographic and disease-related factors. Fifty-six participants with stage I-IV lung cancer completed the 6MWD prior to treatment and 10 weeks later. No exercise intervention occurred. Additional measures included European Organization for Research and Treatment of Cancer questionnaire (EORTC-QLQ-C30) and questionnaires assessing function, physical activity and symptoms. MID was calculated using anchor- and distribution-based methods. The mean 6MWD decline in participants classed as deteriorated was 60 m compared with 16 m in participants classed as not-deteriorated (p = 0.01). The receiver operating curve indicated a cut-off value for clinically relevant change to be 42 m (95% confidence interval (CI) 6-75) (area under curve = 0.66, 95% CI 0.51-0.81) or a 9.5% change. Distribution-based methods indicated an MID between 22 m (95% CI 18-26) and 32 m (95% CI 20-42). Higher 6MWD correlated with better function (r = -0.42, p = 0.001), physical activity (r = 0.56, p < 0.005) and dyspnoea (r = -0.44, p = 0.001). The MID for deterioration of the 6MWD in lung cancer is estimated to be between 22 m and 42 m or a change of 9.5%.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Teste de Esforço/métodos , Neoplasias Pulmonares/fisiopatologia , Caminhada , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/terapia , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC
18.
Ann Vasc Surg ; 28(6): 1513-21, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24561209

RESUMO

BACKGROUND: The vasodilator cilostazol (Pletal(®)), a phosphodiesterase-3 inhibitor, is approved in the United States for treatment of intermittent claudication. This study was aimed at evaluating its efficacy as an adjunct in the management of arterial ulceration. METHODS: The clinical records of patients treated with cilostazol from 2000 to 2010 at one institution were obtained. Of the 561 patients treated with cilostazol, we identified 82 (101 limbs) who started on therapy only after wounds were present and whose records were sufficient to assess healing. Only if all wounds in a limb completely healed without intervening arterial reconstruction, amputation, primary closure, or skin grafting, the limb was deemed healed with the assistance of cilostazol. With bilateral involvement, both limbs had to heal for the patient to be judged healed. Subjects who were lost to follow-up, died, or underwent surgical interventions other than debridement were deemed failures. Age, weight, height, body mass index (BMI), creatinine, diabetes, insulin therapy, hemodialysis, smoking history, congestive heart failure, cilostazol dose, and length of therapy were compared, as well as, the number of wounds, size of largest wound, chronicity, ankle-brachial index, the presence of exposed bone/tendon/joint, or the presence of gangrene. RESULTS: Overall 30 of 82 patients (36.6%) and 41 of 101 (40.6%) limbs were deemed healed without surgical intervention or revascularization (open or endovascular). When 9 limbs that healed after skin grafts (n = 2) or foot-sparing amputations (n = 7) but without revascularization were considered, the overall rate of lower extremity limb salvage was 50.5%. Demographic characteristics were similar in the 2 groups except healed patients tended to be taller and weigh more but had similar BMI. The incidence of diabetes was higher in nonhealed limbs (73.3% vs. 50.0%, P = 0.0587). Gangrene was less common in healed patients (22.6% vs. 49.1%, P = 0.059) and healed limbs (22.0% vs. 48.3%, P = 0.027). Most subjects received 200 mg of cilostazol daily (healed:177 ± 53 mg vs. nonhealed: 172 ± 47 mg). Mean length of therapy in healed patients was 278 ± 302 days compared with 108 ± 129 days in nonhealed subjects before discontinuation of drug therapy or surgery, death, or loss to follow-up intervened. CONCLUSIONS: The observed limb healing rate with cilostazol compares favorably to the ~20% rate observed in subjects treated with placebo in multicenter trials of another vasodilator, iloprost. Although gangrene and diabetes correlate with lower prospects for healing, our data suggest that cilostazol helps promote healing of wounds when arterial insufficiency is present.


Assuntos
Úlcera da Perna/tratamento farmacológico , Extremidade Inferior/irrigação sanguínea , Doença Arterial Periférica/tratamento farmacológico , Inibidores da Fosfodiesterase 3/uso terapêutico , Tetrazóis/uso terapêutico , Extremidade Superior/irrigação sanguínea , Vasodilatadores/uso terapêutico , Cicatrização/efeitos dos fármacos , Idoso , Cilostazol , Esquema de Medicação , Feminino , Humanos , Úlcera da Perna/diagnóstico , Salvamento de Membro , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico , Inibidores da Fosfodiesterase 3/administração & dosagem , Estudos Retrospectivos , Tetrazóis/administração & dosagem , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Vasodilatadores/administração & dosagem
19.
Ann Vasc Surg ; 28(4): 831-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24361383

RESUMO

BACKGROUND: Standard surveillance after endovascular abdominal aortic aneurysm repair (EVAR) consists of periodic computed tomographic arteriographies (CTAs) usually performed at postoperative months 1, 6, and 12, and then annually. This imaging regimen is expensive and exposes patients to the hazards of radiation and intravenous contrast. We hypothesized that a normal 1-month CTA after EVAR with no endoleak or other significant abnormality predicts a low rate of future complications, which would justify a reduction in frequency of subsequent CTAs. METHODS: We identified 106 consecutive patients who underwent EVAR at a single hospital from 2003 to 2010 and reviewed all their CTAs. Fifteen patients for whom we could not review a postoperative CTA were excluded. Of the remaining 91 patients, 70 (76.9%) had no abnormality on their CTA at 1 month after EVAR. The medical records of these 70 patients were analyzed for subsequent complications and interventions related to EVAR. RESULTS: The mean patient follow-up was 3.4 ± 2.1 years. Five of the 70 (7.1%) patients with a normal post-EVAR CTA developed late complications consisting of 1 type I endoleak, 3 type II endoleaks, and 1 case of endotension. Only the type I endoleak and one of the type II endoleaks met criteria for intervention, and in both cases, the endoleaks were discovered >3 years after EVAR. Log-rank test showed a statistically significant increased freedom from aneurysm sac expansion in patients with a normal compared with an abnormal 1-month CTA (P < 0.001). CONCLUSIONS: For patients who have a normal CTA with no endoleak 1 month after EVAR, it is reasonable to consider less-frequent CTA surveillance because no significant complications requiring intervention occurred before 3 years. This would decrease unnecessary CTAs and health care expenditures as well as minimize patient exposure to radiation and intravenous contrast.


Assuntos
Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/cirurgia , Aortografia/métodos , Implante de Prótese Vascular/efeitos adversos , Endoleak/diagnóstico por imagem , Procedimentos Endovasculares/efeitos adversos , Tomografia Computadorizada por Raios X , Idoso , Idoso de 80 Anos ou mais , Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aortografia/efeitos adversos , California , Intervalo Livre de Doença , Endoleak/terapia , Humanos , Estimativa de Kaplan-Meier , Masculino , Seleção de Pacientes , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Tomografia Computadorizada por Raios X/efeitos adversos , Resultado do Tratamento , Procedimentos Desnecessários
20.
Ecol Evol ; 14(2): e11024, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38414566

RESUMO

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.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA