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1.
BMC Genomics ; 23(1): 321, 2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35459090

RESUMEN

BACKGROUND: Previous phylogeographic studies of the lion (Panthera leo) have improved our insight into the distribution of genetic variation, as well as a revised taxonomy which now recognizes a northern (Panthera leo leo) and a southern (Panthera leo melanochaita) subspecies. However, existing whole range phylogeographic studies on lions either consist of very limited numbers of samples, or are focused on mitochondrial DNA and/or a limited set of microsatellites. The geographic extent of genetic lineages and their phylogenetic relationships remain uncertain, clouded by massive sampling gaps, sex-biased dispersal and incomplete lineage sorting. RESULTS: In this study we present results of low depth whole genome sequencing and subsequent variant calling in ten lions sampled throughout the geographic range, resulting in the discovery of >150,000 Single Nucleotide Polymorphisms (SNPs). Phylogenetic analyses revealed the same basal split between northern and southern populations, as well as four population clusters on a more local scale. Further, we designed a SNP panel, including 125 autosomal and 14 mitochondrial SNPs, which was tested on >200 lions from across their range. Results allow us to assign individuals to one of these four major clades (West & Central Africa, India, East Africa, or Southern Africa) and delineate these clades in more detail. CONCLUSIONS: The results presented here, particularly the validated SNP panel, have important applications, not only for studying populations on a local geographic scale, but also for tracing samples of unknown origin for forensic purposes, and for guiding conservation management of ex situ populations. Thus, these genomic resources not only contribute to our understanding of the evolutionary history of the lion, but may also play a crucial role in conservation efforts aimed at protecting the species in its full diversity.


Asunto(s)
Leones , Panthera , Animales , Variación Genética , Humanos , Leones/genética , Panthera/genética , Filogenia , Polimorfismo de Nucleótido Simple , Secuenciación Completa del Genoma
2.
Med Educ ; 56(3): 339-348, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34862660

RESUMEN

Despite the increasing numbers of women students in medical schools, focused attention on their perceptions about medical school and the medical profession remain underexamined. These perceptions are important to understand, particularly since women students are likely burdened with a host of gender norms related to work, family, and their future roles as physicians. Early experiences in medical school offer important insights into the larger student experience and are tied to academic outcomes and feelings of belonging. To examine early experiences of women medical students, this qualitative study used sensemaking theory to describe the current context and "story" of ideal worker norms. Critical qualitative interviews of 38 women students were performed during their first 2 months of medical school and explored both how the students perceived and experienced ideal worker norms, and how they made sense of the "story" of ideal worker norms. The participants described ways they encountered gendering and ideal worker norms through displays of nurturing behaviour, expectations to balance a future family, and whether they looked or acted the part of a doctor. This article highlights the challenges women medical students are already aware they will face, the opportunities they look forward to, and the strengths they anticipate leaning on to navigate their profession. Results from this study have implications for women medical students' learning experiences and transitions into medical school and for faculty, staff, and scholars concerned with challenging gendering norms that shape medical education.


Asunto(s)
Educación Médica , Médicos , Estudiantes de Medicina , Femenino , Humanos , Investigación Cualitativa , Facultades de Medicina
3.
Osteoarthritis Cartilage ; 29(12): 1673-1681, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33878493

RESUMEN

OBJECTIVE: To evaluate if returning to pivoting sport following anterior cruciate ligament reconstruction (ACLR) is associated with longitudinal structural and symptomatic osteoarthritis outcomes. DESIGN: Eighty-one adults aged 18-50 years were followed prospectively 1- to 5-years post-ACLR. Return to pivoting sport was assessed at 1-, 3- and 5-years. Longitudinal changes in osteoarthritis features were evaluated from 1- and 5-year magnetic resonance imaging (MRI)s using MRI Osteoarthritis Knee Score (MOAKS). Radiographic osteoarthritis and self-reported knee symptoms, function and quality of life were assessed using the Osteoarthritis Research Society International (OARSI) atlas and Knee injury Osteoarthritis Outcome Score (KOOS), respectively, at 5 years post-ACLR. Generalised linear models (adjusted for baseline characteristics) assessed whether returning to pivoting sport was associated with risk of worsening osteoarthritis features on MRI, radiographic osteoarthritis and KOOS. RESULTS: Thirty participants returned to pivoting sport 1-year post-ACLR and 50 returned at any time (i.e., 1-, 3- or 5-years). Returning to pivoting sport was not associated with worsening of any MRI osteoarthritis feature (risk ratio (RR) range: 0.59-2.91) or 5-year KOOS (ß range: -2.73-3.69). Returning to pivoting sport at 1-year and up to 5-years post-ACLR was associated with a 50% (RR 0.49, 95%CI 0.10-2.37) and 40% (RR 0.60, 95%CI 0.16-2.17) reduced risk of radiographic osteoarthritis, respectively, but these risk reductions were inconclusive due to wide confidence intervals. CONCLUSION: After ACLR, returning to pivoting sport was not associated with increased risk of worsening knee osteoarthritis features on MRI, radiographic osteoarthritis or knee symptoms. Participation in pivoting sport need not be avoided as part of osteoarthritis secondary prevention strategies.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior , Osteoartritis de la Rodilla/prevención & control , Volver al Deporte , Prevención Secundaria , Adolescente , Adulto , Lesiones del Ligamento Cruzado Anterior/cirugía , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/diagnóstico por imagen , Radiografía , Adulto Joven
4.
Acta Psychiatr Scand ; 142(4): 337-347, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32307692

RESUMEN

OBJECTIVE: To compare the gut microbiome profile (by way of taxon analysis and indices of ß- and α-diversity) and inflammatory markers (C-reactive protein [CRP], interleukin-6[IL-6] and tumour necrosis factor-α [TNF-α]) of obsessive-compulsive disorder (OCD) outpatients and non-psychiatric community controls. METHODS: We collected morning stool and blood samples from 21 non-depressed, medication-free OCD patients and 22 age- and sex-matched non-psychiatric community controls. Microbiota analysis was performed using Illumina sequencing of the V3 region of 16S rRNA; serum CRP samples were analysed using immunoturbidimetry and plasma IL-6/TNF-α were examined by high-sensitivity ELISA. Multiple comparisons were corrected for using the false discovery rate (α = 0.05). RESULTS: Compared to controls, the OCD group presented lower species richness/evenness (α-diversity, Inverse Simpson) and lower relative abundance of three butyrate producing genera (Oscillospira, Odoribacter and Anaerostipes). Compared to controls, mean CRP, but not IL-6 and TNF-α, was elevated OCD patients. CRP revealed moderate to strong associations with psychiatric symptomatology. CONCLUSION: To our knowledge, this is the first investigation of the gut microbiome in OCD. In addition, our findings lend further support for the potential association of inflammation and OCD. These results suggest the gut microbiome may be a potential pathway of interest for future OCD research.


Asunto(s)
Microbioma Gastrointestinal , Trastorno Obsesivo Compulsivo , Humanos , Inflamación , Proyectos Piloto , ARN Ribosómico 16S/genética
5.
Br J Surg ; 103(13): 1823-1827, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27748963

RESUMEN

BACKGROUND: Surveillance is mandatory for all patients with a thoracic aortic aneurysm (TAA). The frequency of surveillance imaging, however, is not evidence-based, as few data exist regarding TAA growth rates. This study aimed to determine the rate of TAA expansion and to inform surveillance intervals based on TAA diameter. METHODS: Patients with a TAA for whom morphological data were available from serial CT scans were studied. Annualized growth rates based on diameter at presentation and time taken to reach a theoretical intervention threshold of 55 mm were calculated. The number of patients who would have achieved the threshold undetected was determined based on simulated imaging intervals of 6 months, 1, 2 and 3 years. RESULTS: A total of 2916 scans from 995 patients were analysed. The mean aortic expansion rate was 2·76 mm per year for all patients, with an exponential increase observed at sizes above 45 mm. Only 3·9 per cent of patients with a starting diameter of 30-39 mm and 5·3 per cent of those with a diameter of 40-44 mm achieved threshold size within 2 years. Conversely, the probability of expansion to more than 55 mm was 74·5 per cent in 2 years for patients with a starting diameter of 50-54 mm, rising to 85·7 per cent at 3 years. CONCLUSION: Based on a threshold of 55 mm for intervention, most patients with a maximum aortic diameter below 40 mm could safely undergo surveillance at 2-yearly intervals. Above 45 mm, annual surveillance is recommended. Patients with a diameter greater than 50 mm could be optimized for possible repair, if this is clinically appropriate.


Asunto(s)
Aneurisma de la Aorta Torácica/patología , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Angiografía por Tomografía Computarizada , Humanos , Estimación de Kaplan-Meier , Tamaño de los Órganos , Factores de Tiempo
6.
Br J Surg ; 103(7): 819-29, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27095350

RESUMEN

BACKGROUND: The fate of the aneurysm sac after thoracic endovascular aortic repair (TEVAR) remains poorly defined. The aim of this study was to characterize the incidence of aneurysm sac expansion after TEVAR, and to determine the effect of aneurysm morphology on postoperative sac behaviour. METHODS: Preoperative and postoperative CT angiography (CTA) images were analysed from a proprietary database (M2S). TEVARs undertaken for thoracic aortic aneurysms from 2004 to 2013 were included. Preoperative aortic morphology was available for each patient. Post-TEVAR sac expansion was defined as an increase in aortic diameter of at least 5 mm. The influence of aortic morphological variables on sac expansion was assessed using Cox regression and Kaplan-Meier analysis. RESULTS: CTA images were available for 899 patients who underwent TEVAR. Median follow-up was 2·1 (i.q.r. 1·7-2·4) years. Some 46·0 per cent had a maximum aneurysm diameter of 55 mm or more at the time of repair. The 5-year rate of freedom from sac expansion of at least 5 mm was 60·9 per cent. The sac expansion rate after 3 years was higher when the proximal sealing zone was over 38 mm in diameter (freedom from expansion 51·2 per cent versus 76·6 per cent for diameter 38 mm or less; P < 0·001), or 20 mm or less in length (freedom from expansion 67·3 per cent versus 77·1 per cent for length exceeding 20 mm; P = 0·022). Findings for the distal sealing zone were similar. The risk of sac expansion increased according to the number of adverse morphological risk factors (freedom from expansion rate 79·1 per cent at 3 years in patients with 2 or fewer risk factors versus 45·7 per cent in those with more than 2; P < 0·001). CONCLUSION: Sac expansion was common in this cohort of patients undergoing TEVAR for thoracic aortic aneurysm. Aneurysm sac expansion was significantly influenced by adverse morphological features in the aortic stent-graft sealing zones.


Asunto(s)
Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/métodos , Endofuga/etiología , Anciano , Prótesis Vascular , Angiografía por Tomografía Computarizada , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/métodos , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Periodo Preoperatorio , Factores de Riesgo , Stents
7.
Br J Surg ; 103(12): 1626-1633, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27704527

RESUMEN

BACKGROUND: Perioperative mortality is low for patients undergoing abdominal aortic aneurysm (AAA) repair, but long-term survival remains poor. Although patients diagnosed with AAA have a significant burden of cardiovascular disease and associated risk factors, there is limited understanding of the contribution of cardiovascular risk management to long-term survival. METHODS: General practice records within The Health Improvement Network (THIN) were examined. Patients with a diagnosis of AAA and at least 1 year of registered medical history were identified from 2000 to 2012. Medical therapies for cardiovascular risk were classified as antiplatelet, statin or antihypertensive agents. Progression to death was investigated using the G-computation formula with time-dependent co-variables to account for differences in exposure to cardiovascular risk-modifying treatments and the confounding between exposure, co-morbidities and death. RESULTS: Some 12 485 patients had a recorded diagnosis of AAA. From 2000 to 2012, prescription of medications that modify cardiovascular risk increased: from 26·6 to 76·7 per cent for statins, from 56·5 to 73·9 per cent for antiplatelet agents and from 75·3 to 84·0 per cent for antihypertensive drugs. Adjusted Kaplan-Meier curves demonstrated a better 5-year survival rate in patients receiving statins (68·4 versus 42·2 per cent), antiplatelet agents (63·6 versus 39·7 per cent) or antihypertensive agents (61·5 versus 39·1 per cent), compared with rates in patients not receiving each therapy. CONCLUSION: Appropriate risk factor modification could significantly reduce long-term mortality in patients with AAA. In the UK, up to 30 per cent of patients are not currently receiving these medications.


Asunto(s)
Aneurisma de la Aorta Abdominal/mortalidad , Anciano , Anciano de 80 o más Años , Antihipertensivos/uso terapéutico , Aneurisma de la Aorta Abdominal/complicaciones , Cardiotónicos/uso terapéutico , Enfermedades Cardiovasculares/complicaciones , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/prevención & control , Causas de Muerte , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/uso terapéutico , Medición de Riesgo
8.
J Evol Biol ; 29(11): 2191-2204, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27470674

RESUMEN

For many vertebrate species, bite force plays an important functional role. Ecological characteristics of a species' niche, such as diet, are often associated with bite force. Previous evidence suggests a biomechanical trade-off between rodents specialized for gnawing, which feed mainly on seeds, and those specialized for chewing, which feed mainly on green vegetation. We tested the hypothesis that gnawers are stronger biters than chewers. We estimated bite force and measured skull and mandible shape and size in 63 genera of a major rodent radiation (the myomorph sigmodontines). Analysis of the influence of diet on bite force and morphology was made in a comparative framework. We then used phylogenetic path analysis to uncover the most probable causal relationships linking diet and bite force. Both granivores (gnawers) and herbivores (chewers) have a similar high bite force, leading us to reject the initial hypothesis. Path analysis reveals that bite force is more likely influenced by diet than the reverse causality. The absence of a trade-off between herbivores and granivores may be associated with the generalist nature of the myomorph condition seen in sigmodontine rodents. Both gnawing and chewing sigmodontines exhibit similar, intermediate phenotypes, at least compared to extreme gnawers (squirrels) and chewers (chinchillas). Only insectivorous rodents appear to be moving towards a different direction in the shape space, through some notable changes in morphology. In terms of diet, natural selection alters bite force through changes in size and shape, indicating that organisms adjust their bite force in tandem with changes in food items.


Asunto(s)
Evolución Biológica , Fuerza de la Mordida , Dieta , Roedores/anatomía & histología , Animales , Fenómenos Biomecánicos , Filogenia , Cráneo
9.
Eur J Vasc Endovasc Surg ; 51(5): 674-81, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26947541

RESUMEN

OBJECTIVE/BACKGROUND: The growth rates of thoracic aortic aneurysms (TAAs) and factors influencing their expansion are poorly understood. This study aimed to review systematically published literature describing TAA expansion and examine factors that may be associated with this. METHODS: A comprehensive search of MEDLINE and Embase databases was performed until 30 April 2015. Studies describing rates of TAA growth were identified and systematically reviewed. Outcomes of interest were TAA growth rates and associated factors. Study quality was assessed using Scottish Intercollegiate Guidelines Network quality checklists for cohort studies. RESULTS: Eleven publications, involving 1383 patients, met the eligibility criteria and were included in the review. Included studies were generally low in quality. Aneurysm measurement and growth-rate estimation techniques were inconsistently reported. Mean growth rates for all TAAs ranged from 0.2 to 4.2 mm/year. Mean growth rates for ascending and aortic arch aneurysms ranged from 0.2 to 2.8 mm/year, while those for descending and thoracoabdominal aneurysms ranged from 1.9 to 3.4 mm/year in studies reporting according to anatomical location. Large aneurysm size, distal aneurysm locations, presence of Marfan's syndrome, and bicuspid aortic valve were consistently associated with accelerated TAA growth. Presence of chronic dissection and chronic obstructive pulmonary disorder were also implicated as risk factors for faster TAA growth. Associations between medical comorbidity and aneurysm expansion were conflicting. Previous aortic surgery and anticoagulants were reported to have a protective effect on aneurysm growth in two studies. CONCLUSION: There is a shortfall in the understanding of TAA expansion rates. Existing studies are heterogeneous in methodology and reported outcomes. Identified unifying themes suggest that TAAs grow at a slow rate with large presenting diameter, distal aneurysm, and history of bicuspid aortic valve or Marfan's syndrome serving as main risk factors for accelerated aneurysm growth. High-quality studies with a standardised approach to TAA growth assessment are required.


Asunto(s)
Aneurisma de la Aorta Torácica/etiología , Aneurisma de la Aorta Torácica/patología , Progresión de la Enfermedad , Humanos , Factores de Riesgo
10.
Eur J Vasc Endovasc Surg ; 52(4): 458-465, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27527570

RESUMEN

BACKGROUND: The chimney technique using parallel grafts offers an alternative to fenestrated or branched endovascular solutions for juxtarenal and suprarenal aneurysms. Endograft deployment proximal to the renal or visceral ostia is combined with parallel stents to the aortic side branches. Application of the chimney technique using the Nellix device (Ch-EVAS) may offer some potential advantages with respect to the seal between the endograft and the parallel grafts. This study aimed to investigate the feasibility and efficacy of the Nellix endovascular aneurysm sealing (EVAS) system in conjunction with parallel grafts for the treatment of juxtarenal and suprarenal aneurysms. METHODS: A prospective evaluation of patients treated for juxtarenal and suprarenal non-ruptured aortic aneurysms using Ch-EVAS was undertaken in a single vascular unit. Patients were treated with this technique if they were unsuitable for either open repair or a custom-made complex branched/fenestrated endograft. Procedural, postoperative morbidity, and mortality data were recorded. RESULTS: Between March 2013 and April 2015, 28 patients were treated with Ch-EVAS. The median age was 75 years (range 60-87 years) and the median aneurysm diameter 66 mm (IQR 60-73 mm). Eight patients underwent suprarenal aneurysm repair including parallel grafts in the superior mesenteric artery and renal arteries. Five patients had a double chimney configuration; all the other patients were treated with a single chimney configuration. There was one 30-day or in-hospital mortality in a patient with a symptomatic aneurysm (4%) and three further deaths within 1 year of follow-up. One proximal type I endoleak and one type II endoleak occurred. Four patients underwent a reintervention. One patient experienced a transient ischemic attack and two patients suffered from a minor stroke (7%), therefore the total number of cerebrovascular complications was 11%. No patient required postoperative renal replacement therapy. CONCLUSIONS: Ch-EVAS appears to offer a feasible solution for juxtarenal and suprarenal aneurysms with adverse morphology. In this short-term follow-up endoleak rates were low and re-intervention rates were acceptable. Outcomes over extended follow-up will determine the application of this novel technique and better define which patients and aneurysm morphology can be treated effectively.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular/instrumentación , Procedimientos Endovasculares/instrumentación , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad
11.
Phys Rev Lett ; 114(23): 233602, 2015 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-26196802

RESUMEN

We measure the quantum speed of the state evolution of the field in a weakly driven optical cavity QED system. To this end, the mode of the electromagnetic field is considered as a quantum system of interest with a preferential coupling to a tunable environment: the atoms. By controlling the environment, i.e., changing the number of atoms coupled to the optical cavity mode, an environment-assisted speed-up is realized: the quantum speed of the state repopulation in the optical cavity increases with the coupling strength between the optical cavity mode and this non-Markovian environment (the number of atoms).

12.
Eur J Vasc Endovasc Surg ; 49(5): 606-9, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25817562

RESUMEN

OBJECTIVES: To identify evidence to guide the vascular surgeon as to the relevance of renal artery stenting in a patient with symptomatic renal artery stenosis undergoing elective endovascular aortic aneurysm repair (EVAR). METHODS: A comprehensive literature search of MEDLINE was performed without time limits. The following terms were used in the first instance: renal artery stenting and renal artery stenosis, and any other analogous terms identified during the search. Selection criteria were set to randomised control trials. RESULTS: Despite several large, randomised controlled trials investigating renal artery stenting against medical treatment alone in symptomatic renal artery stenosis, there has been no significant benefit identified in terms of improvement in renal function, control of blood pressure, or need for dialysis. The stented populations were also more likely to suffer from complications caused by the procedure such as bleeding, cholesterol embolisation and flash pulmonary oedema. CONCLUSION: There is no evidence for the use of renal artery stenting over optimal medical management in the treatment of patients with symptomatic atherosclerotic renal artery stenosis, irrelevant of the degree of stenosis. In the setting of EVAR, prevention of deterioration of renal function should be with involvement of the renal physicians, adequate hydration, and use of minimal contrast agent. Repair should be undertaken in centres with access to 24-hour haemofiltration services.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Riñón/irrigación sanguínea , Selección de Paciente , Obstrucción de la Arteria Renal/cirugía , Arteria Renal/cirugía , Stents , Anciano , Aneurisma de la Aorta Abdominal/diagnóstico , Humanos , Riñón/cirugía , Masculino , Obstrucción de la Arteria Renal/diagnóstico , Procedimientos Quirúrgicos Vasculares
13.
Eur J Vasc Endovasc Surg ; 50(3): 320-30, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26116489

RESUMEN

BACKGROUND: Improved critical care, pre-operative optimization, and the advent of endovascular surgery (EVAR) have improved 30 day mortality for elective abdominal aortic aneurysm (AAA) repair. It remains unknown whether this has translated into improvements in long-term survival, particularly because these factors have also encouraged the treatment of older patients with greater comorbidity. The aim of this study was to quantify how 5 year survival after elective AAA repair has changed over time. METHODS: A systematic review was performed identifying studies reporting 5 year survival after elective infrarenal AAA repair. An electronic search of the Embase and Medline databases was conducted to January 2014. Thirty-six studies, 60 study arms, and 107,814 patients were identified. Meta-analyses were conducted to determine 5 year survival and to report whether 5 year survival changed over time. RESULTS: Five-year survival was 69% (95% CI 67 to 71%, I(2) = 87%). Meta-regression on study midpoint showed no improvement in 5 year survival over the period 1969-2011 (log OR -0.001, 95% CI -0.014-0.012). Larger average aneurysm diameter was associated with poorer 5 year survival (adjusted log OR -0.058, 95% CI -0.095 to -0.021, I(2) = 85%). Older average patient age at surgery was associated with poorer 5 year survival (adjusted log OR -0.118, 95% CI -0.142 to -0.094, I(2) = 70%). After adjusting for average patient age, an improvement in 5 year survival over the period that these data spanned was obtained (adjusted log OR 0.027, 95% CI 0.012 to 0.042). CONCLUSION: Five-year survival remains poor after elective AAA repair despite advances in short-term outcomes and is associated with AAA diameter and patient age at the time of surgery. Age-adjusted survival appears to have improved; however, this cohort as a whole continues to have poor long-term survival. Research in this field should attempt to improve the life expectancy of patients with repaired AAA and to optimise patient selection.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Factores de Edad , Anciano , Aneurisma de la Aorta Abdominal/diagnóstico , Aneurisma de la Aorta Abdominal/mortalidad , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/mortalidad , Procedimientos Quirúrgicos Electivos , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Medición de Riesgo , Factores de Riesgo , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
14.
Eur J Vasc Endovasc Surg ; 50(2): 157-64, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25892319

RESUMEN

OBJECTIVE: Endovascular aneurysm sealing (EVAS) has been proposed as a novel alternative to endovascular aneurysm repair (EVAR) in patients with infrarenal abdominal aortic aneurysms (AAA). The early clinical experience, technical refinements, and learning curve of EVAS in the treatment of AAA at a single institution are presented. METHODS: One-hundred and five patients were treated with EVAS between March 2013 and November 2014. Prospective data were recorded on consecutive patients receiving EVAS. Data included demographics, preoperative aneurysm morphology, and 30-day outcomes, including rates of endoleak, limb occlusion, reintervention, and death. Postoperative imaging consisted of duplex ultrasound and computed tomographic angiography. RESULTS: The mean age of the cohort was 76 ± 8 years and 12% were female. Adverse neck morphology was present in 72 (69%) patients, including aneurysm neck length <10 mm (20%), neck diameter >32 mm (18%), ß-angulation >60° (21%), and conical aneurysm neck (51%). There was one death within 30 days. The incidence of Type 1 endoleak within 30 days was 4% (n = 4); all were treated successfully with transcatheter embolisation. All four proximal endoleaks were associated with technical issues that resulted in procedure refinement, and all were in patients with adverse proximal aortic necks. The persistent Type 1 endoleak rate at 30 days was 0% and there were no Type 2 or Type 3 endoleaks. Angioplasty and adjunctive stenting were performed for postoperative limb stenosis in three patients (3%). CONCLUSIONS: EVAS appears to be associated with reasonable 30-day outcomes despite the necessity of procedural evolution in the early adoption of this technique. EVAS appears to be applicable to patients with challenging aortic morphology and endoleak rates should reduce with procedural experience. The utility of EVAS will be defined by the durability of the device in long-term follow-up, although the absence of Type 2 endoleaks is encouraging.


Asunto(s)
Angioplastia de Balón , Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular , Anciano , Anciano de 80 o más Años , Angioplastia de Balón/efectos adversos , Angioplastia de Balón/instrumentación , Angioplastia de Balón/mortalidad , Aneurisma de la Aorta Abdominal/diagnóstico , Aneurisma de la Aorta Abdominal/mortalidad , Aortografía/métodos , Prótesis Vascular , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/instrumentación , Implantación de Prótesis Vascular/mortalidad , Embolización Terapéutica , Endofuga/diagnóstico , Endofuga/etiología , Endofuga/terapia , Femenino , Oclusión de Injerto Vascular/diagnóstico , Oclusión de Injerto Vascular/etiología , Oclusión de Injerto Vascular/terapia , Humanos , Londres , Masculino , Estudios Prospectivos , Diseño de Prótesis , Stents , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Ultrasonografía Doppler Dúplex
15.
J Hosp Infect ; 145: 59-64, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38141666

RESUMEN

BACKGROUND: Mandatory mask-wearing policies were one of several measures employed to reduce hospital-acquired SARS-CoV-2 infection throughout the pandemic. Many nations have removed healthcare mask mandates, but there remains a risk of new SARS-CoV-2 variants or epidemics of other respiratory viruses. AIM: To demonstrate the impact of removing the healthcare mask mandate. METHODS: SARS-CoV-2 infections were analysed in a large teaching hospital for 40 weeks in 2022 using a controlled interrupted time-series design. The intervention was the removal of a staff/visitor surgical mask-wearing policy for the most wards at week 26 (intervention group) with a subset of specific wards retaining the mask policy (control group). The hospital-acquired SARS-CoV-2 infection rate was adjusted by the underlying community infection rate. FINDINGS: In the context of a surge in SARS-CoV-2 infection, removal of the mask mandate for staff/visitors was not associated with a statistically significant change in the rate of nosocomial SARS-CoV-2 infection in the intervention group (incidence rate ratio: 1.105; 95% confidence interval: 0.523-2.334; P = 0.79) and there was no post-intervention trend (1.013; 0.932-1.100; P = 0.76) to suggest a delayed effect. The control group also showed no immediate or delayed change in infection rate. CONCLUSION: No evidence was found that removal of a staff/visitor mask-wearing policy had a significant effect on the rate of hospital-acquired SARS-CoV-2 infection. This does not demonstrate that masks were ineffective through the pandemic, but provides some objective evidence to justify the removal of healthcare mask mandates once there was widespread immunity and reduced disease severity.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , SARS-CoV-2 , Pandemias/prevención & control , Máscaras , Hospitales
16.
Ecol Lett ; 16(5): 635-41, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23461543

RESUMEN

Conservationists often advocate for landscape approaches to wildlife management while others argue for physical separation between protected species and human communities, but direct empirical comparisons of these alternatives are scarce. We relate African lion population densities and population trends to contrasting management practices across 42 sites in 11 countries. Lion populations in fenced reserves are significantly closer to their estimated carrying capacities than unfenced populations. Whereas fenced reserves can maintain lions at 80% of their potential densities on annual management budgets of $500 km(-2) , unfenced populations require budgets in excess of $2000 km(-2) to attain half their potential densities. Lions in fenced reserves are primarily limited by density dependence, but lions in unfenced reserves are highly sensitive to human population densities in surrounding communities, and unfenced populations are frequently subjected to density-independent factors. Nearly half the unfenced lion populations may decline to near extinction over the next 20-40 years.


Asunto(s)
Carnívoros , Conservación de los Recursos Naturales/métodos , Leones , Densidad de Población , Animales , Conservación de los Recursos Naturales/economía , Ghana , Humanos , Namibia , Dinámica Poblacional , Sector Privado , Sudáfrica
17.
Br J Surg ; 100(10): 1302-11, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23797788

RESUMEN

BACKGROUND: Lifelong surveillance is standard after endovascular repair of abdominal aortic aneurysm (EVAR), but remains costly, heterogeneous and poorly calibrated. This study aimed to develop and validate a scoring system for aortic complications after EVAR, informing rationalized surveillance. METHODS: Patients undergoing EVAR at two centres were studied from 2004 to 2010. Preoperative morphology was quantified using three-dimensional computed tomography according to a validated protocol, by investigators blinded to outcomes. Proportional hazards modelling was used to identify factors predicting aortic complications at the first centre, and thereby derive a risk score. Sidak tests between risk quartiles dichotomized patients to low- or high-risk groups. Aortic complications were reported by Kaplan-Meier analysis and risk groups were compared by log rank test. External validation was by comparison of aortic complications between risk groups at the second centre. RESULTS: Some 761 patients, with a median age of 75 (interquartile range 70-80) years, underwent EVAR. Median follow-up was 36 (range 11-94) months. Physiological variables were not associated with aortic complications. A morphological risk score incorporating maximum aneurysm diameter (P < 0·001) and largest common iliac diameter (measured 10 mm from the internal iliac origin; P = 0·004) allocated 75 per cent of patients to a low-risk group, with excellent discrimination between 5-year rates of aortic complication in low- and high-risk groups at both centres (centre 1: 12 versus 31 per cent, P < 0·001; centre 2: 12 versus 45 per cent, P = 0·002). CONCLUSION: The risk score uses commonly available morphological data to stratify the rate of complications after EVAR. The proposals for rationalized surveillance could provide clinical and economic benefits.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Procedimientos Endovasculares/métodos , Complicaciones Posoperatorias/prevención & control , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Abdominal/patología , Endofuga/etiología , Endofuga/patología , Humanos , Aneurisma Ilíaco/patología , Imagenología Tridimensional , Estimación de Kaplan-Meier , Cuidados a Largo Plazo/métodos , Estudios Prospectivos , Reoperación , Medición de Riesgo/métodos , Tomografía Computarizada por Rayos X , Anomalía Torsional/etiología , Anomalía Torsional/patología
18.
Eur J Vasc Endovasc Surg ; 46(5): 533-41, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24091096

RESUMEN

OBJECTIVE: To report the contemporary life expectancy of patients undergoing abdominal (AAA) or thoracic aortic aneurysm (TAA) repair in England, relative to a healthy control population. METHODS: A retrospective observational case-control study was carried out of Hospital Episode Statistics (HES) data, an administrative dataset covering the entire English National Health Service. Patients undergoing elective repair of an abdominal or thoracic aortic aneurysm in an English NHS hospital between April 2006 and March 2011 were included. Outcome measures were 5-year all-cause mortality (in- and out-of-hospital) and adverse cardiovascular events (myocardial infarction, stroke, emergency amputation or limb revascularisation). RESULTS: 19,505 AAA and 730 TAA repairs were identified, with 75,260 and 2,721 control participants, respectively, and 27.5 (1.0-60.0) months' median (range) follow-up. Five-year survival was 67.4% for AAA against 81.1% for control participants, and 65.3% for TAA against 89.1% for control participants (p < .001). Freedom from adverse cardiovascular events was 86.1% for AAA against 93% for control participants and 89.1% for TAA against 94.4% for control participants (p < .001). CONCLUSION: Long-term survival remains poor after aneurysm repair and adverse cardiovascular events are common relative to the wider population. Further research is required to characterise and optimise cardiovascular risk prevention in patients with aortic aneurysms.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Aneurisma de la Aorta Torácica/cirugía , Hospitales/estadística & datos numéricos , Sobrevivientes/estadística & datos numéricos , Anciano , Amputación Quirúrgica/estadística & datos numéricos , Aneurisma de la Aorta Abdominal/mortalidad , Aneurisma de la Aorta Torácica/mortalidad , Procedimientos Quirúrgicos Electivos , Inglaterra/epidemiología , Mortalidad Hospitalaria , Humanos , Estimación de Kaplan-Meier , Esperanza de Vida , Modelos Logísticos , Persona de Mediana Edad , Análisis Multivariante , Infarto del Miocardio/etiología , Infarto del Miocardio/mortalidad , Oportunidad Relativa , Modelos de Riesgos Proporcionales , Reoperación , Estudios Retrospectivos , Factores de Riesgo , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/mortalidad , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/efectos adversos , Procedimientos Quirúrgicos Vasculares/mortalidad
19.
Sci Rep ; 13(1): 20415, 2023 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-37990118

RESUMEN

Habitat selection studies facilitate assessing and predicting species distributions and habitat connectivity, but habitat selection can vary temporally and among individuals, which is often ignored. We used GPS telemetry data from 96 Gray wolves (Canis lupus) in the western Great Lakes region of the USA to assess differences in habitat selection while wolves exhibited resident (territorial) or non-resident (dispersing or floating) movements and discuss implications for habitat connectivity. We used a step-selection function (SSF) to assess habitat selection by wolves exhibiting resident or non-resident movements, and modeled circuit connectivity throughout the western Great Lakes region. Wolves selected for natural land cover and against areas with high road densities, with no differences in selection among wolves when resident, dispersing, or floating. Similar habitat selection between resident and non-resident wolves may be due to similarity in environmental conditions, when non-resident movements occur largely within established wolf range rather than near the periphery or beyond the species range. Alternatively, non-resident wolves may travel through occupied territories because higher food availability or lower human disturbance outweighs risks posed by conspecifics. Finally, an absence of differences in habitat selection between resident and non-resident wolf movements may be due to other unknown reasons. We recommend considering context-dependency when evaluating differences in movements and habitat use between resident and non-resident individuals. Our results also provide independent validation of a previous species distribution model and connectivity analysis suggesting most potential wolf habitat in the western Great Lakes region is occupied, with limited connectivity to unoccupied habitat.


Asunto(s)
Lobos , Humanos , Animales , Ecosistema , Territorialidad , Movimiento , Great Lakes Region
20.
Br J Surg ; 99(4): 494-505, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22190106

RESUMEN

BACKGROUND: Over the past 50 years the management of vascular trauma has changed from mandatory surgical exploration to selective non-operative treatment, where possible. Accurate, non-invasive, diagnostic imaging techniques are the key to this strategy. The purpose of this review was to define optimal first-line imaging in patients with suspected vascular injury in different anatomical regions. METHODS: A systematic review was performed of literature relating to radiological diagnosis of vascular trauma over the past decade (2000-2010). Studies were included if the main focus was initial diagnosis of blunt or penetrating vascular injury and more than ten patients were included. RESULTS: Of 1511 titles identified, 58 articles were incorporated in the systematic review. Most described the use of computed tomography angiography (CTA). The application of duplex ultrasonography, magnetic resonance imaging/angiography and transoesophageal echocardiography was described, but significant drawbacks were highlighted for each. CTA displayed acceptable sensitivity and specificity for diagnosing vascular trauma in blunt and penetrating vascular injury within the neck and extremity, as well as for blunt aortic injury. CONCLUSION: Based on the evidence available, CTA should be the first-line investigation for all patients with suspected vascular trauma and no indication for immediate operative intervention.


Asunto(s)
Lesiones del Sistema Vascular/diagnóstico , Heridas no Penetrantes/diagnóstico , Heridas Penetrantes/diagnóstico , Abdomen/irrigación sanguínea , Angiografía/métodos , Aorta/lesiones , Brazo/irrigación sanguínea , Humanos , Pierna/irrigación sanguínea , Angiografía por Resonancia Magnética , Cuello/irrigación sanguínea , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X , Ultrasonografía Doppler Dúplex
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