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Pulmonary percutaneous valve implantation (PPVI) is feasible with satisfactory mid-term results in patients with native right ventricular outflow tract (RVOT) and has been increasingly used instead of surgically implantable pulmonary valves. Creating a stable landing zone with a diameter less than the largest commercially available valve (previously available 29 mm and currently available 32 mm) is crucial for technical success of the procedure, limiting the number of suitable candidates for PPVI. We report the case of PPVI with a 32 mm Myval transcatheter heart valve in a patient with a large native RVOT (pre-stented with AndraStent XXL mounted on a 35 × 60 mm valve balloon catheter) lesion who had Tetralogy of Fallot surgically corrected. The post-procedural outcomes of this case were satisfactory with no complications reported during the hospital stay.
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Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Insuficiência da Valva Pulmonar , Valva Pulmonar , Obstrução do Fluxo Ventricular Externo , Cateterismo Cardíaco , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Desenho de Prótese , Valva Pulmonar/diagnóstico por imagem , Valva Pulmonar/cirurgia , Insuficiência da Valva Pulmonar/diagnóstico por imagem , Insuficiência da Valva Pulmonar/etiologia , Insuficiência da Valva Pulmonar/cirurgia , Resultado do Tratamento , Obstrução do Fluxo Ventricular Externo/diagnóstico por imagem , Obstrução do Fluxo Ventricular Externo/etiologia , Obstrução do Fluxo Ventricular Externo/cirurgiaRESUMO
AIMS: Transcatheter implantation of pulmonary balloon-expandable stent-valves requires pre-stenting of the right ventricular outflow tract with large calibre stents. To increase awareness of the associated risks of this part of transcatheter pulmonary valve replacement therapy, we report potential fatal complications during the implantation of AndraStents® in the right ventricular outflow tract in six cases from five different European institutions and their management. METHOD AND RESULT: We present a retrospective case series analysis looking at the time period from 2013 to 2018. Of 127 AndraStents® implanted in the right ventricular outflow tract, in six patients, age from 13 to 71 years, a misconfiguration of the AndraStent® occurred forming a "diabolo"-configuration. During inflation of the balloon, the stent showed extreme "dog-boning", an expansion of the stent at both ends with the middle part remaining unexpanded. This led to rupture of the balloon and loss of manoeuvrability in four patients. Out of the total six cases, in four patients the stent was eventually expanded with high-pressure balloons, and in one case the stent was surgically retrieved. In one patient, in whom a percutaneous retrieval of the embolised stent was attempted, a fatal bleeding occurred. CONCLUSIONS: Pre-stenting of the right ventricular outflow tract by AndraStents® can lead to misconfiguration of the stent with potentially fatal complications. Rescue strategies of misconfigured stents include stent inflation and placement with high pressure non-compliant balloons or surgical backup. Interventional retrieval measures of AndraStents® cannot be advised.
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Angioplastia Coronária com Balão/efeitos adversos , Implante de Prótese de Valva Cardíaca/efeitos adversos , Falha de Prótese/etiologia , Valva Pulmonar , Stents/efeitos adversos , Obstrução do Fluxo Ventricular Externo/cirurgia , Adolescente , Adulto , Idoso , Angioplastia Coronária com Balão/instrumentação , Cateterismo Cardíaco/efeitos adversos , Feminino , Implante de Prótese de Valva Cardíaca/instrumentação , Humanos , Masculino , Estudos Retrospectivos , Adulto JovemRESUMO
Complex cases undergo step surgical and percutaneous procedures, including stent deployment. Concerns arise on stent removal at latest surgery. Our initial experience is presented. Forty-six stents in 35 patients were partially or totally removed at surgery. Univentricular heart was diagnosed in 20 patients. Stents were previously deployed in: ductus (6), right ventricle outflow tract (12), atrial septal defect (4), right pulmonary artery (4), left pulmonary artery (16), inferior vena cava (2), superior vena cava (1) and ascending aorta (1). Surgical procedures performed: 9 transplants, 6 Fontan, 4 Glenn, 1 comprehensive repair (Norwood + Glenn), 1 Glenn takedown, 8 conduit replacement, 2 Fallot, 2 Rastelli, 1 ventricular septal defect closure and 1 iatrogenic aortopulmonary window. Five ductal stents were clipped. Eleven stents in right ventricle, four ones in atrial septal defect, two in right pulmonary artery, seven in the left pulmonary artery and two in inferior vena cava were completely removed. Two stents in right pulmonary artery, one in superior vena cava, one in ascending aorta and nine in the left pulmonary artery were partially retrieved. Handling the stents in ductus, right ventricle and atrial septal defect was straightforward. On the contrary, stent removal in the ductus (comprehensive case), pulmonary branches, both vena cavae or aorta required short periods of deep hypothermia with circulatory arrest. Surgery over stents is increasing in complex, step procedures. Univentricular hearts are most prevalent. Congenital transplant surgery faces new challenges. Stent removal at the time of surgery may require deep hypothermic circulatory arrest.
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Procedimentos Cirúrgicos Cardíacos/métodos , Comunicação Interatrial/cirurgia , Ventrículos do Coração/anormalidades , Artéria Pulmonar/cirurgia , Stents , Aorta/cirurgia , Humanos , Pediatria , Estudos Prospectivos , Veia Cava Superior/cirurgiaRESUMO
Time series are proficiently converted into graphs via the horizontal visibility (HV) algorithm, which prompts interest in its capability for capturing the nature of different classes of series in a network context. We have recently shown [B. Luque et al., PLoS ONE 6, 9 (2011)] that dynamical systems can be studied from a novel perspective via the use of this method. Specifically, the period-doubling and band-splitting attractor cascades that characterize unimodal maps transform into families of graphs that turn out to be independent of map nonlinearity or other particulars. Here, we provide an in depth description of the HV treatment of the Feigenbaum scenario, together with analytical derivations that relate to the degree distributions, mean distances, clustering coefficients, etc., associated to the bifurcation cascades and their accumulation points. We describe how the resultant families of graphs can be framed into a renormalization group scheme in which fixed-point graphs reveal their scaling properties. These fixed points are then re-derived from an entropy optimization process defined for the graph sets, confirming a suggested connection between renormalization group and entropy optimization. Finally, we provide analytical and numerical results for the graph entropy and show that it emulates the Lyapunov exponent of the map independently of its sign.
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Algoritmos , Dinâmica não Linear , Oscilometria/métodos , Simulação por ComputadorRESUMO
In bears, reproduction is dependent on the body reserves accumulated during hyperphagia. The Cantabrian brown bear mainly feeds on nuts during the hyperphagia period. Understanding how landscape heterogeneity and vegetation productivity in human-dominated landscapes influence the feeding habits of bears may therefore be important for disentangling species-habitat relationships of conservation interest. We determined the spatial patterns of nut consumption by brown bears during the hyperphagia period in relation to landscape structure, characteristics of fruit-producing patches and vegetation productivity. For this purpose, we constructed foraging models based on nut consumption data (obtained by scat analysis), by combining vegetation productivity data, topographical variables and landscape metrics to identify nut foraging patterns during this critical period for bears. The average wooded area of patches where scats were collected and where the nuts that the bears had consumed were produced was larger than that of the corresponding patches where nuts were not produced. For scats collected outside of nut-producing patches, the distance between the scats and the patches was greatest for chestnut-producing patches. Elevation, Gross Primary Production (GPP) and the Aggregation Index (AI) were good predictors of acorn consumption in the models. Good model fits were not obtained for data on chestnut consumption in bears. The findings confirm that brown bears feeding on nuts show a preference for relatively large, highly aggregated patches with a high degree of diversity in the landscape pattern, which may help the bears to remain undetected. The nut prediction model highlights areas of particular importance for brown bears during hyperphagia. The human presence associated with sweet chestnut forest stands or orchards may make bears feel more vulnerable when feeding.
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Ursidae , Animais , Ecossistema , Frutas , Humanos , Hiperfagia , NozesRESUMO
In this work we present a simple and fast computational method, the visibility algorithm, that converts a time series into a graph. The constructed graph inherits several properties of the series in its structure. Thereby, periodic series convert into regular graphs, and random series do so into random graphs. Moreover, fractal series convert into scale-free networks, enhancing the fact that power law degree distributions are related to fractality, something highly discussed recently. Some remarkable examples and analytical tools are outlined to test the method's reliability. Many different measures, recently developed in the complex network theory, could by means of this new approach characterize time series from a new point of view.
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Background: Collaboration between cardiac surgeons and cardiologists can offer interventions that each specialist may not be able to offer on their own. This type of collaboration has been demonstrated with the hybrid Stage I in patients with hypoplastic heart syndrome. Since that time, a hybrid approach to cardiac interventions has been expanded to an incredible variety of potential indications. Methods: Seventy-one patients were scheduled for a hybrid procedure along 8 years. This was defined as close collaboration between surgeon and cardiologist working together in the same room, either cath-lab (27 patients) or theater (44 patients). Results: Six groups were arbitrarily defined. A: vascular cut-down in the cath-lab (27 neonates); B: bilateral banding (plus ductal stent) in hypoplastic left heart syndrome or alike (15 children); C: perventricular closure of muscular ventricular septal defect (10 cases); D: balloon/stenting of pulmonary branches along with major surgical procedure (12 kids); E: surgical implantation of Melody valve (six patients) and others (F, one case). Two complications were recorded: left ventricular free wall puncture and previous conduit tearing. Both drawbacks were successfully sort out under cardiopulmonary by-pass. Conclusion: Surgeon and cardiologist partnership can succeed where their isolated endeavors are not enough. Hybrid procedures keep on spreading, overcoming initial expectations. As a bridge to biventricular repair or transplant, bilateral banding plus ductal stent sounds interesting. Novel indications can be classified into different groups. Hybrid procedures are not complication-free.
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In a genetic study on brown bears (Ursus arctos) in the Cantabrian Mountains, Gregório et al. (2020) interpreted the asymmetrical gene flow they found from the eastern subpopulation towards the western one as an exodus of bears forced to flee from the eastern nucleus "with higher human disturbance and poaching", concluding that connectivity may be operating as a means for eastern Cantabrian bears to find more suitable territories. In this reply, we maintain that the explanations of Gregorio et al. contradict the source-sink theory and we also present demographic data not considered by these authors showing that the eastern subpopulation is not declining, but persistently increasing. After reviewing the demographic and genetic studies published during the last 20 years, we conclude that the connectivity between the two subpopulations is operating as a route which allows the regular movement of males and the restoration of the gene flow across the whole Cantabrian population.
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Fluxo Gênico , Ursidae/fisiologia , Animais , Feminino , Genética Populacional , Atividades Humanas , Humanos , Masculino , Dinâmica Populacional , EspanhaRESUMO
The origin and shape of metabolic scaling has been controversial since Kleiber found that basal metabolic rate of animals seemed to vary as a power law of their body mass with exponent 3/4, instead of 2/3, as a surface-to-volume argument predicts. The universality of exponent 3/4 -claimed in terms of the fractal properties of the nutrient network- has recently been challenged according to empirical evidence that observed a wealth of robust exponents deviating from 3/4. Here we present a conceptually simple thermodynamic framework, where the dependence of metabolic rate with body mass emerges from a trade-off between the energy dissipated as heat and the energy efficiently used by the organism to maintain its metabolism. This balance tunes the shape of an additive model from which different effective scalings can be recovered as particular cases, thereby reconciling previously inconsistent empirical evidence in mammals, birds, insects and even plants under a unified framework. This model is biologically motivated, fits remarkably well the data, and also explains additional features such as the relation between energy lost as heat and mass, the role and influence of different climatic environments or the difference found between endotherms and ectotherms.
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Metabolismo Basal , Termodinâmica , Animais , Fenômenos Bioquímicos , Tamanho Corporal , Modelos BiológicosRESUMO
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
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UNLABELLED: As the number of detected extrasolar planets increases, exoplanet databases become a valuable resource, confirming some details about planetary formation but also challenging our theories with new, unexpected properties. KEY WORDS: Exoplanets-Gravity-Planetary habitability and biosignatures. Astrobiology 16, 325-327.
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Exobiologia , Meio Ambiente Extraterreno , Filmes Cinematográficos , Planetas , Caminhada , GravitaçãoRESUMO
Abstract Introduction: Multipurpose solutions (MPS) for soft contact lenses (SCL) play an essential role in inhibiting potentially pathogenic agents. Their antimicrobial effectiveness is assessed in vitro and their safety in vivo, with clinical trials that include a combination of different solutions and lens materials. The objective is to assess the biocompatibility of a new SCL MPS produced in Colombia that contains polyhexamethylene biguanide (PHMB) and to determine its antimicrobial activity. Materials and Methods: This was a crossover study with 25 subjects who did not wear lens and who were fitted with different combinations of five SCL materials with either MPS or control physiological saline solution (CS). Corneal thickness, conjunctival hyperemia, corneal staining, and comfort were assessed after two hours of wearing SCL. Antimicrobial effectiveness was measured using ISO 14729 standard assays. Results: When considering SCL material, there was a statistically significant difference between the new MPS and the CS for Comfilcon A (p < 0.05). There was no statistical or clinically significant difference for corneal thickness or corneal staining between the combination of lens material and new MPS with the CS (p > 0.05). After two hours of lens insertion, comfort scores were higher than 7.8. The MPS reduced bacteria colony forming units (CFU) in over 3 log, and fungal CFU in over 1.0 log. Conclusions: The new MPS met the antimicrobial standards of ISO 14729, is considered safe and biocompatible with the ocular surface and retains high comfort levels.
Resumen Introducción: las soluciones multipropósito (SMP) para lentes de contacto blandos (LCB) desempeñan un papel esencial en la inhibición de agentes potencialmente patógenos. Su efectividad antimicrobiana se evalúa in vitro, y su seguridad, in vivo, con ensayos clínicos que incluyen una combinación de diferentes soluciones y materiales para lentes. El objetivo es evaluar la biocompatibilidad de una nueva SMP producida en Colombia que contiene polihexametileno biguanida (PHMB) y determinar su actividad antimicrobiana. Materiales y métodos: estudio cruzado con 25 sujetos no usuarios de lentes, que fueron adaptados con cinco combinaciones diferentes de materiales de LCB con una nueva SMP o solución salina fisiológica de control (CS). El grosor corneal, la hiperemia conjuntival, la tinción corneal y la comodidad se evaluaron después de dos horas de uso del LC. La efectividad antimicrobiana se midió utilizando ensayos estándar ISO 14729. Resultados: considerando el material del LCB, solo hubo una diferencia estadísticamente significativa entre la nueva SMP y el CS para el Comfilcon A (p < 0.05). Tampoco hubo diferencias estadísticamente o clínicamente significativas para el grosor corneal o la tinción corneal, entre la combinación del material del lente y la nueva SMP con el CS (p > 0.05). Después de dos horas de uso del lente, las puntuaciones de confort fueron superiores a 7.8. La SMP redujo las unidades formadoras de colonias (UFC) de bacterias en más de 3 log, y las UFC fúngicas en más de 1.0 log. Conclusiones: la nueva SMP cumplió con los estándares antimicrobianos de ISO 14729, y se considera segura y biocompatible con la superficie ocular, con altos niveles de confort.
Resumo Introdução: as soluções multipropósito (SMP) para lentes de contato macias (LCM) apresentam um papel essencial na inibição de agentes potencialmente patógenos. Sua eficácia como agente antimicrobiano se valia in vitro, e sua segurança, in vivo, como ensaios clínicos que incluem uma combinação de diferentes soluções e materiais para lentes. O objetivo é avaliar a biocompatibilidade de uma nova SMP produzida na Colômbia a base de polihexametileno biguanida (PHMB) e determinar seu potencial antimicrobiano. Materiais e métodos: estudo cruzado com 25 indivíduos não usuários de lentes, que foram adaptados com cinco combinações diferentes de LCM como uma nova SMP ou solução salina fisiológica como controle (CS). A espessura da córnea, a hiperemia conjuntival, a coloração da córnea e a comodidade, foram avaliadas após duas horas de uso da LCB. A eficácia antimicrobiana foi medida com ensaios padrão ISO 14729. Resultados: considerando o material da LCB, houve apenas uma diferença estatisticamente significativa entre a nova SMP e o CS, paro o Comfilcon A (p <0.05). Não houve diferença estatisticamente ou clinicamente significativa para a espessura da córnea ou a coloração da córnea, entre a combinação do material da lente e a nova SMP com o controle CS (p > 0.05). Após duas horas de uso, as pontuações de conforto foram superiores a 7,8. A SMP reduziu as unidades formadoras de colônias (UFC) de bactérias em mais de 3 log, e as UFC fúngicas em mais de 1.0 log. Conclusões: a nova SMP cumpriu com os padrões antimicrobianos ISO 14729, é considerada segura e biocompatível com a superfície ocular, com altos níveis de conforto.
Assuntos
Humanos , Lentes de Contato Hidrofílicas , Hiperemia , Células-TroncoRESUMO
The brown bear Ursus arctos L., 1758 population of the Cantabrian Mountains (northwestern Spain) became isolated from other bear populations in Europe about 500 years ago and has declined due to hunting and habitat degradation. At the beginning of the 20th century, the Cantabrian population split into eastern and western subpopulations, and genetic exchange between them ceased. In the early 1990s, total population size was estimated to be < 100 bears. Subsequently, reduction in human-caused mortality has brought about an increase in numbers, mainly in the western subpopulation, likely promoting male-mediated migration and gene flow from the western nucleus to the eastern. To evaluate the possible genetic recovery of the small and genetically depauperate eastern subpopulation, in 2013 and 2014 we genotyped hair and faeces samples (116 from the eastern subpopulation and 36 from the western) for 18 microsatellite markers. Data from the annual count of females with cubs of the year (COY) during the past twenty-six years was used to analyze demographic changes. The number of females with COY fell to a minimum of seven in the western and three in eastern subpopulations in the biennium 1993-1994 and reached a respective maximum of 54 and 10 individuals in 2013-2014. We also observed increased bear dispersal and gene flow, mainly from the western to the eastern subpopulation. Of the 26 unique genotypes detected in the eastern subpopulation, 14 (54%) presented an admixture composition, and seven (27%) were determined to be migrants from the western subpopulation. Hence, the two separated and clearly structured subpopulations identified in the past currently show some degree of genetic admixture. This research shows the partial demographic recovery and a change in genetic composition due to migration process in a population of bears that has been isolated for several centuries.
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In this paper we study in detail the behavior of random-walk networks (RWN's). These networks are a generalization of the well-known random Boolean networks (RBN's), a classical approach to the study of the genome. RWN's are also discrete networks, but their response is defined by small variations in the state of each gene, thus being a more realistic representation of the genome and a natural bridge between discrete and continuous models. RWN's show a clear transition between order and disorder. Here we explicitly deduce the formula of the critical line for the annealed model and compute numerically the transition points for quenched and annealed models. We show that RBN's and the annealed model of RWN's act as an upper and a lower limit for the quenched model of RWN's. Finally we calculate the limit of the annealed model for the continuous case.
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Implante de Prótese de Valva Cardíaca/efeitos adversos , Insuficiência da Valva Pulmonar/diagnóstico por imagem , Insuficiência da Valva Pulmonar/cirurgia , Valva Pulmonar/diagnóstico por imagem , Valva Pulmonar/cirurgia , Tetralogia de Fallot/diagnóstico por imagem , Tetralogia de Fallot/cirurgia , Obstrução do Fluxo Ventricular Externo/diagnóstico por imagem , Obstrução do Fluxo Ventricular Externo/etiologia , Obstrução do Fluxo Ventricular Externo/cirurgia , Humanos , Resultado do TratamentoRESUMO
The recently formulated theory of horizontal visibility graphs transforms time series into graphs and allows the possibility of studying dynamical systems through the characterization of their associated networks. This method leads to a natural graph-theoretical description of nonlinear systems with qualities in the spirit of symbolic dynamics. We support our claim via the case study of the period-doubling and band-splitting attractor cascades that characterize unimodal maps. We provide a universal analytical description of this classic scenario in terms of the horizontal visibility graphs associated with the dynamics within the attractors, that we call Feigenbaum graphs, independent of map nonlinearity or other particulars. We derive exact results for their degree distribution and related quantities, recast them in the context of the renormalization group and find that its fixed points coincide with those of network entropy optimization. Furthermore, we show that the network entropy mimics the Lyapunov exponent of the map independently of its sign, hinting at a Pesin-like relation equally valid out of chaos.
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Algoritmos , Dinâmica não LinearRESUMO
In April 2000, we collected and analyzed for parasites 174 feces belonging to 48 different and identified Cantabrian capercaillies (Tetrao urogallus cantabricus) from 39 lek sites in the Cantabrian Mountains (North Spain) and determined the factors related with prevalence and abundance of propagule excretion: (1) interrelations with other parasite species, (2) characteristics of the capercaillie population (number of capercaillies in the lek site, number of occupied lek sites in a 2-km area, and abundance trend), and (3) characteristics of the lek site (orientation and altitude). The higher prevalence was observed for Eimeria sp. oocysts (29% of feces). Capillaria-like eggs were the most frequently detected among nematodes (9%). Excretion of Heterakis sp., Ascaridia sp., and Trichostrongylus sp. eggs was low. The presence of Capillaria propagules in feces was negatively related with those of Eimeria and Heterakis. This could be explained by differences in parasite transmission and capercaillie exposure because Eimeria and Heterakis have direct life cycle, whereas subfamily Capillariinae includes many heteroxenous species. Capillaria eggs were more prevalent in lek sites at lower altitude, which could be explained by altitude-related factors such as humidity, temperature, or soil characteristics that may affect intermediate host abundance. Although no relation was found with host abundance, the low parasite species diversity, prevalence, and abundance may indirectly reflect the decline of the Cantabrian capercaillie populations.