ABSTRACT
INTRODUÇÃO: A Insuficiência Cardíaca com Fração de Ejeção Preservada (ICFEP) é uma condição clínica caracterizada por intolerância ao esforço e, nesse contexto, ferramentas que possam mensurar objetivamente este sintoma podem ser de grande valor na prática clínica. A abordagem diagnóstica atual da ICFEP requer aplicação de escores. O escore europeu HFA-PEFF, considera domínios morfológico, funcional e de peptídeos natriuréticos. Cada domínio tem um critério maior, que vale 2 pontos, e um critério menor, que vale 1 ponto. Se o total do escore for ≥ 5 pontos, o paciente tem diagnóstico de ICFEP. O teste de caminhada de seis minutos (TC6min) é uma ferramenta capaz de avaliar objetivamente a capacidade funcional traduzindo a habilidade dos pacientes em realizar tarefas cotidianas. OBJETIVOS: Avaliar a capacidade funcional de uma população de indivíduos em investigação para ICFEP. MÉTODOS: Trata-se de um estudo observacional transversal realizado em uma população de indivíduos com suspeita de ICFEP de um centro terciário de cardiologia. Foram incluídos sujeitos que realizaram o TC6min e categorizados de acordo com a probabilidade de ICFEP pelo escore HFA-PEFF. A normalidade dos dados foi avaliada pelo teste Shapiro-Wilk e a comparação entre os grupos foi realizada por meio do teste de Kruskal-Wallis. O nível de confiança adotado foi de 95%. Realizou-se ainda modelos de regressão linear univariado e multivariado. RESULTADOS: A amostra foi 105 indivíduos com idade de 59,5 ± 12,0 anos, 64% sexo feminino, IMC=31(5,8) Kg/m². A probabilidade de ICFEP foi baixa em 32 indivíduos, intermediária em 46; e alta em 27. A distância percorrida no TC6min foi de 416(±90) m. Para indivíduos com baixa probabilidade a distância percorrida foi de 472(±72) m, probabilidade intermediária de 406(±73) m e com alta probabilidade 356(±96) m. A diferença na distância percorrida entres os grupos com alta e baixa probabilidade de ICFEP foi estatisticamente significativa (P<0,05). Em um modelo de regressão multivariada, o efeito se manteve quando ajustado para idade, sexo e IMC. CONCLUSÃO: O presente estudo sugere que indivíduos com alta probabilidade de ICFEP classificados pelo escore HFA-PEF percorreram distâncias menores no TC6min quando comparados a indivíduos sem ICFEP (baixa probabilidade). Estes achados demonstram o valor clínico do TC6min na avaliação de indivíduos com suspeita de ICFEP. Palavras chaves: Insuficiência Cardíaca com Fração de Ejeção Preservada, Teste de Caminhada de Seis Minutos, Capacidade Funcional.
Subject(s)
Heart Failure, Diastolic , Walk TestABSTRACT
Variation in squamate foot morphology is likely relevant during evolutionary processes of habitat colonization because distinct surfaces differ in energetic and functional demands for locomotion. We combined new foot morphological data with published information of limb and tail lengths to investigate evolutionary changes possibly associated with the differential usage of ecological settings by Tropidurinae species. Several traits exhibited significant phylogenetic signal, and we performed conventional and phylogenetic regressions of PC scores (retained from Principal Components Analyses of morphometric traits) on continuous ecological indices. Tropidurines from sandy habitats exhibit larger foot soles, opposite to the evolution of narrow feet in species that use branches and rocks. Also, species that usually move along trunks present longer femora. This study provides evidence for morphological adaptations associated with substrate usage in Tropidurinae, and suggests that opposite morphological profiles might evolve associated with the use of surfaces energetically and functionally contrasting, possibly leading to trade-offs.
Subject(s)
Adaptation, Physiological , Lizards/anatomy & histology , Phylogeny , Animals , Foot/anatomy & histology , Foot/physiology , Lizards/physiology , Locomotion , Male , Regression Analysis , Tail/anatomy & histology , Tail/physiologyABSTRACT
We investigated the evolution of anuran locomotor performance and its morphological correlates as a function of habitat use and lifestyles. We reanalysed a subset of the data reported by Zug (Smithson. Contrib. Zool. 1978; 276: 131) employing phylogenetically explicit statistical methods (n = 56 species), and assembled morphological data on the ratio between hind-limb length and snout-vent length (SVL) from the literature and museum specimens for a large subgroup of the species from the original paper (n = 43 species). Analyses using independent contrasts revealed that classifying anurans into terrestrial, semi-aquatic, and arboreal categories cannot distinguish between the effects of phylogeny and ecological diversification in anuran locomotor performance. However, a more refined classification subdividing terrestrial species into 'fossorials' and 'non-fossorials', and arboreal species into 'open canopy', 'low canopy' and 'high canopy', suggests that part of the variation in locomotor performance and in hind-limb morphology can be attributed to ecological diversification. In particular, fossorial species had significantly lower jumping performances and shorter hind limbs than other species after controlling for SVL, illustrating how the trade-off between burrowing efficiency and jumping performance has resulted in morphological specialization in this group.
Subject(s)
Adaptation, Biological/physiology , Anura/physiology , Biological Evolution , Ecosystem , Hindlimb/anatomy & histology , Locomotion/physiology , Animals , Anura/anatomy & histology , Hindlimb/physiology , Phylogeny , Regression Analysis , Species SpecificityABSTRACT
Different components of complex integrated systems may be specialized for different functions, and thus the selective pressures acting on the system as a whole may be conflicting and can ultimately constrain organismal performance and evolution. The vertebrate cranial system is one of the most striking examples of a complex system with several possible functions, being associated to activities as different as locomotion, prey capture, display and defensive behaviours. Therefore, selective pressures on the cranial system as a whole are possibly complex and may be conflicting. The present study focuses on the influence of potentially conflicting selective pressures (diet vs. locomotion) on the evolution of head shape in Tropidurinae lizards. For example, the expected adaptations leading to flat heads and bodies in species living on vertical structures may conflict with the need for improved bite performance associated with the inclusion of hard or tough prey into the diet, a common phenomenon in Tropidurinae lizards. Body size and six variables describing head shape were quantified in preserved specimens of 23 species, and information on diet and substrate usage was obtained from the literature. No phylogenetic signal was observed in the morphological data at any branch length tested, suggesting adaptive evolution of head shape in Tropidurinae. This pattern was confirmed by both factor analysis and independent contrast analysis, which suggested adaptive co-variation between the head shape and the inclusion of hard prey into the diet. In contrast to our expectations, habitat use did not constrain or drive head shape evolution in the group.
