Associations between Sarcopenia and trajectories of activities of daily living disability: a nationwide longitudinal study of middle-aged and older adults in China from 2011 to 2018.

BACKGROUND: Sarcopenia is an age-related clinical syndrome, which is associated with numerous adverse outcomes among older adults. The relationship between sarcopenia and activities of daily living (ADL) disability has been studied in China, but these findings usually focused on a single time point. The patterns of ADL can change over time and vary among individuals. Therefore, it is necessary to explore the association between sarcopenia and trajectories of ADL disability. METHODS: According to Asian Working Group for Sarcopenia (AWGS) 2019 criteria, muscle mass, muscle strength, and physical performance measurements were measured to diagnose sarcopenia. A six-item ADL score was used to measure ADL disability, and trajectories of ADL disability were identified by the latent class trajectory modelling (LCTM). Multiple logistic regression models were performed to examine the association between sarcopenia and trajectories of ADL disability. RESULTS: Among 9113 middle-aged and older adults, three trajectories of ADL disability were determined according to changes in ADL score during follow-up, including a mild-high trajectory (n = 648, 7.11%), followed by the low-mild trajectory (n = 3120, 34.24%) and low-low trajectory (n = 5345, 58.65%). After adjustment for covariates, severe sarcopenia was significantly associated with higher risks of being in the mild-high trajectory group (OR = 3.31, 95%CI: 2.10-5.22) and the low-mild trajectory group (OR = 1.44, 95%CI: 1.05-1.98), compared with the low-low trajectory group. This association was still observed when stratified by age and gender. In addition, participants with sarcopenic obesity were associated with a higher risk of ADL disability (OR = 3.99; 95% CI: 2.50-6.09). CONCLUSIONS: Among the middle-aged and older Chinese adults, sarcopenia and sarcopenic obesity were both associated with persistent higher trajectories of ADL disability. It suggested that early interventions to sarcopenia and sarcopenic obesity among the middle-aged and older adults may reduce the progression of ADL disability.

Morphological diversity and altitudinal differentiation of Aethopyga species.

The morphological characteristics of birds are an important tool for studying their adaptation and evolution. The morphological evolution of a clade is not only constrained by the phylogenetic relationship, but also influenced by ecological factors and interspecific competition. Aethopyga is a group of small nectar-eating birds with obvious sexual dimorphism. They have slender and decurved beaks, which reflect their unique diet and foraging mode. Traditional and geometric morphometrics were combined to characterize the body morphology and beak shape of six species of Aethopyga distributed in China. We aim to assess the roles of phylogeny, altitude, and species interactions to morphological evolution. The main distinguishing characteristic among these six species were overall body size, the ratio of body weight, culmen and tarsal length to body length, tail length and wing length, and beak shape (slender/straight vs. thick/decurved). Although these dimensions cannot distinguish all species, they can show a clear distribution trend, and there is a significant Mahalanobis distance between each pair of species. There were no significant phylogenetic signals in morphological traits. The results of PGLS analysis show that altitude is significantly correlated with log-transformed tarsus length and beak-shaped PC1 (slender/straight vs thick/decurved dimensions) across the six species analyzed. Mantel test shows that the distance matrix of beak morphological characteristics showed a significant correlation with the altitudinal distance matrix. The results indicated no significant phylogenetic signal in the morphological characteristics of six species. In terms of beak shape, species with greater overlap in elevation distribution have more similar morphological characteristics, that is, less morphological differentiation.

Complete mitochondrial genome of fire-tailed myzornis (Myzornis pyrrhoura) and white-browed fulvetta (Fulvetta vinipectus).

In this study, the complete mitochondrial genomes of Myzornis pyrrhoura and Fulvetta vinipectus were sequenced and described for the first time. The whole mitochondrial genomes of M. pyrrhoura and F. vinipectus are 17,397 bp and 16,961 bp in length, with the G + C percentage 46.34% and 47.36%, respectively. Both genomes contain 13 protein-coding genes, 22 transfer RNA genes, 2 ribosome RNA genes, and 1 non-coding control region. The arrangement of genes is identical to mitochondrial genomes of Sylviidae species reported previously. A phylogenetic reconstruction supported that M. pyrrhoura and F. vinipectus are members of family Sylviidae. The mitochondrial genomes of these two species reported here would be helpful in better understanding the phylogeny and evolution of Sylviidae.

Near-complete phylogeny and taxonomic revision of the world's babblers (Aves: Passeriformes).

The babblers are a diverse group of passerine birds comprising 452 species. The group was long regarded as a "scrap basket" in taxonomic classification schemes. Although several studies have assessed the phylogenetic relationships for subsets of babblers during the past two decades, a comprehensive phylogeny of this group has been lacking. In this study, we used five mitochondrial and seven nuclear loci to generate a dated phylogeny for babblers. This phylogeny includes 402 species (ca. 89% of the overall clade) from 75 genera (97%) and all five currently recognized families, providing a robust basis for taxonomic revision. Our phylogeny supports seven major clades and reveals several non-monophyletic genera. Divergence time estimates indicate that the seven major clades diverged around the same time (18-20 million years ago, Ma) in the early Miocene. We use the phylogeny in a consistent way to propose a new taxonomy, with seven families and 64 genera of babblers, and a new linear sequence of names.

Complete mitochondrial genome of yellow-rumped honeyguide Indicator xanthonotus (Piciformes: Indicatoridae).

In this study, we first sequenced and described the complete mitochondrial genome and phylogeny of Indicator xanthonotus. The whole genome of I. xanthonotus was 17,603 bp in length and contained 14 protein-coding genes, 22 transfer RNA genes, two ribosome RNA genes, and two non-coding control regions. The overall base composition of the mitochondrial DNA was 31.09% for A, 27.34% for T, 28.96% for C, and 12.61% for G, with a GC content of 41.57%. A phylogenetic tree strongly supported that I. xanthonotus clustered with another Piciformes species by high probability.

The complete mitochondrial genome and phylogenetic analysis of White-bellied Heron Ardea insignis (Pelecaniformes：Ardeidae).

The White-bellied Heron Ardea insignis is Critically Endangered wading bird. In this study, we first sequenced and described the complete mitochondrial genome and phylogeny of A. insignis. The whole genome of A. insignis was 18,656 bp in length and contained 14 protein-coding genes, 23 transfer RNA genes, two ribosome RNA genes, and two non-coding control regions. The overall base composition of the mitochondrial DNA was 30.86% for A, 24.60% for T, 30.48% for C, and 14.05% for G, with a GC content of 44.54%. A phylogenetic tree confirmed that A. insignis belonged to genus Ardea, family Ardeidae, and was sister to A. purpurea. This information will be useful in the current understanding of the phylogeny and evolution of Pelecaniformes.

Genomic differentiation and patterns of gene flow between two long-tailed tit species (Aegithalos).

Patterns of heterogeneous genomic differentiation have been well documented between closely related species, with some highly differentiated genomic regions ("genomic differentiation islands") spread throughout the genome. Differential levels of gene flow are proposed to account for this pattern, as genomic differentiation islands are suggested to be resistant to gene flow. Recent studies have also suggested that genomic differentiation islands could be explained by linked selection acting on genomic regions with low recombination rates. Here, we investigate genomic differentiation and gene-flow patterns for autosomes using RAD-seq data between two closely related species of long-tailed tits (Aegithalos bonvaloti and A. fuliginosus) in both allopatric and contact zone populations. The results confirm recent or ongoing gene flow between these two species. However, there is little evidence that the genomic regions that were found to be highly differentiated between the contact zone populations are resistant to gene flow, suggesting that differential levels of gene flow is not the cause of the heterogeneous genomic differentiation. Linked selection may be the cause of genomic differentiation islands between the allopatric populations with no or very limited gene flow, but this could not account for the heterogeneous genomic differentiation between the contact zone populations, which show evidence of recent or ongoing gene flow.

Evolution of beak morphology in the Ground Tit revealed by comparative transcriptomics.

BACKGROUND: Beak morphology exhibits considerable adaptive plasticity in birds, which results in highly varied or specialized forms in response to variations in ecology and life history. As the only parid species endemic to the Qinghai-Tibet Plateau, the Ground Tit (Parus humilis) has evolved a distinctly long and curved beak from other parids. An integration of morphometrics, phylogenetics, transcriptomics and embryology allows us to address the evolutionary and developmental mechanisms of the adaptive beak structure observed in the Ground Tit. RESULTS: A morphometric approach quantified that the Ground Tit has a comparatively longer and more decurved upper beaks than other parids. We estimated that the ancestor of the Ground Tit likely had a short straight upper beak similar to most current recognized parid species using an ancestral state reconstruction. This morphological specialization is considered an adaptation to its ground-oriented behavior on the high plateau. To identify genetic mechanisms behind this adaptive change, a comparative transcriptomic analysis was applied between the Ground Tit and its closely related species, the Great Tit (Parus major). We detected that 623 genes were significantly differentially expressed in embryonic upper beaks between the two species, 17 of which were functionally annotated to correlate with bone development and morphogenesis, although genes related to bone development were not found to undergo accelerated evolution in the Ground Tit. RT-qPCR validation confirmed differential expression of five out of eight genes that were selected from the 17 genes. Subsequent functional assays in chicken embryos demonstrated that two of these genes, FGF13 and ITGB3, may affect beak morphology by modulating levels of osteoblasts and osteoclasts. CONCLUSIONS: Our results provide preliminary evidence that development of the long decurved beak of the Ground Tit is likely regulated by transcriptional activities of multiple genes coordinating osteoblasts and osteoclasts. The integration of multiple approaches employed here sheds light on ecological and genetic mechanisms in the evolution of avian morphology.

Evolution of body morphology and beak shape revealed by a morphometric analysis of 14 Paridae species.

BACKGROUND: Morphological characters of birds reflect their adaptive evolution and ecological requirements and are also relevant to phylogenetic relationships within a group of related species. The tits (Paridae) are known to be outwardly homogeneous in shape, with one aberrant member, the Ground Tit (Pseudopodoces humilis), which is quite different from its relatives in both body morphology and beak shape. We combined traditional measurements and geometric morphometrics to quantify the variation in body morphology and beak shape of 14 Paridae species distributed in China. Based on these results, we sought to assess the contribution of phylogeny, altitude and species interactions to the evolution of morphological traits. RESULTS: The basic features for discriminating among the 14 species studied here were overall body size, the ratio of body and tail length to culmen and tarsus length, and beak shape (long/slender/pointy vs. short/robust/blunt). These dimensions clearly separate Ps. humilis and Melanochlora sultanea from the other species in shape space. Body length and PC3 of beak shape (round outline vs. straight outline) show significant phylogenetic signals. Across 14 species, altitude is related to tarsus, culmen length and PC1 of beak shape. Within Parus major, altitude is related to body weight, body length, culmen length and PC1 of body morphology. Morphological distances and geographic distances among species are positively correlated. CONCLUSIONS: The body morphology of Paridae species shows extensive evolutionary changes, while their beak has mainly evolved along the long/slender/pointy vs. short/robust/blunt dimension. Only body length and beak curvature show a phylogenetic signal. Altitude correlates with multiple traits both across and within species, suggesting that altitude is an important factor in promoting morphological divergence. The deviant appearance of Ps. humilis corresponds to its foraging and feeding adaptations to high-altitude steppe habitats. Our results also show a higher level of morphological divergence with greater difference in distribution ranges among the Paridae species involved in this study.