Using Body Composition Groups to Identify Children and Adolescents at Risk of Dyslipidemia

The impact of body composition on the early origin of chronic diseases is an increasingly appreciated phenomenon. Little is known about the characteristics of children with varying body composition. The aim of this study was to investigate serum lipid profiles and other characteristics in relation to body composition. The data of 1394 participants (aged 6 to <18 years) of the observational general population-based Austrian LEAD Study have been analyzed. Body composition groups were defined by appendicular lean mass (ALMI) and fat mass (FMI) indices assessed by DXA. Serum lipid profiles (triglycerides, LDL-c, HDL-c) and other characteristics (e.g., prematurity, smoke exposure, physical activity, nutrition) were investigated in these body composition groups. Different body composition groups, which are not distinguishable by BMI, exist. Children with high ALMI and high FMI showed higher triglycerides and LDL-c, but lower HDL-c levels. In contrast, levels did not differ between those with high FMI but low (or normal) ALMI, and other body composition groups. BMI should be interpreted cautiously, and body composition should be measured by more precise techniques. In particular, children and adolescents with high FMI who have concomitantly high ALMI should be followed closely in future studies to investigate whether they are at increased risk of cardiovascular problems.

Transcriptomics analysis reveals intracellular mutual regulation of coral-zooxanthella holobionts

Corals should make excellent models for cross-kingdom regulation research because of their natural animal-photobiont holobiont composition, yet a lack of studies and experimental data restricts their use. Here we integrate new full-length transcriptomes and small RNAs of four common reef-building corals with the published Symbiodinium C1 genome to gain deeper insight into mutual gene regulation in coral-zooxanthella holobionts. We show that zooxanthellae secrete miRNA to downregulate rejection from host coral cells, and that a potential correlation exists between miRNA diversity and physiological activity. Convergence of these holobionts' biological functions in different species is also revealed, which implies the low gene impact on bottom ecological niche organisms. This work provides evidence for the early origin of cross-kingdom regulation as a mechanism of self-defense autotrophs can use against heterotrophs, sheds more light on coral-zooxanthella holobionts, and contributes valuable data for further coral research.

The spread of the first introns in proto-eukaryotic paralogs

Spliceosomal introns are a unique feature of eukaryotic genes. Previous studies have established that many introns were present in the protein-coding genes of the last eukaryotic common ancestor (LECA). Intron positions shared between genes that duplicated before LECA could in principle provide insight into the emergence of the first introns. In this study we use ancestral intron position reconstructions in two large sets of duplicated families to systematically identify these ancient paralogous intron positions. We found that 20-35% of introns inferred to have been present in LECA were shared between paralogs. These shared introns, which likely preceded ancient duplications, were widespread across different functions, with the notable exception of nuclear transport. Since we observed a clear signal of pervasive intron loss prior to LECA, it is likely that substantially more introns were shared at the time of duplication than we can detect in LECA. The large extent of shared introns indicates an early origin of introns during eukaryogenesis and suggests an early origin of a nuclear structure, before most of the other complex eukaryotic features were established.

Early Appearance of Epicardial Adipose Tissue through Human Development

Background: Epicardial adipose tissue (EAT) is a visceral fat depot with unique anatomic, biomolecular and genetic features. Due to its proximity to the coronary arteries and myocardium, dysfunctional EAT may contribute to the development and progression of cardiovascular and metabolic-related adiposity-based chronic diseases. The aim of this work was to describe, by morphological techniques, the early origin of EAT. Methods: EAT adipogenesis was studied in 41 embryos from 32 gestational days (GD) to 8 gestational weeks (GW) and in 23 fetuses until full term (from 9 to 36 GW). Results: This process comprises five stages. Stage 1 appears as mesenchyme at 33–35 GD. Stage 2 is characterized by angiogenesis at 42–45 GD. Stage 3 covers up to 34 GW with the appearance of small fibers in the extracellular matrix. Stage 4 is visible around the coronary arteries, as multilocular adipocytes in primitive fat lobules, and Stage 5 is present with unilocular adipocytes in the definitive fat lobules. EAT precursor tissue appears as early as the end of the first gestational month in the atrioventricular grooves. Unilocular adipocytes appear at the eighth gestational month. Conclusions: Due to its early origin, plasticity and clinical implications, factors such as maternal health and nutrition might influence EAT early development in consequence.

Dynamic finite-element simulations reveal early origin of complex human birth pattern

Human infants are born neurologically immature, but whether this originates from conflicting selection pressures between bipedal locomotion and encephalization as suggested by the obstetrical dilemma remains controversial. Australopithecines are ideal for investigating this trade-off as they have a bipedally adapted pelvis, yet relatively small brains. Our finite-element birth simulations based on different pelvic reconstructions and a range of fetal head sizes indicate that australopithecines already possessed a human-like rotational birth pattern. Since only newborn head sizes smaller than those predicted for non-human primates leave adequate space for soft tissue between the bony pelvis and fetal skull, our data imply that australopithecines had secondarily altricial newborns and likely evolved cooperative breeding to care for their helpless infants. These prerequisites for advanced cognitive development therefore seem to have been corollary to skeletal adaptations to bipedal locomotion that preceded the appearance of the genus Homo and the increase in encephalization.

Early origin of sweet perception in the songbird radiation

Early events in the evolutionary history of a clade can shape the sensory systems of descendant lineages. Although the avian ancestor may not have had a sweet receptor, the widespread incidence of nectar-feeding birds suggests multiple acquisitions of sugar detection. In this study, we identify a single early sensory shift of the umami receptor (the T1R1-T1R3 heterodimer) that conferred sweet-sensing abilities in songbirds, a large evolutionary radiation containing nearly half of all living birds. We demonstrate sugar responses across species with diverse diets, uncover critical sites underlying carbohydrate detection, and identify the molecular basis of sensory convergence between songbirds and nectar-specialist hummingbirds. This early shift shaped the sensory biology of an entire radiation, emphasizing the role of contingency and providing an example of the genetic basis of convergence in avian evolution.

The evolution of feathers

&lt;p&gt;Feathers are a diagnostic character of birds, and yet new fossils show they likely originated more than 100 million years before the first birds. In fact, feathers probably occurred in all dinosaur groups, and in their cousins, the pterosaurs, as we showed in 2019. This finding confirms current knowledge of the genomic regulation of feather development. Our work stems from ten years of collaboration with Chinese colleagues, during which we set ourselves the task of understanding fossil feathers. Our first discovery was to answer the question, &amp;#8216;Will we ever know the colour of dinosaurs?&amp;#8217;. In 2010, we were able to announce the first objective evidence for colour in a dinosaur. Using ultrastructural studies of fossil feathers, we identified melanosomes for the first time in dinosaur feathers, and these demonstrated that Sinosauropteryx had ginger and white rings down its tail. Studies of other dinosaurs identified patterns of black, white, grey, brown, and ginger. This is part of a new wave in Palaeobiology where we apply objective approaches to provide testable hypotheses, once thought impossible in the historical sciences.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;Benton, M.J., Dhouailly, D., Jiang, B.Y., and McNamara, M. 2019. The early origin of feathers.&amp;#160;Trends in Ecology &amp; Evolution&amp;#160;34, 856-869 (doi: 10.1016/j.tree.2019.04.018).&lt;/p&gt;&lt;p&gt;https://dinocolour.blogs.bristol.ac.uk/&lt;/p&gt;&lt;p&gt;https://dinosaurs.blogs.bristol.ac.uk/&lt;/p&gt;

Mice Make Targeted Saccades

Humans read text, recognize faces, and process emotions using targeted saccadic eye movements. In the textbook model, this innate ability to make targeted saccades evolved in species with foveae or similar high-acuity retinal specializations that enable scrutiny of salient stimuli. According to the model, saccades made by species without retinal specializations (such as mice) are never targeted and serve only to reset the eyes after gaze-stabilizing movements. Here we show that mice innately make touch-evoked targeted saccades. Optogenetic manipulations revealed the neural circuit mechanisms underlying targeted saccades are conserved. Saccade probability is a U-shaped function of current eye position relative to the target, mirroring the simulated relationship between an object’s location within the visual field and the probability its next movement carries it out of view. Thus, a cardinal sophistication of our visual system may have had an unexpectedly early origin as an innate behavior that keeps stimuli in view.