Publications by authors named "Jean Keller"

"The whole day movement matters to health." has become an important topic while the associations between executive function and different movement behaviors (i.e.

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Horizontal gene transfers (HGT) have been observed across the tree of life. While their adaptive importance in bacteria is conspicuous, the occurrence of HGT and their evolutionary significance in Eukaryotes has only recently started to be considered. In this review, we explore the extent of HGT in the plant kingdom, indicating the widespread occurrence of microbe - plant HGT and Plant - Plant HGT.

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Using an explanatory sequential mixed-methods approach, this study investigated the development of fundamental motor skills (FMS) in 219 Head Start preschoolers (age = 4.33, = 0.63; 56% girls; 53% Hispanic) and examined how family environments, including parental and sibling influences, shapes FMS.

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Over the last decade, collaborative efforts in plant evolutionary research have elucidated the phylogenetic relationships in the green plant lineage and provided insights into the emergence of land plants from a group of terrestrial and freshwater streptophyte algae. A foremost finding was that the genetic underpinnings of several key traits emerged much earlier than land plants - they were present in their streptophyte algal progenitors. Currently, the field is at a crossroads, transitioning from genomics-informed descriptions of streptophyte algae to a functional understanding of molecular mechanisms underlying their unique physiology, as well as to understanding their origin and evolution.

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Arbuscular mycorrhiza (AM) with soilborne Glomeromycota fungi was pivotal in the conquest of land by plants almost half a billion years ago. In flowering plants, it is hypothesized that AM is initiated by the perception of AM fungi-derived chito- and lipochito-oligosaccharides (COs/LCOs) in the host via Lysin Motif Receptor-Like Kinases (LysM-RLKs). However, it remains uncertain whether plant perception of these molecules is a prerequisite for AM establishment and for its origin.

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Plant adaptation to terrestrial life started 450 million years ago and has played a major role in the evolution of life on Earth. The genetic mechanisms allowing this adaptation to a diversity of terrestrial constraints have been mostly studied by focusing on flowering plants. Here, we gathered a collection of 133 accessions of the model bryophyte Marchantia polymorpha and studied its intraspecific diversity using selection signature analyses, a genome-environment association study and a pangenome.

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Beetles that feed on the nutritionally depauperate and recalcitrant tissues provided by the leaves, stems, and roots of living plants comprise one-quarter of herbivorous insect species. Among the key adaptations for herbivory are plant cell wall-degrading enzymes (PCWDEs) that break down the fastidious polymers in the cell wall and grant access to the nutritious cell content. While largely absent from the non-herbivorous ancestors of beetles, such PCWDEs were occasionally acquired via horizontal gene transfer (HGT) or by the uptake of digestive symbionts.

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Plants have colonized lands 450 million years ago. This terrestrialization was facilitated by developmental and functional innovations. Recent evo-devo approaches have demonstrated that one of these innovations was the mutualistic arbuscular mycorrhizal symbiosis (AMS).

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Article Synopsis
  • Legumes form partnerships with AM fungi and rhizobia to enhance their nutrient intake, using specific structures in their roots for effective exchange.
  • The research focuses on Medicago truncatula, revealing that MtAnn1 protein plays a critical role in the formation of cytoplasmic cell bridges for rhizobia entry, influencing calcium signaling and infection success.
  • MtAnn1 not only contributes to rhizobia symbiosis but is also essential for arbuscule development in AM fungi, indicating its importance in ancient calcium-regulatory mechanisms for symbiotic infections.
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Many children in Head Start programs do not meet physical activity (PA) and dietary intake recommendations and have increased risk for obesity. The purpose of this pilot study was to formatively assess a multi-level intervention, exploring strategies to encourage PA and healthy eating among north Texas Head Start families. In year 1, 5 Head Start sites with 217 children began the Head Start to Healthy Lifestyles (HSHL) project.

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  • Disulfiram, although no longer approved for use in Germany over a decade ago, is still prescribed by many practitioners within the "Network for Alcohol Aversive Pharmacotherapy" (NAP), highlighting its ongoing relevance in treating alcoholism.
  • A survey conducted from 2019 to 2023 revealed that 1,579 treatment cases were reported, with 152 patients having drinking events, though most resulted in no serious complications.
  • The study found disulfiram to be generally well-tolerated, with common side effects including body odor and fatigue; importantly, many patients also had comorbid psychiatric conditions, and treatment often included additional therapies.
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  • This research explores how mutualistic symbiosis, specifically the relationship between fungi and green algae or cyanobacteria, has been crucial for the evolution of lichens.
  • The study involved sequencing the genomes of various lichen algal symbionts and non-symbiotic algae, revealing three independent instances where algae gained the ability to form lichen partnerships.
  • A specific enzyme (from the GH8 family) was identified as key to this symbiosis, having been acquired through horizontal gene transfer, which allowed these algae to better associate with fungal partners.
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  • Zygnematophyceae, a group of filamentous algae, are closely related to land plants, and this study sequenced four of their genomes, creating detailed chromosome-scale assemblies for three strains of Zygnema circumcarinatum.
  • The research identified key traits in their common ancestor with land plants that may have enabled plants to adapt to life on land, including expanded genes for signaling, environmental responses, and multicellular growth.
  • Additionally, the study revealed shared enzymes for cell wall synthesis between Zygnematophyceae and land plants, suggesting a genetic framework that integrates environmental responses with developmental growth over 600 million years of evolution.
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Non-specific lipid transfer proteins (nsLTPs) are antimicrobial peptides, involved in several plant biological processes including root nodule nitrogen fixation (RNF). Nodulating plants belonging to the RNF clade establish symbiosis with the nitrogen-fixing bacteria rhizobia (legumes symbiosis model) and Frankia (actinorhizal symbiosis model) leading to root nodule formation. nsLTPs are involved in processes active in early step of symbiosis and functional nodule in both models.

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  • The study aims to evaluate the effectiveness of COVID-19 booster doses in preventing hospitalizations and emergency department visits, providing insight for public health policies.
  • Data was collected from over 1.2 million adults at five health systems during the Omicron variant's rise, showing that approximately 37% received a booster dose.
  • The median number needed to vaccinate (NNV) to prevent one hospitalization was 205, with lower NNV for adults aged 65 and older and those with health conditions, indicating booster effectiveness varies by age and health status.
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Symbiotic interactions such as the nitrogen-fixing root nodule symbiosis (RNS) have structured ecosystems during the evolution of life. Here we aimed at reconstructing ancestral and intermediate steps that shaped RNS observed in extant flowering plants. We compared the symbiotic transcriptomic responses of nine host plants, including the mimosoid legume Mimosa pudica for which we assembled a chromosome-level genome.

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The filamentous and unicellular algae of the class Zygnematophyceae are the closest algal relatives of land plants. Inferring the properties of the last common ancestor shared by these algae and land plants allows us to identify decisive traits that enabled the conquest of land by plants. We sequenced four genomes of filamentous Zygnematophyceae (three strains of and one strain of ) and generated chromosome-scale assemblies for all strains of the emerging model system .

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In plants, the topological organization of membranes has mainly been attributed to the cell wall and the cytoskeleton. Additionally, few proteins, such as plant-specific remorins have been shown to function as protein and lipid organizers. Root nodule symbiosis requires continuous membrane re-arrangements, with bacteria being finally released from infection threads into membrane-confined symbiosomes.

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Rates of unintended pregnancy may be higher in women living with human immunodeficiency virus (WLWH) than in the general population, and it is unclear how populations of WLWH with intended and unintended pregnancy differ. We compared baseline characteristics and outcomes between WLWH with intended and unintended pregnancy. We conducted a retrospective analysis of WLWH enrolled in a human immunodeficiency virus (HIV) and Pregnancy clinic from 2003 to 2014.

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Limited empirical evidence is available about preschoolers' sedentary behavior (SB) and physical activity (PA) patterns in Head Start programs, we explored (a) preschoolers' SB and PA patterns (ranging from SB to light-moderate-vigorous physical activity [LMVPA]) and (b) their relationships with sociodemographic factors, weight status, and motor development. Participants included 216 preschoolers (  = 4.32 ± 0.

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The Zygnematophyceae is the sister clade to the land plants, but their biology remains mysterious. In a new study, a resolved phylogeny and a scenario for the evolution of multicellularity in that clade are proposed.

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In flowering plants, strigolactones (SLs) have dual functions as hormones that regulate growth and development, and as rhizosphere signaling molecules that induce symbiosis with arbuscular mycorrhizal (AM) fungi. Here, we report the identification of bryosymbiol (BSB), an SL from the bryophyte Marchantia paleacea. BSB is also found in vascular plants, indicating its origin in the common ancestor of land plants.

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Objectives: Guided by the social ecological model, this study aimed to examine the relations of built environments (i.e., walking/cycling infrastructure, recreation facilities, neighborhood safety/crime), youth's transition abilities, and changes of youth's physical activity (PA) and play behaviors due to COVID-19-based restrictions.

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Plants display a tremendous diversity of developmental and physiological features, resulting from gains and losses of functional innovations across the plant phylogeny. Among those, the most impactful have been undoubtedly the ones that allowed plant terrestrializations, the transitions from an aquatic to a terrestrial environment. Although the embryophyte terrestrialization has been particularly scrutinized, others occurred across the plant phylogeny with the involvement of mutualistic symbioses as a common theme.

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