Publications by authors named "Laurin M"

During embryogenesis, cells arrange into precise patterns that enable tissues and organs to develop specialized functions. Despite its critical importance, the molecular choreography behind these collective cellular behaviors remains elusive, posing a major challenge in developmental biology and limiting advances in regenerative medicine. By using the mouse hair follicle as a mini-organ system to study the formation of bud-like structures during embryonic development, our work uncovers a crucial role for the Rho GTPase regulator ARHGEF3 in hair follicle morphogenesis.

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  • This work challenges the classical view that thirst and sodium appetite are separate motivations, proposing instead that they are part of a single underlying motivation influenced by dehydration.
  • It introduces the concept of "intervenient variable" to explain how different types of dehydration (extracellular vs. intracellular) can trigger behavioral responses that are regulated by specific brain regions.
  • The study also draws parallels between the sodium appetite observed in rats and thirst-like behaviors in marine animals, suggesting a common ancestral origin for these motivations and their role in the adaptation of tetrapods moving from aquatic to terrestrial environments.
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Differences in the physical and behavioral attributes of prey are likely to impose disparate demands of force and speed on the jaws of a predator. Because of biomechanical trade-offs between force and speed, this presents an interesting conundrum for predators of diverse prey types. Loggerhead shrikes (Lanius ludovicianus) are medium-sized (∼50 g) passeriform birds that dispatch and feed on a variety of arthropod and vertebrate prey, primarily using their beaks.

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The subcellular distribution of the polarity protein Yurt (Yrt) is subjected to a spatio-temporal regulation in Drosophila melanogaster embryonic epithelia. After cellularization, Yrt binds to the lateral membrane of ectodermal cells and maintains this localization throughout embryogenesis. During terminal differentiation of the epidermis, Yrt accumulates at septate junctions and is also recruited to the apical domain.

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  • The Fossilized Birth-Death (FBD) process has been used to explore biodiversity evolution by creating models that utilize fossil ages to generate phylogenetic trees without needing divergence times.
  • *The researchers developed methods to evaluate hypotheses about diversification, such as detecting mass extinctions or changes in fossilization rates, by applying the skyline FBD model and estimating parameters using simulations.
  • *The study applies these methods to an updated dataset on Permo-Carboniferous synapsids to investigate biodiversity dynamics in specific clades and to determine support for previously suggested mass extinction events.
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  • - The study found that after appendectomy, humans may face higher risks of severe diarrhea from infections like salmonellosis and Clostridium difficile colitis, highlighting the appendix's protective role.
  • - An analysis of 1251 veterinary records from various primate species revealed that those with an appendix experienced a lower risk and delayed onset of severe diarrhea compared to species without one.
  • - Notably, none of the primates with an appendix developed appendicitis over a 20-year follow-up, reinforcing the idea that the appendix helps protect against diarrhea, similar to its suspected role in humans.
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During development, progenitors simultaneously activate one lineage while silencing another, a feature highly regulated in adult stem cells but derailed in cancers. Equipped to bind cognate motifs in closed chromatin, pioneer factors operate at these crossroads, but how they perform fate switching remains elusive. Here we tackle this question with SOX9, a master regulator that diverts embryonic epidermal stem cells (EpdSCs) into becoming hair follicle stem cells.

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  • Amniotes display diverse limb postures, with erect limbs seen in heavy mammals and good runners, while crouched limbs are found in organisms with more generalized movement; reptiles show various limb postures ranging from sprawling to semi-erect.* -
  • The transition from sprawling to erect limb postures occurred for both synapsids and reptiles during the Mesozoic Era, particularly among archosauriforms in the Triassic, although the timeline for synapsids is less well-defined.* -
  • This study investigates the connection between femoral posture and trabecular architecture in bones, revealing that body mass influences microanatomical features more than posture itself, and suggests that the trabecular network is not
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  • * Modern reptiles exhibit considerable diversity in locomotion and posture, but the evolutionary path to this variety, especially among extinct species like Euparkeria and Marasuchus, is still unclear.
  • * The study of bone microanatomy, particularly through femur cross-sections from various reptiles, can help clarify locomotion and posture in extinct species, revealing reliable insights into their movement patterns and evolutionary transitions.
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The study of development is critical for revealing the evolution of major vertebrate lineages. Coelacanths have one of the longest evolutionary histories among osteichthyans, but despite access to extant representatives, the onset of their weakly ossified endoskeleton is still poorly understood. Here we present the first palaeohistological and skeletochronological study of from the Upper Devonian of Canada, pivotal for exploring the palaeobiology and early evolution of osteogenesis in coelacanths.

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Background: Botulinum toxin A (BTX-A) has a variety of uses in medicine. Some evidence suggests that intracavernosal (ic) BTX-A injection administered in addition to phosphodiesterase type 5 inhibitors (PDE5-Is) could effectively treat erectile dysfunction (ED) in insufficient responders to PDE5-Is.

Aim: To provide experimental pharmacological evidence for the use of onabotulinumtoxinA ic alone or in combination with PDE5-Is for difficult-to-treat ED.

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  • Researchers present a new method to calculate extinction times for extinct or mixed taxa using the Fossilized-Birth-Death model, improving on previous methods by considering diversification before extinction and examining the entire phylogenetic tree instead of each branch separately.
  • This approach allows for estimating extinction times for lineages with only one fossil if they belong to a broader group with multiple fossil records, leading to more accurate results.
  • The method was tested on three synapsid taxa from the Permo-Carboniferous era, revealing that their extinction aligns with a gradual decline in biodiversity during the late Kungurian/early Roadian period.
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  • Pachyosteosclerosis is a condition that leads to the development of dense and bulky bones, typically seen in early aquatic animals like whales and dolphins, but usually decreases as their swimming ability improves.
  • In the Miocene era, this condition re-emerged in seals, dolphins, and whales from the Paratethys Sea due to changes in bone remodeling during a period of hypersaline conditions.
  • The presence of dense bones likely served as ballast, helping these animals swim more efficiently in the denser waters, and from this region, the trait spread eastward, becoming prominent in late Miocene whale species.
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Skin cancers are the most common cancers worldwide. Among them, melanoma, basal cell carcinoma of the skin and cutaneous squamous cell carcinoma are the three major subtypes. These cancers are characterized by different genetic perturbations even though they are similarly caused by a lifelong exposure to the sun.

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The cecal appendix had been considered as a useless vestige since Darwin's work, but recent research questioned this idea demonstrating that the cecal appendix appeared among the mammals at least 80 million years ago and has made multiple and independent appearances without any obvious correlation with diet, social life, ecology, or size of the cecum. However, functions and probable selective advantage conferred by this anatomical structure still remain enigmatic. We found, through analyses of data on 258 mammalian species, that cecal appendix presence is correlated with increased maximal observed longevity.

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The Mediterranean fruit fly, (Wied.), is an endemic pest in fruit-growing areas of the Spanish Mediterranean coast. In the Valencian Community, it represents a serious problem in the cultivation of citrus and numerous species of fruit, such as peach, cherry, apricot, persimmon, etc.

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  • Coelacanths have been considered evolutionarily stable for over 400 million years, but new fossil finds challenge this view by showing some unusual variations in their morphology, especially in their dermal skeletons.
  • A study of the scales from the fossil Miguashaia bureaui, found in Canada, provides detailed histological insights and reveals characteristics reminiscent of ancient fish, indicating significant complexity in their development.
  • The findings support the idea that coelacanths have undergone subtle changes over time rather than remaining entirely unchanged, highlighting both their evolutionary history and the importance of their dermal structures.
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  • The study focuses on the Bursidae family of "frog shells," highlighting their diversity, particularly in the Indo-West Pacific, with 59 recent species identified.
  • Researchers sequenced genetic markers from over 30 species to analyze their evolutionary relationships, discovering that while Bursidae is monophyletic, the genus Bursa is polyphyletic.
  • New genera were established and identified, and a dating analysis suggests that the group's diversification is connected to tectonic events that shifted biodiversity from the western Tethys to the Indo-Pacific.
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Background: The main purpose of this study is to investigate the effect of silodosin on the urodynamic consequences in a previously established model of lower urinary tract symptoms associated with benign prostate hyperplasia, the spontaneously hypertensive rats (SHR) supplemented with testosterone.

Methods: Three groups of animals (8-week-old; n = 10/group) were considered: Wistar Kyoto (control) rats (WKY), SHR supplemented with testosterone at 3 mg/kg/day and treated with either vehicle (SHR-T, n = 10) or silodosin at 0.1 mg/kg/day (SHR-T + silodosin, n = 10) by oral gavage for 6 weeks.

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Since their discovery, Rho GTPases have emerged as key regulators of cytoskeletal dynamics. In humans, there are 20 Rho GTPases and more than 150 regulators that belong to the RhoGEF, RhoGAP, and RhoGDI families. Throughout development, Rho GTPases choregraph a plethora of cellular processes essential for cellular migration, cell-cell junctions, and cell polarity assembly.

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  • The study introduces a method to calculate the exact probability distribution of divergence times in a phylogenetic tree using only fossil ages, particularly under the Fossilized Birth-Death model.
  • It specifically focuses on determining the age of Amniota, revealing it to be approximately 322 to 340 million years ago, which is older than the previously assumed range of 310-315 million years.
  • This research is significant as it not only revises the timeline for key evolutionary events but also presents a new technique to understand the probability density of divergence times in evolutionary studies.
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  • Genome size has been thought to influence metabolic rate in animals through the nucleotypic effect, but recent studies show little evidence supporting this connection.
  • Analysis of various vertebrates reveals that body mass is the stronger predictor of metabolic rate, with notable differences between warm-blooded (endothermic) and cold-blooded (ectothermic) animals.
  • While some cellular effects of genome size may exist, the data largely indicates that there isn't a significant functional link between genome size and basal metabolic rate among modern vertebrates.
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  • The amniotic egg is crucial in vertebrate evolution, influencing the development of amniotes, which are a group of vertebrates that includes mammals, birds, and reptiles.
  • Researchers tested Carroll's 1970 theory about the egg's origin using a new method that assesses different evolutionary trends by splitting phylogenetic trees at various nodes.
  • Their findings showed that the expected significant changes in body size evolution along the amniote stem were not present, challenging the validity of Carroll's scenario.
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