Publications by authors named "Perret S"

The continuous improvement of expression platforms is necessary to respond to the increasing demand for recombinant proteins that are required to carry out structural or functional studies as well as for their characterization as biotherapeutics. While transient gene expression (TGE) in mammalian cells constitutes a rapid and well-established approach, non-clonal stably transfected cells, or "pools," represent another option, which is especially attractive when recurring productions of the same protein are required. From a culture volume of just a few liters, stable pools can provide hundreds of milligrams to gram quantities of high-quality secreted recombinant proteins.

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Background: Xylans are polysaccharides that are naturally abundant in agricultural by-products, such as cereal brans and straws. Microbial degradation of arabinoxylan is facilitated by extracellular esterases that remove acetyl, feruloyl, and p-coumaroyl decorations. The bacterium Ruminiclostridium cellulolyticum possesses the Xua (xylan utilization associated) system, which is responsible for importing and intracellularly degrading arabinoxylodextrins.

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Providing human support for users of behavioral health technology can help facilitate the necessary engagement and clinical integration of digital tools in mental health care. A team conducted digital navigator training that taught participants how to promote patrons' digital literacy, evaluate and recommend health apps, and interpret smartphone data. The authors trained 80 participants from 21 organizations, demonstrating this training's feasibility, acceptability, and need.

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Arctic birds and mammals are physiologically adapted to survive in cold environments but live in the fastest warming region on the planet. They should therefore be most threatened by climate change. We fitted a phylogenetic model of upper critical temperature () in 255 bird species and determined that for dovekies (; 22.

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Mercury (Hg) is a metallic trace element toxic for humans and wildlife that can originate from natural and anthropic sources. Hg spatial gradients have been found in seabirds from the Arctic and other oceans, suggesting contrasting toxicity risks across regions. Selenium (Se) plays a protective role against Hg toxicity, but its spatial distribution has been much less investigated than that of Hg.

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Background: As healthcare continues to expand online and digital care offerings multiply, the importance of digital inclusion and equity is now better recognized. Yet despite impressive regional grassroots efforts, today there remain few readily deployable programs designed to support patient digital literacy.

Methods: Digital Outreach for Obtaining Resources and Skills (DOORs) is one such digital literacy program that has evolved over the last 5 years to meet the rising demand.

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As the number and availability of digital mental health tools increases, patients and clinicians see benefit only when these tools are engaging and well integrated into care. Digital navigators-ie, members of health-care teams who are dedicated to supporting patient use of digital resources-offer one solution and continue to be piloted in behavioural health; however, little is known about the core features of this position. The aims of this systematic review were to assess how digital navigators are implemented in behavioural health, and to provide a standardised definition of this position.

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Glycosylation is a key quality attribute that must be closely monitored for protein therapeutics. Established assays such as HILIC-Fld of released glycans and LC-MS of glycopeptides work well for glycoproteins with a few glycosylation sites but are less amenable for those with multiple glycosylation sites, resulting in complex datasets that are time consuming to generate and difficult to analyze. As part of efforts to improve preparedness for future pandemics, researchers are currently assessing where time can be saved in the vaccine development and production process.

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Article Synopsis
  • Cellobiose is taken up by the CuaABC transporter and broken down by the enzyme CbpA; genes for these proteins are crucial for using cellobiose and cellulose.
  • A second solute-binding protein, CuaD, works with a regulatory system CuaSR, forming a three-component system that enhances growth on cellobiose and cellulose.
  • Research indicates that both CuaDSR and CuaSR can respond to cellobiose, but CuaDSR is more effective at utilizing these sugar sources, likely due to CuaD's high affinity for cellobiose.
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Article Synopsis
  • Protein expression from stably transfected CHO clones is traditionally time-consuming for making therapeutic proteins, but newer methods like stable pools have improved significantly in speed and productivity.
  • Researchers have found that stable pools can produce high-quality SARS-CoV-2 spike proteins comparable to traditional clones in just weeks, rather than months.
  • The study suggests updating regulatory guidelines to allow the use of CHO pools for rapid development of clinical trial materials, especially important during urgent situations like pandemics.
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Climate change is transforming bioenergetic landscapes, challenging behavioral and physiological coping mechanisms. A critical question involves whether animals can adjust behavioral patterns and energy expenditure to stabilize fitness given reconfiguration of resource bases, or whether limits to plasticity ultimately compromise energy balance. In the Arctic, rapidly warming temperatures are transforming food webs, making Arctic organisms strong models for understanding biological implications of climate change-related environmental variability.

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Postpartum mental health conditions are a public health concern, affecting a large number of reproductive-age women and their families. Postpartum depression alone affects at least 14% of new mothers and their families. However, very little has been written about how advances in digital mental health can benefit women in the postpartum period, or how those advances may poorly serve this vulnerable population.

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Combined effects of multiple, climate change-associated stressors are of mounting concern, especially in Arctic ecosystems. Elevated mercury (Hg) exposure in Arctic animals could affect behavioral responses to changes in foraging landscapes caused by climate change, generating interactive effects on behavior and population resilience. We investigated this hypothesis in little auks (), a keystone Arctic seabird.

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Many animals migrate after reproduction to respond to seasonal environmental changes. Environmental conditions experienced on non-breeding sites can have carryover effects on fitness. Exposure to harmful chemicals can vary widely between breeding and non-breeding grounds, but its carryover effects are poorly studied.

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Background: Primary degraders of polysaccharides play a key role in anaerobic biotopes, where plant cell wall accumulates, providing extracellular enzymes to release fermentable carbohydrates to fuel themselves and other non-degrader species. Ruminiclostridium cellulolyticum is a model primary degrader growing amongst others on arabinoxylan. It produces large multi-enzymatic complexes called cellulosomes, which efficiently deconstruct arabinoxylan into fermentable monosaccharides.

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Nanobodies offer several potential advantages over mAbs for the control of SARS-CoV-2. Their ability to access cryptic epitopes conserved across SARS-CoV-2 variants of concern (VoCs) and feasibility to engineer modular, multimeric designs, make these antibody fragments ideal candidates for developing broad-spectrum therapeutics against current and continually emerging SARS-CoV-2 VoCs. Here we describe a diverse collection of 37 anti-SARS-CoV-2 spike glycoprotein nanobodies extensively characterized as both monovalent and IgG Fc-fused bivalent modalities.

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Rechargeable lithium-ion batteries (LIB) play a key role in the energy transition towards clean energy, powering electric vehicles, storing energy on renewable grids, and helping to cut emissions from transportation and energy sectors. Lithium (Li) demand is estimated to increase considerably in the near future, due to the growing need for clean-energy technologies. The corollary is that consumer expectations will also grow in terms of guarantees on the origin of Li and the efforts made to reduce the environmental and social impact potentially associated with its extraction.

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Accelerometry has been widely used to estimate energy expenditure in a broad array of terrestrial and aquatic species. However, a recent reappraisal of the method showed that relationships between dynamic body acceleration (DBA) and energy expenditure weaken as the proportion of non-mechanical costs increases. Aquatic air breathing species often exemplify this pattern, as buoyancy, thermoregulation and other physiological mechanisms disproportionately affect oxygen consumption during dives.

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Urbanisation is a world-wide phenomenon converting natural habitats into new artificial ones. Environmental conditions associated with urbanisation represent great challenges for wildlife. Behaviour and stress tolerance are considered of major importance in the adaptation to novel urban habitats and numerous studies already reported behavioural and stress response phenotypes associated with urbanisation, often suggesting they represented adaptations, while rarely demonstrating it.

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Some effector functions prompted by immunoglobulin G (IgG) antibodies, such as antibody-dependent cell-mediated cytotoxicity (ADCC), strongly depend on the N-glycans linked to asparagine 297 of the Fc region of the protein. A single α-(1,6)-fucosyltransferase (FUT8) is responsible for catalyzing the addition of an α-1,6-linked fucose residue to the first GlcNAc residue of the N-linked glycans. Antibodies missing this core fucose show a significantly enhanced ADCC and increased antitumor activity, which could help reduce therapeutic dose requirement, potentially translating into reduced safety concerns and manufacturing costs.

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Xyloglucan utilization by was formerly shown to imply the uptake of large xylogluco-oligosaccharides, followed by cytosolic depolymerization into glucose, galactose, xylose, and cellobiose. This raises the question of how the anaerobic bacterium manages the simultaneous presence of multiple sugars. Using genetic and biochemical approaches targeting the corresponding metabolic pathways, we observed that, surprisingly, all sugars are catabolized, collectively, but glucose consumption is prioritized.

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We review recent studies of cavity switching induced by the optical injection of free carriers in micropillar cavities containing quantum dots. Using the quantum dots as a broadband internal light source and a streak camera as detector, we track the resonance frequencies for a large set of modes with picosecond time resolution. We report a record-fast switch-on time constant (1.

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Rapid life-history changes caused by size-selective harvesting are often interpreted as a response to direct harvest selection against a large body size. However, similar trait changes may result from a harvest-induced relaxation of natural selection for a large body size via density-dependent selection. Here, we show evidence of such density-dependent selection favouring large-bodied individuals at high population densities, in replicated pond populations of medaka fish.

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