Nous parlerons dans cet article de l’expérience « pilote » sur notre intersecteur d’une unité de dépistage précoce de l’autisme et des troubles envahissants du développement (TED), destinée à ...dépister et évaluer des enfants âgés de moins de trois ans, afin de leur proposer le plus rapidement possible des soins adaptés. Dans un premier temps, nous exposerons les différents aspects du travail au sein de cette unité en abordant tout d’abord le travail de réseau, avec en amont, le partenariat avec les différentes structures dont les centres de PMI, et en aval, le partenariat avec les structures de soins qui prendront le relais de la prise en charge de ces enfants. Le travail d’évaluation proprement dit sera ensuite abordé et notre protocole détaillé. Dans un second temps, nous ferons part de réflexions cliniques issues de notre expérience et aborderons la question de l’annonce du diagnostic, de l’alliance et du processus thérapeutique. Ces réflexions seront suivies de vignettes cliniques qui permettront d’illustrer la dimension thérapeutique qui nous semble déjà à l’œuvre lors de cette phase d’évaluation.
In this article we will present our early detection local program of autism and invasive developmental disorders. It is to detect and evaluate children under the age of three, in order to propose proper treatment as quickly as possible. First of all we will present the different aspects of the program working within a network. On one side the collaboration with different structures such as the maternal and infant protection (PMI) and on the other the collaboration with institutions that will specifically take care of these children. The proper evaluation will be then explained and our methods will be further detailed. Secondly, we will share our clinical studies stemmed from our experience and will then consider diagnosis announcement, alliance and therapeutic process. This will then be followed by case studies that will highlight the therapeutic dimension, which already seems to exist in this evaluation phase.
Peptide–polymer conjugates (PPCs) are of particular interest in the development of responsive, adaptive, and interactive materials due to the benefits offered by combining both building blocks and ...components. This review presents pioneering work as well as recent advances in the design of peptide–polymer conjugates, with a specific focus on their thermoresponsive behavior. This unique class of materials has shown great promise in the development of supramolecular structures with physicochemical properties that are modulated using soft and biorthogonal external stimuli. The temperature-induced self-assembly of PPCs into various supramolecular architectures, gelation processes, and tuning of accessible processing parameters to biologically relevant temperature windows are described. The discussion covers the chemical design of the conjugates, the supramolecular driving forces involved, and the mutual influence of the polymer and peptide segments. Additionally, some selected examples for potential biomedical applications of thermoresponsive PPCs in tissue engineering, delivery systems, tumor therapy, and biosensing are highlighted, as well as perspectives on future challenges.
Triggered by raised environmental awareness and the rising requirements for sustainable polymers such as degradable or recyclable polymers, studies on ring-opening (co)polymerization (ROP/ROCP) of ...(bio-based) cyclic monomers (e.g., cyclic esters, lactides, epoxides etc.) have been booming in recent years. Renewable five-membered γ-butyrolactone (γBL) and derivatives would thus be a desirable feedstock to produce poly(γ-butyrolactone) (PγBL) and different (bio-based) functional polyesters. Their copolymerization with other cyclic monomers could also afford an alternative to tune the properties of the resulting materials. Although γBL was traditionally regarded “non-polymerizable”, some progresses were made recently concerning the ROP/ROCP of γBL and derivatives. More importantly, some polyesters could be totally depolymerized back to their monomers by thermal or chemical treatment. This review is specially focused on ROP of γ-lactones and their copolymerization with other cyclic monomers by different catalytic/initiating systems, including Lewis/Brønsted acids, organic bases and alkali metal compounds, organometallic compounds, and cooperative bicomponent catalytic systems. The depolymerization process of some obtained polyesters is also discussed.
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Among the polymer families, aliphatic polyesters stand out from this category thanks to their degradable and biocompatible properties. In particular, the γ‐lactones differ from other lactones by ...yielding polyesters that can be depolymerized back to the monomer and offer the advantage of counting various biobased monomers. As an example, α‐hydroxy‐γ‐butyrolactone (HBL) is a hydroxy‐functionalized monomer that can be obtained by a biological synthetic route from glucose. In this article, the ring‐opening copolymerization (ROCP) of HBL and l‐lactide (LLA) using t‐BuP4 as catalyst is investigated. The copolymerizations were conducted within a temperature range of 5–100°C, affording monomer conversions exceeding 80%. The characterization of the copolyesters revealed a branched structure consisting of different HBL patterns, including cyclic, linear, and branched motives. Performing a kinetic study of the copolymerization at room temperature provided a deeper understanding of the mechanism. By modulating the reaction parameters, copolymers of low molar masses with an HBL content of up to 33% were synthesized. High molar mass LLA/HBL‐based copolyesters, with Mw¯$$ \overline{\mathrm{Mw}} $$ up to 290,000 g/mol, were synthesized by a straightforward chain coupling reaction with a diisocyanate.
Alternaria dauci is a Dothideomycete fungus, causal agent of carrot leaf blight. As a member of the Alternaria genus, known to produce a lot of secondary metabolite toxins, A. dauci is also supposed ...to synthetize host specific and non-host specific toxins playing a crucial role in pathogenicity. This study provides the first reviewing of secondary metabolism genetic basis in the Alternaria genus by prediction of 55 different putative core genes. Interestingly, aldaulactone, a phytotoxic benzenediol lactone from A. dauci, was demonstrated as important in pathogenicity and in carrot partial resistance to this fungus. As nothing is known about aldaulactone biosynthesis, bioinformatic analyses on a publicly available A. dauci genome data set that were reassembled, thanks to a transcriptome data set described here, allowed to identify 19 putative secondary metabolism clusters. We exploited phylogeny to pinpoint cluster 8 as a candidate in aldaulactone biosynthesis. This cluster contains AdPKS7 and AdPKS8, homologs with genes encoding a reducing and a non-reducing polyketide synthase. Clusters containing such a pair of PKS genes have been identified in the biosynthesis of resorcylic acid lactones or dihydroxyphenylacetic acid lactones. AdPKS7 and AdPKS8 gene expression patterns correlated with aldaulactone production in different experimental conditions. The present results highly suggest that both genes are responsible for aldaulactone biosynthesis.
Organocatalysis has been widely developed over the past decades as an alternative to metal-based catalysis. The actual concerns have also promoted the development of sustainable and degradable ...polymers. In this context, γ-lactones are an interesting class of monomers that count many bio-based monomers, yielding polyesters that can be readily depolymerized. Also, the use of functional substituted lactones such as the α-hydroxy-γ-butyrolactone (HBL) affords polyesters with pendant groups offering possible postmodification reactions. This article focuses on the ring-opening copolymerization (ROCP) of α-hydroxy-γ-butyrolactone (HBL) and ε-caprolactone (ε-CL) in the presence of phosphazene P4 base (tert-BuP4) as catalyst. The bulk copolymerization at high temperature (80 °C) yielded fast kinetics (5 min) and high monomer conversions (98% for ε-CL; 88% for HBL) and molar masses (14900 g/mol with Đ = 3.8). A kinetics study at 80 °C revealed a partial HBL depolymerization over time. This phenomenon induced changes in the microstructures of the copolymers. Similar high conversions and molar masses could be also achieved at room temperature for 6 h without any depolymerization. Various monomer feed ratios were also evaluated affording copolyesters with up to 31% of incorporated HBL. In addition, DFT calculations with respect to the HBL homopolymerization revealed similar activation energies between different possible reactions, which include ring-opening polymerization, branching, and backbiting reactions.
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•ε-Caprolactone and biosourced α-hydroxy-γ-butyrolactone are copolymerized by ring-opening polymerization.•Functional and branched copolyesters with various compositions are ...obtained.•LaN(SiMe3)23 was used as a catalyst.
The growing awareness of environmental concerns and the fossil resources depletion have raised the need to develop sustainable and degradable polymers such as aliphatic polyesters. γ-Lactone-based polyesters are of great interest today due to their ability to depolymerize. The introduction of functional groups appeared also useful to tune the properties of such polyesters. This can be addressed by the use of functional monomers such as the sugar-based α-hydroxy-γ-butyrolactone (HBL). In this study, the synthesis of random copolyesters of HBL and ε-caprolactone (ε-CL) was investigated via ring-opening copolymerization in the presence of LaN(SiMe3)23 as a catalyst. High polymerization temperature (80 °C) was required for fast and high monomer conversions. The characterization of the copolyesters and kinetic investigations provided better insight into the polymerization mechanism and formation of various HBL monomer units (cyclic, linear and branched). LaN(SiMe3)23 catalyst afforded high HBL conversion ratio (over 85 %) for the copolymerization reaction enabling the synthesis of copolyesters with a ratio of HBL units ranging from 9 to 63 %.
•Diffusion-Weight Imaging (DWI) has been used to explore pediatric concussion outcomes but findings have been mixed.•We combine multiple DWI metrics using Linked Component Analysis to explore ...outcomes more consistently.•Our findings suggest that existing diffusion techniques may not be sufficient to detect changes in white matter microstructure in pediatric concussion.
Diffusion-Weight Imaging (DWI) is increasingly used to explore a range of outcomes in pediatric concussion, particularly the neurobiological underpinnings of symptom recovery. However, the DWI findings within the broader pediatric concussion literature are mixed, which can largely be explained by methodological heterogeneity. To address some of these limitations, the aim of the present study was to utilize internationally- recognized criteria for concussion and a consistent imaging timepoint to conduct a comprehensive, multi-parametric survey of white matter microstructure after concussion. Forty-three children presenting with concussion to the emergency department of a tertiary level pediatric hospital underwent neuroimaging and were classified as either normally recovering (n = 27), or delayed recovering (n = 14) based on their post-concussion symptoms at 2 weeks post-injury.We combined multiple DWI metrics across four modeling approaches using Linked Independent Component Analysis (LICA) to extract several independent patterns of covariation in tissue microstructure present in the study cohort. Our analysis did not identify significant differences between the symptomatic and asymptomatic groups and no component significantly predicted delayed recovery. If white matter microstructure changes are implicated in delayed recovery from concussion, these findings, alongside previous work, suggest that current diffusion techniques are insufficient to detect those changes at this time.
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