3D Printed Bioplastics with Shape-Memory Behavior Based on Native Bovine Serum Albumin

Unformatted postprintBio-based plastics that can supplant petroleum-derived materials are necessary to meet the future demands of sustainability in the life cycle of plastic materials. While there are significant efforts to develop protein-based plastic materials for commercial use, their application is limited by poor processability and limitations in mechanical performance. Here, we present a bovine serum albumin (BSA)-based resin for stereolithographic apparatus (SLA) 3D printing that affords bioplastic objects with shape memory behavior. We demonstrate that the native conformation of these globular proteins is largely retained in the 3D printed constructs, and that each protein molecule possesses a “stored length” that could be revealed during mechanical deformation (extension or compression) of the 3D bioplastic objects. While the plastically deformed objects could retain this state for an indefinite period of time, heating the object or submerging in water allowed it to return to its original 3D printed shape.We thank the Center for Research in Education and Simulation Technologies (CREST) at The University of Washington, and in particular Alex Gong for his assistance during the tensile tests. E.S.-R. thanks the European funding by the Marie Sklodowska-Curie Individual Fellowships (MSCA-IF-GF) 841879-4D Biogel. H.S. and A.G.-L. thank MINECO for funding through MAT2017-83373-R. A.N. thanks the National Science Foundation for support (1752972). A.L.C. thanks the European Research Council ERC-CoG-648071-ProNANO, and Agencia Estatal de Investigación, Spain (PID2019-111649RB-I00). This work was performed partially under the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency – Grant No. MDM-2017-0720 (CIC biomaGUNE)

Engineering conductive protein films through nanoscale self-assembly and gold nanoparticles doping

Protein-based materials are usually considered as insulators, although conductivity has been recently shown in proteins. This fact opens the door to develop new biocompatible conductive materials. While there are emerging efforts in this area, there is an open challenge related to the limited conductivity of protein-based systems. This work shows a novel approach to tune the charge transport properties of protein-based materials by using electron-dense AuNPs. Two strategies are combined in a unique way to generate the conductive solid films: (1) the controlled self-assembly of a protein building block; (2) the templating of AuNPs by the engineered building block. This bottom-up approach allows controlling the structure of the films and the distribution of the AuNPs within, leading to enhanced conductivity. This work illustrates a promising strategy for the development of effective hybrid protein-based bioelectrical materialsThis work was partially supported by the European Research Council ERC-CoG-648071-ProNANO, ERC-PoC-841063-NIMM, Agencia Estatal de Investigación, Spain (PID2019- 111649RB-I00; and MAT2017-88693-R), and the Basque Government (Elkartek KK-2017/00008), E.L-M thanks the Spanish Ministry of Science and Innovation for the FPI grant (BES-2017-079646). This work was performed under the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency – Grant No. MDM-2017-0720 (CIC biomaGUNE) and SEV-2016-0686 (IMDEA Nanociencia

Multiple Changes in Peptide and Lipid Expression Associated with Regeneration in the Nervous System of the Medicinal Leech

peer reviewe

Auto-assemblage de nanoparticules métalliques et semi-conductrices dirigé par reconnaissance entre protéines artificielles

Nanoparticles self-assembly driven by biomolecules is a promising approach for developing nanostructured materials with new optical properties. The purpose of this work is the self-assembly of metal and semiconductor nanoparticles directed by artificial proteins called α-Repeat. For this purpose, semiconductor nanocrystals (CdSe/ZnS or CdSe/CdS) and spherical or anisotropic gold nanoparticles have been prepared. These nanoparticles have been functionalized with PEGylated peptide ligands providing them adequate colloidal stability while maintaining their optical properties. A functionalization strategy based on polycysteine and poly-histidine tags has allowed the proteins to be grafted onto the surface of inorganic nanoparticles. Nanoparticles functionalized with artificial proteins were then used for the self-assembly of semiconductor nanoparticles and hybrid self-assembly between semiconductor nanoparticles and metal nanoparticles. The structure study of self-assembled nanostructures has shown, in some cases, a very well defined sub-10 nm interparticle distance. Finally, the study of optical properties revealed very strong exciton-plasmon interactions induced by self-assembly. This self-assembling process strongly affected the emission properties of the semiconductor nanoparticles in hybrid ensembles.L’auto-assemblage de nanoparticules dirigé par des biomolécules constitue une approche prometteuse pour la mise au point de nanomatériaux structurés présentant des propriétés optiques collectives originales. L’objet de cette thèse concerne l’auto-assemblage de nanoparticules métalliques et semi-conductrices dirigé par des protéines artificielles appelées α-Repeat. Dans cette optique, des nanocristaux semi-conducteurs (CdSe/ZnS ou CdSe/CdS) et des nanoparticules d’or sphériques ou anisotropes ont été préparés. Ces nanoparticules ont été fonctionnalisées avec des ligands peptidiques PEGylés, qui leur confère une stabilité colloïdale satisfaisante tout en conservant leurs propriétés optiques. Une stratégie de fonctionnalisation basée sur des étiquettes d’affinité poly-cystéine et poly-histidine a permis de greffer les protéines sur la surface des nanoparticules inorganiques. Les nanoparticules ainsi fonctionnalisées avec les protéines artificielles ont ensuite été utilisées pour l’auto-assemblage de nanoparticules semi-conductrices et l’auto-assemblage hybride entre des nanoparticules semi-conductrices et des nanoparticules métalliques. L’étude structurale des ensembles obtenus a montré, dans certains cas, une interdistance bien définie et inférieure à 10 nm. Finalement, l’étude des propriétés optiques a révélé des transferts d’énergie non radiatifs entre nanoparticules semi-conductrices et nanoparticules métalliques, qui témoignent d’interactions exciton—plasmon très fortes induites par l’auto-assemblage

Metal and semiconductor nanoparticles self-assembly directed by recognition between artificial proteins

L’auto-assemblage de nanoparticules dirigé par des biomolécules constitue une approche prometteuse pour la mise au point de nanomatériaux structurés présentant des propriétés optiques collectives originales. L’objet de cette thèse concerne l’auto-assemblage de nanoparticules métalliques et semi-conductrices dirigé par des protéines artificielles appelées α-Repeat. Dans cette optique, des nanocristaux semi-conducteurs (CdSe/ZnS ou CdSe/CdS) et des nanoparticules d’or sphériques ou anisotropes ont été préparés. Ces nanoparticules ont été fonctionnalisées avec des ligands peptidiques PEGylés, qui leur confère une stabilité colloïdale satisfaisante tout en conservant leurs propriétés optiques. Une stratégie de fonctionnalisation basée sur des étiquettes d’affinité poly-cystéine et poly-histidine a permis de greffer les protéines sur la surface des nanoparticules inorganiques. Les nanoparticules ainsi fonctionnalisées avec les protéines artificielles ont ensuite été utilisées pour l’auto-assemblage de nanoparticules semi-conductrices et l’auto-assemblage hybride entre des nanoparticules semi-conductrices et des nanoparticules métalliques. L’étude structurale des ensembles obtenus a montré, dans certains cas, une interdistance bien définie et inférieure à 10 nm. Finalement, l’étude des propriétés optiques a révélé des transferts d’énergie non radiatifs entre nanoparticules semi-conductrices et nanoparticules métalliques, qui témoignent d’interactions exciton—plasmon très fortes induites par l’auto-assemblage.Nanoparticles self-assembly driven by biomolecules is a promising approach for developing nanostructured materials with new optical properties. The purpose of this work is the self-assembly of metal and semiconductor nanoparticles directed by artificial proteins called α-Repeat. For this purpose, semiconductor nanocrystals (CdSe/ZnS or CdSe/CdS) and spherical or anisotropic gold nanoparticles have been prepared. These nanoparticles have been functionalized with PEGylated peptide ligands providing them adequate colloidal stability while maintaining their optical properties. A functionalization strategy based on polycysteine and poly-histidine tags has allowed the proteins to be grafted onto the surface of inorganic nanoparticles. Nanoparticles functionalized with artificial proteins were then used for the self-assembly of semiconductor nanoparticles and hybrid self-assembly between semiconductor nanoparticles and metal nanoparticles. The structure study of self-assembled nanostructures has shown, in some cases, a very well defined sub-10 nm interparticle distance. Finally, the study of optical properties revealed very strong exciton-plasmon interactions induced by self-assembly. This self-assembling process strongly affected the emission properties of the semiconductor nanoparticles in hybrid ensembles

An Unsymmetrical, Push-Pull Porphyrazine for Dye-Sensitized Solar Cells

An unsymmetrical, push-pull porphyrazine derivative bearing an isoindole-4-carboxylic acid moiety (TT112) is synthesized and incorporated in a dye-sensitized solar cell (DSSC). The device, which constitutes the first example of a porphyrazine-sensitized solar cell, exhibits a maximum power conversion efficiency of 3.4 %

Engineering Proteins for PEDOT Dispersions: A New Horizon for Highly Mixed Ionic-Electronic Biocompatible Conducting Materials.

Publication status: PublishedPoly (3,4-ethylenedioxythiophene) (PEDOT) doped with polystyrene sulfonate (PSS) is the most used conducting polymer from energy to biomedical applications. Despite its exceptional properties, there is a need for developing new materials that can improve some of its inherent limitations, e.g., biocompatibility. In this context, doping PEDOT is propose with a robust recombinant protein with tunable properties, the consensus tetratricopeptide repeated protein (CTPR). The doping consists of an oxidative polymerization, where the PEDOT chains are stabilized by the negative charges of the CTPR protein. CTPR proteins are evaluated with three different lengths (3, 10, and 20 identical CTPR units) and optimized varied synthetic conditions. These findings revealed higher doping rate and oxidized state of the PEDOT chains when doped with the smallest scaffold (CTPR3). These PEDOT:CTPR hybrids possess ionic and electronic conductivity. Notably, PEDOT:CTPR3 displayed an electronic conductivity of 0.016 S cm-1 , higher than any other reported protein-doped PEDOT. This result places PEDOT:CTPR3 at the level of PEDOT-biopolymer hybrids, and brings it closer in performance to PEDOT:PSS gold standard. Furthermore, PEDOT:CTPR3 dispersion is successfully optimized for inkjet printing, preserving its electroactivity properties after printing. This approach opens the door to the use of these novel hybrids for bioelectronics

Hybrid gold nanoparticle-quantum dot self-assembled nanostructures driven by complementary artificial proteins

International audienceHybrid nanostructures are constructed by the direct coupling of fluorescent quantum dots and plasmonic gold nanoparticles.The self-assembly is directed by the strong affinity between two artificial α-Repeat proteins that are introduced in thecapping layers of the nanoparticles at a controlled surface density. The proteins have been engineered to exhibit a highmutual affinity, corresponding to a dissociation constant in the nanomolar range, which is conferred to the proteinfunctionalizedquantum dots and gold nanoparticles. Protein-mediated self-assembly is evidenced by Surface PlasmonResonance and gel electrophoresis. The size and the structure of colloidal superstructures of complementary nanoparticlesis analyzed by transmission electronic microscopy and small angle X-ray scattering. The size of the superstructures isdetermined by the number of proteins per nanoparticle. The well-defined geometry of the rigid protein complex sets a highlyuniform interparticle distance of 8 nm that affects the emission properties of the quantum dots in the hybrid ensembles.Our results open the route to the design of hybrid emitter-plasmon colloidal assemblies with controlled near-field couplingand better optical response

Hypertrophie bénigne de la prostate: Étude comparative des résultats de la résection transurétrale et de l’adénomectomie

Introduction : L‘Hypertrophie Bénigne de la Prostate (HBP) représente la tumeur bénigne la plus fréquente de l’homme âgé de plus de 50 ans. Plusieurs modalités thérapeutiques sont possibles. Nous avons proposé ici de comparer les résultats entre l’Adénomectomie Trans-Vésicale (ATV) et la Résection Transurétrale Prostatique (RTUP). Matériel et méthodes : Étude transversale analytique sur 86 patients traités au Service d’Urologie de l’Hôpital Central de Yaoundé pendant 2 ans, soit 43 patients pour chaque groupe. Les données sociodémographiques, cliniques et thérapeutiques ont été saisies sur CSPRO version 7.1, analysées sur SPSS version 21.0 et Excel 2016 avec la valeur significative de P ≤ 0,05. Résultats : La moyenne d’âge des patients était de 67 ans et l’indication opératoire était l’échec du traitement médical, la rétention d’urine, le volume de la prostate ≤ 80g et le choix de la technique chirurgicale. Le groupe des ATV enregistrait une durée d’intervention plus longue, une transfusion sanguine systématique, une durée de cathétérisme et d’hospitalisation plus longue que la RTUP. Par contre, on n’enregistrait pas de différence significative en termes de débit urinaire, le Score International des Symptômes de la Prostate (IPSS) et la Qualité de Vie (QV) entre les deux groupes. Conclusion: Comparer l’ATV à la RTUP dans notre travail s’accompagne d’une durée d’intervention plus longue, une transfusion sanguine systématique, une durée de cathétérisme et d’hospitalisation plus longue pour le premier; par contre, en termes de résultats fonctionnels, il ne semble pas avoir de différences significatives entre les deux techniques. La RTUP reste la technique de choix si plateau technique disponible.   English title: Benign prostatic hyperplasia: a comparative study of the results, transurethral resection and adenomectomy Introduction: Benign prostatic hyperplasia (BPH) is the most common benign tumor in men aged over 50. Several therapeutic modalities are possible. We proposed here to compare the results between Transvesical Adenomectomy (TVA) and Transurethral Prostatic Resection (TURP). Materials and methods. Analytical cross-sectional study of 86 patients treated at the Department of Urology of the Yaounde Central Hospital for 2 years that is 43 patients in each group. Sociodemographic, clinical and therapeutic data were entered on CSPRO version 7.1, analyzed on SPSS version 21.0 and Excel 2016 with the significant value of P≤ 0.05. Results. The average age of the patients was 67 years and the operative indication was the failure of medical treatment, urine retention, prostate volume ≤ 80g and choice of surgical technique. The TVA group recorded longer operative time, systematic blood transfusion, catheterization time, and hospitalization time than TURP. However, there was no significant difference in urine output, International Prostate Symptom Score (IPSS) and Quality of Life (QL) between the two groups. Conclusion. Comparing TVA to TURP in our work is accompanied by a longer intervention time, a systematic blood transfusion, a longer catheterization and hospitalization time for the first one; on the other hand, in terms of functional results, there seems to be no significant difference between the two groups. TURP remains the technique of choice if technical platform available

Perspectives d'émergence d'une filière forêt-chimie des extractibles Points de vue des acteurs du Nord-Est de la France et du Sud-Ouest de l'Allemagne

International audienceForest biomass can be the source of molecules of interest for the purpose of substituting or supplementing molecules derived from oil. As a result, an innovative conversion of wood extractives may well present an economic, social and environmental opportunity. The aim of our study is to better assess the prospects for the emergence of a new chemical conversion of wood and wood by-products in the Grand Est region basing ourselves on opinions and feelings of players in the forestry and forest-based industry and on the chemicals sector in this region and neighbouring ones. Our results pertain to three areas: forest industry corporate strategies for processing wood by-products, the perceptions players have of the emergence of a forest/extractive chemicals industry and of the prospects for such an industry to become established in the medium term. We naturally believe these results need to be more thoroughly researched so as to more precisely spell out the conditions for such an industry to be born.La biomasse forestière peut être une source de molécules d’intérêt dans le but de substituer ou de compléter les molécules pétro-sourcées. Par conséquent, une valorisation innovante des extractibles du bois semble être une opportunité économique, sociale et environnementale. L’objectif de notre étude est de mieux cerner les perspectives d’émergence d’une nouvelle valorisation chimique des connexes bois pour la région Grand Est, à partir des avis et ressentis des acteurs de la filière forêt-bois et de la valorisation chimique de cette région ainsi que de territoires voisins. Nos résultats se portent sur trois axes : les stratégies de valorisation des connexes des entreprises de la filière forêt-bois, les perceptions des acteurs sur l’émergence d’une filière forêt-chimie, et les perspectives de mise en place d’une telle filière à moyen terme. Nous conviendrons tout de même que les résultats doivent être approfondis dans le cadre de perspectives de recherche pour préciser les conditions de la mise en œuvre de cette filière