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Dendrimers and supramolecular chemistry continue to fascinate researchers due to the endless unrevealed potential of their combination. This study investigates the self-assembly process of a series of hydrophobic triazolylferrocenyl dendrimers in aqueous medium. Deep investigation through NMR spectroscopy, absorption UV-vis spectroscopy along with theoretical simulations demonstrates that the ferrocenyl moieties interact intramolecularly and intermolecularly driving the self-assembly process. Data obtained by DLS, NTA, SEM, TEM, and EF-TEM demonstrate that these dendrimers, in water, spontaneously self-assemble through a hierarchical process. The dendrimers first self-assemble into uniform nanovesicles, which in turn self-assemble into larger vesosomes. The resulting vesosomes emit green non-traditional intrinsic fluorescence, which is a property that emerged from the self-assembled architectures. The vesosomes are efficiently uptaken by cancer cells and induce significant cytotoxic activity against the cancer cell line MCF-7, up to the submicromolar concentration. Positive dendritic effects are identified in the fluorescence intensity and in the cytotoxic activity of the vesosomes, which follow the trend G0-9Fc < G1-27Fc < G2-81Fc. This work showcases the remarkable potential of combining the two dynamic fields of dendrimers and supramolecular chemistry, which resulted in green fluorescent vesosomes capable of performing the dual role of cell imaging and killing, with potential applications in nanotheranostics., (© 2024 Wiley‐VCH GmbH.)

The Cu-glutathione (GSH) redox system, essential in biology, is designed here as a supramacromolecular assembly in which the tetrahedral 18e Cu(I) center loses a thiol ligand upon adsorption onto ZIF-8, as shown by EXAFS and DFT calculation, to generate a very robust 16e planar trigonal single-atom Cu(I) catalyst. Synergy between Cu(I) and ZIF-8, revealed by catalytic experiments and DFT calculation, affords CO 2 conversion into high-value-added chemicals with a wide scope of substrates by reaction with terminal alkynes or propargyl amines in excellent yields under mild conditions and reuse at least 10 times without significant decrease in catalytic efficiency., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

In this mini-review article the concept of electron reservoir materials developed in the author's laboratory is summarized. Starting from mono- and bimetallic electron reservoir complexes and their electronic and catalytic properties this concept extends to macromolecular electron-reservoir devices including metallodendrimers, metallopolymers and macromolecule-stabilized late transition-metal nanoparticles. The electronic switch in these devices is discussed as well as the structure-dependent possibilities to stabilize both utilized redox forms. Catalytic and energy-related applications involving redox metallomacromolecules and nanoparticles and their potential extension are briefly discussed. Giant ferrocene and pentamethylferrocene-based dendrimers and polymers are typical electron reservoir macromolecules that have been isolated in both oxidized and reduced forms with the ability to carry a large flow of electrons at about the same potential. The dramatic structural and size changes of the metallomacromolecules upon redox switch is reminiscent of molecular machines. [ABSTRACT FROM AUTHOR]

This study explores the stabilization by niobic acid, of Pt, Ni, Pd, and Au nanoparticles (NPs) for the efficient microheterogeneous catalysis of NaBH 4 hydrolysis for hydrogen production. Niobic acid is the most widely studied Nb 2 O 5 polymorph, and it is employed here for the first time for this key reaction relevant to green energy. Structural insights from XRD, Raman, and FTIR spectroscopies, combined with hydrogen production data, reveal the role of niobic acid's Brønsted acidity in its catalytic activity. The supported NPs showed significantly higher efficiency than the non-supported counterparts regarding turnover frequency, average hydrogen production rate, and cost. Among the tested NPs, PtNPs and NiNPs demonstrate the most favorable results. The data imply mechanism changes during the reaction, and the kinetic isotope assay indicates a primary isotope effect. Reusability assays demonstrate consistent yields over five cycles for PtNPs, although catalytic efficiency decreases, likely due to the formation of reaction byproducts., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Electrocatalytic transformation of CO 2 to various syngas compositions is an exceedingly attractive approach to carbon-neutral recycling. Meanwhile, the achievement of selectivity, stability, and tunability of product ratios using single-component electrocatalysts is challenging. Herein, the theoretically-assisted design of the triple-component nanocomposite electrocatalyst Cu 10 Sn 3 -Cu-SnO x that addresses this challenge is presented. It is shown that Cu 10 Sn 3 is a valuable electrocatalyst for suitable CO 2 reduction to CO, SnO 2 for CO 2 reduction to formate at large overpotentials, and that the Cu-SnO 2 interface facilitates H 2 evolution. Accordingly, the interaction between the three functional components affords tunable CO/H 2 ratios, from 1:2 to 2:1, of the produced syngas by controlling the applied potentials and relative contents of functional components. The syngas generation is selective (Faradaic efficiency, FE = 100%) at relatively lower cathodic potentials, whereas formate is the only liquid product detected at relatively higher cathodic potentials. The theoretically guided design approach therefore provides a new opportunity to boost the selectivity and stability of CO 2 reduction to tunable syngas., (© 2023 Wiley‐VCH GmbH.)

Unsaturated furanic aldehydes are derived from lignocellulosic biomass resources and subsequently used to produce valuable chemicals. However, the highly efficient, selective hydrogenation of the biomass-derived unsaturated furan CO bond remains challenging. Here we report that graphene-like nitrogen doped porous carbon (GNPC) nanosheets are synthesized from carbon-rich, sustainable, and renewable biomass precursors (glucose, fructose and 5-hydroxymethylfurfural, HMF) with high surface areas, large pore volumes and narrow mesopores. GNPC derived from HMF is an excellent catalyst support for PtCo nanoparticles with ultrafine nanoparticles size and homogeneous distributions. This catalyst is highly efficient for hydrogenation of biomass-derived furan-based unsaturated aldehydes, with high yields, to the corresponding unsaturated alcohols under mild conditions. This design strategy should further allow the development of selective, simple, green heterogeneous catalysts for challenging chemical transformations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Approximately 20% of neonates with congenital cytomegalovirus (cCMV) develop long-term sequelae. The ability to accurately predict long-term outcomes as early as the neonatal period would help to provide for appropriate parental counseling and treatment indications. With this study, we aimed to identify neonatal predictive markers of cCMV long-term outcomes., Methods: As this study's subjects, we chose neonates diagnosed with cCMV in 13 hospitals throughout France recruited from 2013 to 2017 and evaluated for at least 2 years with thorough clinical, audiology, and imaging evaluations and psychomotor development tests., Results: A total of 253 neonates were included, and 3 were later excluded because of the identification of a genetic disorder. A total of 227 were followed up for 2 years: 187/227 (82%) and 34/227 (15%) were infected after a maternal primary or nonprimary infection, respectively, 91/227 (40%) were symptomatic at birth, and 44/227 (19%) had cCMV sequelae. Maternal primary infection in the first trimester was the strongest prognosis factor (odds ratio = 38.34 [95% confidence interval, 5.02-293], P < .001). A predictive model of no risk of sequelae at 2 years of age according to normal hearing loss at birth, normal cerebral ultrasound, and normal platelet count had 98% specificity, 69% sensitivity, and 0.89 area under the curve (95% confidence interval, 0.83-0.96)., Conclusions: In the studied population, children with normal hearing at birth, normal platelet count at birth, and a normal cranial ultrasound had no risk of neurologic sequelae and a low risk of delayed unilateral sensorineural hearing loss. The use of this model based on readily available neonatal markers should help clinicians establish a personalized care pathway for each cCMV neonate., (Copyright © 2024 by the American Academy of Pediatrics.)

Lignin, the most abundant natural material, is considered as a low-value commercial biomass waste from paper mills and wineries. In an effort to turn biomass waste into a highly valuable material, herein, a new-type of hollow carbon nanospheres (HCNs) is designed and synthesized by pyrolysis of biomass dealkali lignin, as an efficient nanocatalyst for the elimination of antibiotics in complex water matrices. Detailed characterization shows that HCNs possess a hollow nanosphere structure, with abundant graphitic C/N and surface N and O-containing functional groups favorable for peroxydisulfate (PDS) activation. Among them, HCN-500 provides the maximum degradation rate (95.0%) and mineralization efficiency (74.4%) surpassing those of most metal-based advanced oxidation processes (AOPs) in the elimination of oxytetracycline (OTC). Density functional theory (DFT) calculations and high-resolution mass spectroscopy (HR-MS) were employed to reveal the possible degradation pathway of OTC elimination. In addition, the HCN-500/PDS system is also successfully applied to real antibiotics removal in complex water matrices ( e.g. river water and tap water), with excellent catalytic performances., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

Aim: Very preterm infants are exposed to an atypical environment that could alter their developmental trajectory. We aimed to examine neonatal imitation, a foundation of social cognition, in very preterm and full-term infants., Methods: In Strasbourg, France, between 2015 and 2018, we prospectively investigated the development of imitation skills. Very preterm (27 to 33 weeks of gestational age, n = 20) and full-term infants (n = 20) were enrolled using four gestures: tongue protrusion, mouth opening, sequential finger movements and hand movements. All testing were performed in infants at term-equivalent age. Two independent and blinded observers coded the behaviour of each infant on video recording. Facial expressions or hand movements, similar to the one presented, were quantified and classified according to their timing., Results: A total of 37 out of 40 infants imitated at least one gesture. The very preterm and term infants did not differ in the presence of imitation or its timing for the four gestures tested. The very preterm infants displayed more imitation abilities for sequential finger movement. Tongue protrusion and sequential finger movement were the particularly strong imitated gesture in both groups., Conclusion: These findings are the first to show similar neonatal imitation in term and very preterm infants. Our results may support early parent-infant social interactions., (©2021 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.)

Palladium is one of the most utilized metals in catalysis, particularly for hydrogenation and oxidation, cross C–C coupling, hydrogen formation, photocatalytic and electrocatalytic energy conversion reactions. Heterogeneous catalysis is undergoing a considerable move involving molecular aspects, which allows a better control and understanding of the structure–reactivity relationship toward optimization of the catalyst performances and selectivities. Inspired by organometallic catalysis, nanocatalytic materials that provide heterogeneization, nanocatalyst stabilization and optimized synergies include iron oxides, polymers, dendrimers, magnetic iron oxides, metal–organic and covalent-organic frameworks, carbons, atomically precise nanoclusters and other subnanoclusters such as single atoms, dual atoms and their combination and synergies with nanoparticles. In these nanocomposites, the number of catalytically utilized expansive Pd atoms is minimized. This mini-review addresses new trends of Pd nanocatalysis including these aspects with selected examples and examines perspectives. Progress of Pd nanocatalysis are reviewed including dramatic recent decrease of Pd sub-nanoparticle size utilizing modern organic or inorganic framework matrices. [ABSTRACT FROM AUTHOR]

Ferrocene has been the most used organometallic moiety introduced in organic and bioinorganic drugs to cure cancers and various other diseases. Following several pioneering studies, two real breakthroughs occurred in 1996 and 1997. In 1996, Jaouen et al. reported ferrocifens, ferrocene analogs of tamoxifen, the chemotherapeutic for hormone-dependent breast cancer. Several ferrocifens are now in preclinical evaluation. Independently, in 1997, ferroquine, an analog of the antimalarial drug chloroquine upon the introduction of a ferrocenyl substituent in the carbon chain, was reported by the Biot-Brocard group and found to be active against both chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum . Ferroquine, in combination with artefenomel, completed phase IIb clinical evaluation in 2019. More than 1000 studies have been published on ferrocenyl-containing pharmacophores against infectious diseases, including parasitic, bacterial, fungal, and viral infections, but the relationship between structure and biological activity has been scarcely demonstrated, unlike for ferrocifens and ferroquines. In a majority of ferrocene-containing drugs, however, the production of reactive oxygen species (ROS), in particular the OH. radical, produced by Fenton catalysis, plays a key role and is scrutinized in this mini-review, together with the supramolecular approach utilizing drug delivery nanosystems, such as micelles, metal-organic frameworks (MOFs), polymers, and dendrimers.

This review links various areas of inorganic chemistry around the themes developed by our research group during the last four decades. It is firstly based on the electronic structure of iron sandwich complexes, showing how the metal electron count dictates their reactivities, with various applications ( via C-H activation, C-C bond formation) as reducing and oxidizing agents, redox and electrocatalysts and precursors of dendrimers and catalyst templates through bursting reactions. Various electron-transfer processes and consequences are explored, including the influence of the redox state on the acidity of robust ligands and the possibility to iterate in situ C-H activation and C-C bond formation to build arene-cored dendrimers. Examples of how these dendrimers are functionalized are illustrated using the cross olefin metathesis reactions, with application to the synthesis of soft nanomaterials and biomaterials. Mixed and average valence complexes give rise to remarkable subsequent organometallic reactions, including the salt influence on these reactions. The stereo-electronic aspect of these mixed valencies is pointed out in star-shaped multi-ferrocenes with a frustration effect and other multi-organoiron systems, with the perspective of understanding electron-transfer processes among dendrimer redox sites involving electrostatic effects and application to redox sensing and polymer metallocene batteries. Dendritic redox sensing is summarized for biologically relevant anions such as ATP 2- with supramolecular exoreceptor interactions at the dendrimer periphery in parallel with the seminal work on metallocene-derived endoreceptors by Beer's group. This aspect includes the design of the first metallodendrimers that have applications in both redox sensing and micellar catalysis with nanoparticles. These properties provide the opportunity to summarize the biomedical (mostly anticancer) applications of ferrocenes, dendrimers and dendritic ferrocenes in biomedicine (in particular the contribution from our group, but not only). Finally, the use of dendrimers as templates for catalysis is illustrated with numerous reactions including C-C bond formation, click reactions and H 2 production reactions.

Metallomacromolecules are frequently encountered in redox proteins including metal-tanned hide collagen and play crucial roles involving supramolecular properties in biological electron-transfer processes. They are also currently found in non-natural families, such as: metallopolymers, metallodendrimers and metallodendronic polymers. This mini-review discusses the supramolecular redox functions of such nanomaterials developed in our research group. Electron-transfer processes are first examined in mono-, bis- and hexa-nuclear ferrocenes and other electron-reservoir organoiron systems showing the influence of supramolecular and reorganization aspects on their mechanism. Then applications of electron-transfer processes using these same organoiron redox systems in metallomacromolecules and their supramolecular functions are discussed including redox recognition/sensing, catalysis templates, electrocatalysis, redox catalysis, molecular machines, electrochromes, drug delivery device and nanobatteries. [ABSTRACT FROM AUTHOR]

Hydrogen (H 2 ) generation and storage are actively investigated to provide a green source of energy, and formic acid (HCOOH), a major product obtained from the biomass, is regarded as a productive source of H 2 . Therefore, improvements in heterogeneous catalysts are called for. Here, a novel type of catalyst support is proposed involving simple addition of the mixture of metal ion precursors to core-shell ZIF-8@ZIF-67, followed by reduction with NaBH 4 , with performances surpassing those obtained using nanocatalysts in ZIF-8 or ZIF-67. The nanocatalysts Pd x Ag were optimized with ZIF-8@Pd 2 Ag 1 @ZIF-67 under visible-light illumination for selective HCOOH dehydrogenation involving a turnover frequency value of 430 h -1 under light irradiation at 353 K. These results also reveal the crucial roles of the Pd sites electronically promoted in the presence of visible light by the Ag plasmon resonance and the advantageous core-shell MOF structure. In order to examine the potential of extending this catalyst improvement principle to other catalytic reactions, 4-nitrophenol reduction, a benchmarking model of catalytic reaction, was tested, and the results also confirmed the superiority of the performance of ZIF-8@Pd 2 Ag 1 @ZIF-67 over Pd 2 Ag 1 @ZIF-8 and Pd 2 Ag 1 @ZIF-67, confirming the interest in the novel catalyst design.

Objectives: We aimed to evaluate (1) whether sedation analgesia (SA) used during therapeutic hypothermia (TH) was efficient to support the wellbeing of neonates with hypoxic-ischemic encephalopathy, (2) the SA level and its adjustment to clinical pain scores, and (3) the impact of inadequate SA on short-term neonatal outcomes evaluated at discharge., Methods: This was an observational retrospective study performed between 2011 and 2018 in two level III centers in Alsace, France. We analyzed the wellbeing of infants by using the COMFORT-Behavior (COMFORT-B) clinical score and SA level during TH, according to which we classified infants into four groups: those with excess SA, adequate SA, lack of SA, and variability of SA. We analyzed the variations in doses of SA and their justification. We also determined the impact of inadequate SA on neonatal outcomes at discharge by multivariate analyses with multinomial regression, with adequate SA as the reference., Results: A total of 110 patients were included, 89 from Strasbourg university hospital and 21 from Mulhouse hospital. The COMFORT-B score was assessed 95.5% of the time. Lack of SA was mainly found on the first day of TH (15/110, 14%). In all, 62 of 110 (57%) infants were in excess of SA over the entire duration of TH. Most dose variations were related to clinical pain scores. Inadequate SA was associated with negative short-term consequences. Infants with excess of SA had a longer duration of mechanical ventilation [mean ratio 1.46, 95% confidence interval (CI), 1.13-1.89, p  = 0.005] and higher incidence of abnormal neurological examination at discharge (odds ratio 2.61, 95% CI, 1.10-6.18, p  = 0.029) than infants with adequate SA., Discussion: Adequate SA was not easy to achieve during TH. Close and regular monitoring of SA level may help achieve adequate SA. Excess of SA can be harmful for newborns with hypoxic-ischemic encephalopathy who are undergoing TH., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Nakhleh-Philippe, Zores, Stern-Delfils, Escande, Astruc, Severac and Kuhn.)

Objective: To evaluate cytomegalovirus (CMV) viral load dynamics in blood and saliva during the first 2 years of life in symptomatic and asymptomatic infected infants and to identify whether these kinetics could have practical clinical implications., Study Design: The Cymepedia cohort prospectively included 256 congenitally infected neonates followed for 2 years. Whole blood and saliva were collected at inclusion and months 4 and 12, and saliva at months 18 and 24. Real-time CMV polymerase chain reaction (PCR) was performed, results expressed as log 10 IU/mL in blood and in copies per milliliter in saliva., Results: Viral load in saliva progressively decreased from 7.5 log 10 at birth to 3.3 log 10 at month 24. CMV PCR in saliva was positive in 100% and 96% of infants at 6 and 12 months, respectively. In the first month of life, neonatal saliva viral load of less than 5 log 10 was related to a late CMV transplacental passage. Detection in blood was positive in 92% of neonates (147/159) in the first month of life. No viral load threshold values in blood or saliva could be associated with a high risk of sequelae. Neonatal blood viral load of less than 3 log 10 IU/mL had a 100% negative predictive value for long-term sequelae., Conclusions: Viral loads in blood and saliva by CMV PCR testing in congenital infection fall over the first 24 months. In this study of infants affected mainly after primary maternal infection during pregnancy, all salivary samples were positive in the first 6 months of life and sequelae were not seen in infants with neonatal blood viral load of less than 3 log 10 IU/mL., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Biomass valorization is essential, particularly in emerging countries. Here, hydrochar from arabica coffee straw was functionalized with a triazole group (HD-TRz) for use as a support of palladium nanoparticles (PdNPs-HD-TRz) applied in the Ullmann coupling reaction for the first time. It provided remarkably excellent selectivities, conversions at a temperature as low as 45 °C and catalyst recyclability, surpassing previous literature performances. Hydrochar was obtained by one-pot reaction via hydrothermal synthesis, using NaOH solution as activating agent and functionalized with a 1,3-triazole group by CuAAC "click" reaction. The PdNPs were prepared via reduction of hydrochar-bound Pd(II) using NaBH 4 . Hydrochar functionalization was monitored by infrared spectroscopy, and X-ray diffraction (XRD) allowed to observe carbon and palladium planes in hydrochar and PdNPs HD-TRz structures. The PdNPs presented a spherical shape with 2.1 ± 0.1 nm size, homogeneously distributed in the carbon coverslips. The HD-TRz-supported PdNPs were used as a catalyst in the Ullmann reaction of iodobenzene, using ethanol as solvent with 100% of conversion and 91% selectivity at 45 °C. The material was reused, presenting 100% of conversion and selectivities of 92, 84 and 73% for the 1st, 2nd and 3rd cycle, respectively. The scope of the reaction was expanded to other molecules showing the potential of this and other triazole-hydrochar-supported nanocatalysts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Atom-precise nanoclusters-metal-organic framework (APNC/MOF) composites, as bifunctional material with well-defined structures, have attracted considerable attention in recent years. Despite the progress made to date, there is an urgent need to develop a generic and scalable approach for all APNCs. Herein, the authors present the Exploiting Fracture Strategy (EFS) and successfully construct a super-stable bifunctional APNC/ZIF-8(300 °C) composite overcoming the limitations of previous strategies in selecting APNCs. The EFS utilizes the fracture of ZnN in ZIF-8 after annealing at 300 °C. This method is suitable for all kinds of S/P protected APNCs with different sizes, including uncharged clusters Au 1 Ag 39 , Ag 40 , negatively charged Au 12 Ag 32 , positively charged Ag 46 Au 24 , Au 4 Cu 4 and P-ligand-protected Pd 3 Cl. Importantly, the generated APNC/MOF show significantly improved performances, for example, the activities of Au 12 Ag 32 /ZIF-8(300°C), Au 4 Cu 4 /ZIF-8(300°C), and Au 1 Ag 39 /ZIF-8(300°C) in the corresponding reactions are higher than those of Au 12 Ag 32 , Au 4 Cu 4 , and Au 1 Ag 39 , respectively. In particular, Au 12 Ag 32 /ZIF-8(300 °C) shows higher activity than Au 12 Ag 32 @ZIF-8. Therefore, this work offers guidance for the design of bifunctional APNC/MOF composites with excellent optimization of properties and opens up new horizons for future related nanomaterial studies and nanocatalyst designs., (© 2022 Wiley-VCH GmbH.)

Although the chemistry of carbonyl-protected platinum nanoclusters is well established, their bonding mode remains poorly understood. In most of them, the average Pt oxidation state is zero or slightly negative, leading to the apparent average configuration 5d 10 6s ε ( ε = 0 or very small) and the apparent conclusion that metal-metal bonding cannot arise from the completely filled 5d shell nor from the empty (or almost empty) 6s orbitals. However, DFT calculations show in fact that in these species the actual average configuration is 5d 10- x 6s x , which provides to the whole cluster a significant total number of 6s electrons that ensures metal-metal bonding. This ("excited") average configuration is to be related to that of coinage metals in ligated group 11 nanoclusters ( n d 10 ( n + 1)s x ). Calculations show that metal-metal bonding in most of these platinum nanoclusters can be rationalized within the concepts of superatoms and supermolecules , in a similar way as for group 11 nanoclusters. The "excited" 5d 10- x 6s x configuration results from a level crossing between 5d combinations and 6s combinations, the former transferring their electrons to the latter. This level crossing, which does not exist in the bare Pt n clusters, is induced by the ligand shell, the role of which being thus not innocent with respect to metal-metal bonding.