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Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pathologie infectieuse, Infectious diseases, ANTICORPS NATUREL, LYMPHOCYTE, NEURAMINIDASE, GRIPPE, ENZYME, IMMUNOLOGIE, NATURAL ANTIBODY, INFLUENZA, ENZYMES, IMMUNOLOGY, MICROBIOLOGIE, MICROBIOLOGY, and MICROBIOLOGIA

LE VIRUS GRIPPAL, VIVANT OU MORT, PROVOQUE UNE AUGMENTATION D'ANTICORPS DONNANT UNE REACTION CROISEE AVEC UN ANTIGENE PRESENT SUR LES LYMPHOCYTES HUMAINS TRAITES PAR NEURAMINIDASE.

Gas-separation polymer membranes display a characteristic permeability-selectivity trade-off that has limited their industrial use. The most comprehensive approach to improving performance is to devise strategies that simultaneously increase fractional free volume, narrow free volume distribution, and enhance sorption selectivity, but generalizable methods for such approaches are exceedingly rare. Here, we present an in situ crosslinking and solid-state deprotection method to access previously inaccessible sorption and diffusion characteristics in amine-functionalized polymers of intrinsic microporosity. Free volume element (FVE) size can be increased while preserving a narrow FVE distribution, enabling below-upper bound polymers to surpass the H 2 /N 2 , H 2 /CH 4 , and O 2 /N 2 upper bounds and improving CO 2 -based selectivities by 200 %. This approach can transform polymers into chemical analogues with improved performance, thereby overcoming traditional permeability-selectivity trade-offs.
(© 2020 Wiley-VCH GmbH.)

Non-porous small molecule adsorbents such as {[3,5-(CF 3 ) 2 Pz]Cu} 3 (where Pz=pyrazolate) are an emerging class of materials that display attractive features for ethene-ethane separation. This work examines the chemistry of fluorinated copper(I) pyrazolates {[3,5-(CF 3 ) 2 Pz]Cu} 3 and {[4-Br-3,5-(CF 3 ) 2 Pz]Cu} 3 with much larger 1-butene in both solution and solid state, and reports the isolation of rare 1-butene complexes of copper(I), {[3,5-(CF 3 ) 2 Pz]Cu(H 2 C=CHC 2 H 5 )} 2 and {[4-Br-3,5-(CF 3 ) 2 Pz]Cu(H 2 C=CHC 2 H 5 )} 2 and their structural, spectroscopic, and computational data. The copper-butene adduct formation in solution involves olefin-induced structural transformation of trinuclear copper(I) pyrazolates to dinuclear mixed-ligand systems. Remarkably, larger 1-butene is able to penetrate the dense solid material and to coordinate with copper(I) ions at high molar occupancy. A comparison to analogous ethene and propene complexes of copper(I) is also provided.
(© 2020 Wiley-VCH GmbH.)

Objective To compare the social behaviors of individuals who were tested positive for COVID-19 relative to non-infected individuals.   Methods We sent COVID positive cases and age/gender-matched controls a survey regarding their social behaviors via MyChart (online patient portal). We called cases if they did not complete the electronic survey within two days. Data were collected from May to June 2020. Survey responses for cases without close contact and controls were compared using Pearson chi-square or Fisher's exact tests as appropriate.   Results A total of 339 participants completed the survey (113 cases, 226 controls); 45 (40%) cases had known contact with COVID-19. Cases were more likely to have recently traveled (4% vs. 0%, p = 0.01) or to work outside the home (40% vs. 25%, p = 0.02). There was no difference in the rates of attending private or public gatherings, mask/glove use, hand-washing, cleaning surfaces, and cleaning mail/groceries between cases and controls.   Conclusions Sixty percent of cases had no known contact with COVID-19, indicating ongoing community transmission and underlining the importance of contact tracing. The greater percentage of cases who work outside the home provides further evidence for social distancing and remote telework when possible.
(Copyright © 2021, Speaker et al.)

Gene therapy is highly suited for prostate cancer (PC). Metal-organic-frameworks (MOFs) are potential gene delivery systems. Target-specific cytoplasmic and nuclear knockdown in host gene expression using ZIF-C is shown for the first time through RNAi and CRISPR/Cas9 based gene editing in PC cells. A green tea phytochemical coating enhances intracellular delivery.

Porosity and acidity are influential properties in the rational design of solid-acid catalysts. Probing the physicochemical characteristics of an acidic zeotype framework at the molecular level can provide valuable insights in understanding intrinsic reaction pathways, for affording structure-activity relationships. Herein, we employ a variety of probe-based techniques (including positron annihilation lifetime spectroscopy (PALS), FTIR and solid-state NMR spectroscopy) to demonstrate how a hierarchical design strategy for a faujasitic (FAU) zeotype (synthesized for the first time, via a soft-templating approach, with high phase-purity) can be used to simultaneously modify the porosity and modulate the acidity for an industrially significant catalytic process (Beckmann rearrangement). Detailed characterization of hierarchically porous (HP) SAPO-37 reveals enhanced mass-transport characteristics and moderated acidity, which leads to superior catalytic performance and increased resistance to deactivation by coking, compared to its microporous counterpart, further vindicating the interplay between porosity and moderated acidity.
(© 2020 The Authors. Published by Wiley-VCH GmbH.)

There is a growing interest in using ammonia as a liquid carrier of hydrogen for energy applications. Currently, ammonia is produced industrially by the Haber-Bosch process, which requires high temperature and high pressure. In contrast, bacteria have naturally evolved an enzyme known as nitrogenase, that is capable of producing ammonia and hydrogen at ambient temperature and pressure. Therefore, nitrogenases are attractive as a potentially more efficient means to produce ammonia via harnessing the unique properties of this enzyme. In recent years, exciting progress has been made in bioelectrocatalysis using nitrogenases to produce ammonia. Here, the prospects for developing biological ammonia production are outlined, key advances in bioelectrocatalysis by nitrogenases are highlighted, and possible solutions to the obstacles faced in realising this goal are discussed.
(© 2020 Wiley-VCH GmbH.)

Membranes are crucial to lowering the huge energy costs of chemical separations. Whilst some promising polymers demonstrate excellent transport properties, problems of plasticisation and physical aging due to mobile polymer chains, amongst others, prevent their exploitation in membranes for industrial separations. Here we reveal that molecular interactions between a polymer of intrinsic microporosity (PIM) matrix and a porous aromatic framework additive (PAF-1) can simultaneously address plasticisation and physical aging whilst also increasing gas transport selectivity. Extensive spectroscopic characterisation and control experiments involving two near-identical PIMs, one with methyl groups (PIM-EA(Me2)-TB) and one without (PIM-EA(H2)-TB), directly confirm the key molecular interaction as the adsoprtion of methyl groups from the PIM matrix into the nanopores of the PAF. This interaction reduced physical aging by 50%, suppressed polymer chain mobilities at high pressure and increased H2 selectivity over larger gases such as CH4 and N2.

Ionic liquids and plastic crystals based on pyrrolidinium cations are recognised for their advantageous properties such as high conductivity, low viscosity, and good electrochemical and thermal stability. The pyrrolidinium ring can be substituted with symmetric or asymmetric alkyl chain substituents to form a range of ionic liquids or plastic crystals depending on the anion. However, reports into the use of branched alkyl chains and how this influences the material properties are limited. Here, we report the synthesis of six salts - ionic liquids and organic ionic plastic crystals - where the typically used linear propyl chain substituent is replaced by the branched alternative, isopropyl, to form the cation [C(i3)mpyr]+, in combination with six different anions: dicyanamide, (fluorosulfonyl)(trifluoromethanesulfonyl)imide, bis(trifluoromethanesulfonyl)imide, bis(fluorosulfonyl)imide, tetrafluoroborate and hexafluorophosphate. The thermal and transport properties of these salts are compared to those of the analogous N-propyl-N-methylpyrrolidinium and N,N-diethylpyrrolidinium-based salts. Finally, a high lithium salt content ionic liquid electrolyte based on the bis(fluorosulfonyl)imide salt was developed. This electrolyte showed high coulombic efficiencies of lithium plating/stripping and high lithium ion transference number, making it a strong candidate for use in lithium metal batteries.

Animals, Enzyme Activation genetics, Enzyme Activation immunology, Interleukin-12 genetics, MAP Kinase Signaling System genetics, Macrophages parasitology, Macrophages pathology, Mice, Mice, Knockout, Myeloid Differentiation Factor 88 genetics, Protozoan Proteins genetics, Toxoplasma genetics, Toxoplasmosis genetics, Toxoplasmosis pathology, p38 Mitogen-Activated Protein Kinases genetics, Interleukin-12 immunology, MAP Kinase Signaling System immunology, Macrophages immunology, Myeloid Differentiation Factor 88 immunology, Protozoan Proteins immunology, Toxoplasma immunology, Toxoplasmosis immunology, and p38 Mitogen-Activated Protein Kinases immunology

The apicomplexan Toxoplasma gondii induces strong protective immunity dependent upon recognition by Toll-like receptors (TLR)11 and 12 operating in conjunction with MyD88 in the murine host. However, TLR11 and 12 proteins are not present in humans, inspiring us to investigate MyD88-independent pathways of resistance. Using bicistronic IL-12-YFP reporter mice on MyD88+/+ and MyD88-/- genetic backgrounds, we show that CD11c+MHCII+F4/80- dendritic cells, F4/80+ macrophages, and Ly6G+ neutrophils were the dominant cellular sources of IL-12 in both wild type and MyD88 deficient mice after parasite challenge. Parasite dense granule protein GRA24 induces p38 MAPK activation and subsequent IL-12 production in host macrophages. We show that Toxoplasma triggers an early and late p38 MAPK phosphorylation response in MyD88+/+ and MyD88-/- bone marrow-derived macrophages. Using the uracil auxotrophic Type I T. gondii strain cps1-1, we demonstrate that the late response does not require active parasite proliferation, but strictly depends upon GRA24. By i. p. inoculation with cps1-1 and cps1-1:Δgra24, we identified unique subsets of chemokines and cytokines that were up and downregulated by GRA24. Finally, we demonstrate that cps1-1 triggers a strong host-protective GRA24-dependent Th1 response in the absence of MyD88. Our data identify GRA24 as a major mediator of p38 MAPK activation, IL-12 induction and protective immunity that operates independently of the TLR/MyD88 cascade.

Graphene oxide (GO) is a promising 2D material for adsorbents and membranes, in particular, for the CO 2 separation process. However, CO 2 diffusion and sorption in GO and its layered structures are still not well understood because of its heterogeneous structure. Here we report CO 2 sorption in GO and its derivatives (e.g., reduced GO (rGO)) in powders and films. These CO 2 sorption behaviors reveal that GO is highly CO 2 -philic via complex CO 2 -functional-group-surface interactions, as compared with graphite and rGOs. Even in highly interlocked, lamellar GO films, CO 2 molecules above a certain threshold pressure can diffuse into GO interlayers, causing GO films to swell and leading to dramatic increases in CO 2 sorption. Intercalated water in GO interlayers can be removed by preferential CO 2 sorption without any changes in the GO chemical structure. This finding helps to explain the origin of CO 2 affinity with GO and has implications for preparing anhydrous GO assemblies for various applications.

Polymers with high permeability and strong size-sieving ability are needed for H 2 /CO 2 separation at temperatures ranging from 100 to 300 °C to enable an energy-efficient precombustion CO 2 capture process. However, such polymers usually suffer from a permeability/selectivity tradeoff, that is, polymers with high permeability tend to exhibit a weak size-sieving ability and thus low selectivity. Herein, we demonstrate that carbonization of a suitable polymer precursor (i.e., polybenzimidazole or PBI) generates microcavities (leading to high H 2 permeability) and ultramicroporous channels (leading to strong size-sieving ability and thus high H 2 /CO 2 selectivity). Specifically, carbonization of PBI at 900 °C (CMS@900) doubles H 2 permeability and increases H 2 /CO 2 selectivity from 14 to 80 at 150 °C. When tested with simulated syngas-containing equimolar H 2 and CO 2 in the presence of water vapor for 120 h, CMS@900 exhibits stable H 2 permeability of ≈36 barrer and H 2 /CO 2 selectivity of ≈53 at 150 °C, above Robeson's 2008 upper bound and demonstrating robustness against physical aging and CO 2 plasticization.

Homochiral metal-organic framework (MOF) membranes have been recently reported for chiral separations. However, only a few high-quality homochiral polycrystalline MOF membranes have been fabricated due to the difficulty in crystallization of a chiral MOF layer without defects on porous substrates. Alternatively, mixed matrix membranes (MMMs), which combine potential advantages of MOFs and polymers, have been widely demonstrated for gas separation and water purification. Here we report novel homochiral MOF-polymer MMMs for efficient chiral separation. Homochirality was successfully incorporated into achiral MIL-53-NH 2 nanocrystals by post-synthetic modification with amino acids, such as l-histidine (l-His) and l-glutamic acid (l-Glu). The MIL-53-NH-l-His and MIL-53-NH-l-Glu nanocrystals were then embedded into polyethersulfone (PES) matrix to form homochiral MMMs, which exhibited excellent enantioselectivity for racemic 1-phenylethanol with the highest enantiomeric excess value up to 100 %. This work, as an example, demonstrates the feasibility of fabricating diverse large-scale homochiral MOF-based MMMs for chiral separation.
(© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Plasmids genetics, Transfection methods, Biomimetics methods, DNA chemistry, Genetic Therapy methods, and Zeolites chemistry

Recent work in biomolecule-metal-organic framework (MOF) composites has proven to be an effective strategy for the protection of proteins. However, for other biomacromolecules such as nucleic acids, the encapsulation into nano MOFs and the related characterizations are in their infancy. Herein, encapsulation of a complete gene-set in zeolitic imidazolate framework-8 (ZIF-8) MOFs and cellular expression of the gene delivered by the nano MOF composites are reported. Using a green fluorescent protein (GFP) plasmid (plGFP) as a proof-of-concept genetic macromolecule, successful transfection of mammalian cancer cells with plGFP for up to 4 days is shown. Cell transfection assays and soft X-ray cryo-tomography (cryo-SXT) demonstrate the feasibility of DNA@MOF biocomposites as intracellular gene delivery vehicles. Expression occurs over relatively prolonged time points where the cargo nucleic acid is released gradually in order to maintain sustained expression.
(© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The synthesis and characterisation of new solid-state electrolytes is a key step in advancing the development of safer and more reliable electrochemical energy storage technologies. Organic ionic plastic crystals (OIPCs) are an increasingly promising class of material for application in devices such as lithium or sodium metal batteries as they can support high ionic conductivity, with good electrochemical and thermal stability. However, the choice of OIPC-forming ions is still relatively limited. Furthermore, understanding of the influence of different cations and anions on the thermal, structural and transport properties of these materials is still in its infancy. Here we report the synthesis and in-depth characterisation of a range of new OIPCs utilising the hexamethylguanidinium cation ([HMG]) with five different anions. The thermal, structural, transport properties and free volume in the different salts have been investigated. The free volume within the salts has been investigated by positron annihilation lifetime spectroscopy, and the single crystal and powder X-ray diffraction analysis of [HMG] bis(trifluoromethanesulfonyl)imide ([TFSI]) in phase I and II, [HMG] hexafluorophosphate ([PF 6 ]) and [HMG] tetrafluoroborate ([HMG][BF 4 ]) are reported. The HMG cation can exhibit significant disorder, which is advantageous for plasticity and future use of these materials as high ionic conductivity matrices. The bis(fluorosulfonyl)imide salt, [HMG][FSI], is identified as particularly promising for use as an electrolyte, with good electrochemical stability and soft mechanical properties. The findings introduce a range of new materials to the solid-state electrolyte arena, while the insights into the physico-chemical relationships in these materials will be of importance for the future development and understanding of other ionic electrolytes.