• Mohammad Kassem, Maria Bokova, Andrey S. Tverjanovich, Daniele Fontanari, David Le Coq, Anton Sokolov, Pascal Masselin, Shinji Kohara, Takeshi Usuki, Alex C. Hannon, Chris J. Benmore and Eugene Bychkov*, Bent HgI2 Molecules in the Melt and Sulfide Glasses: Implications for Nonlinear Optics, Chem. Mater. 2019. DOI: 10.1021/acs.chemmater.9b00860

    Nonlinear optical (NLO) crystals are widely used in advanced photonic technologies for second harmonic and difference frequency generation (SHG and DFG, respectively), producing coherent light at frequencies where existing lasers are unavailable. Isotropic glasses do not exhibit SHG or DFG, except temporarily induced anisotropy under external stimuli. However, recent reports on glasses with chiral structural motifs show promising permanent NLO properties. We propose an alternative solution: hybrid molecular/network glasses with noncentrosymmetric HgI2 monomers. Mercury(II) iodide consists of linear HgI2 triatomic molecules in the vapor phase and in the yellow orthorhombic polymorph stable above 400 K. At lower temperatures, the tetragonal red form is composed of corner-sharing HgI4/2 tetrahedra forming a layered extended framework...

  • Dan Wang, Lihui Xiao, Peixia Yang,* Zhengrui Xu, Xiangyu Lu, Lei Du,* Oleg Levin, Liping Ge, Xiaona Pan, Jinqiu Zhang and Maozhong An, Dual-nitrogen-source engineered Fe–Nx moieties as a booster for oxygen electroreduction, J. Mater. Chem. A, 2019, 7, 11007-11015. DOI: 10.1039/C9TA01953G

    Metal–air batteries, particularly Zn–air batteries, have triggered considerable enthusiasm of communities due to their high theoretical power density. Developing highly active, cost-effective and alternative non-precious metal catalysts for the oxygen reduction reaction (ORR) is pivotal for popularizing zinc–air batteries. The rational design and synthesis of this type of catalyst are therefore critical, but it is still challenging to control the well-defined active sites as expected. Herein, we report a dual-nitrogen-source mediated route for synergistically controlling the formation of active Fe–Nx moieties that are embedded in the carbon matrix...

  • Maartje J.Levels, Cynthia M.Fehres, Lisa G.M. van Baarsen, Nathalie O.P. van Uden, Kristine Germar, Tom G.O'Toole, Iris C.J.Blijdorp, Johanna F.Semmelink, Marieke E.Doorenspleet, Arjen Q.Bakker, Mikhail Krasavin, Alexey Tomilin, Sophie Brouard, Hergen Spits, Dominique L.P.Baeten, Nataliya G.Yeremenko, BOB.1 controls memory B-cell fate in the germinal center reaction, J. Autoimmun. 2019. DOI: 10.1016/j.jaut.2019.04.011

    During T cell-dependent (TD) germinal center (GC) responses, naïve B cells are instructed to differentiate towards GC B cells (GCBC), high-affinity long-lived plasma cells (LLPC) or memory B cells (Bmem). Alterations in the B cell-fate choice could contribute to immune dysregulation leading to the loss of self-tolerance and the initiation of autoimmune disease. Here we show that mRNA levels of the transcription regulator BOB.1 are increased in the lymph node compartment of patients with rheumatoid arthritis (RA), a prototypical autoimmune disease caused by the loss of immunological tolerance. Investigating to what extent levels of BOB.1 impact B cells during TD immune responses we found that BOB.1 has a crucial role in determining the B cell-fate decision. High BOB.1 levels promote the generation of cells with phenotypic and functional characteristics of Bmem. Mechanistically, overexpression of BOB.1 drives ABF1 and suppresses BCL6, favouring Bmem over LLPC or recycling GCBC. Low levels of BOB.1 are sufficient for LLPC but not for Bmem differentiation...

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Репрезентативные публикации за апрель 2019 г.

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Maxim Shevtsov, Stefan Stangl, Boris Nikolaev, Ludmila Yakovleva, Yaroslav Marchenko, Ruslana Tagaeva, Wolfgang Sievert, Emil Pitkin, Anton Mazur, Peter Tolstoy, Oleg Galibin, Vyacheslav Ryzhov, Katja Steiger, Oleg Smirnov, William Khachatryan, Kerry Chester, Gabriele Multhoff, Granzyme B Functionalized Nanoparticles Targeting Membrane Hsp70‐Positive Tumors for Multimodal Cancer Theranostics, Small, V. 15, P. 1900205, 2019. DOI: 10.1002/smll.201900205

Abstract

Functionalized superparamagnetic iron oxide nanoparticles (SPIONs) have emerged as potential clinical tools for cancer theranostics. Membrane‐bound 70 kDa heat shock protein (mHsp70) is ubiquitously expressed on the cell membrane of various tumor types but not normal cells and therefore provides a tumor‐specific target. The serine protease granzyme B (GrB) that is produced as an effector molecule by activated T and NK cells has been shown to specifically target mHsp70 on tumor cells. Following binding to Hsp70, GrB is rapidly internalized into tumor cells. Herein, it is demonstrated that GrB functionalized SPIONs act as a contrast enhancement agent for magnetic resonance imaging and induce specific tumor cell apoptosis. Combinatorial regimens employing stereotactic radiotherapy and/or magnetic targeting are found to further enhance the therapeutic efficacy of GrB‐SPIONs in different tumor mouse models.


Muhammad Abdullah Butt, Antonino Calà Lesina, Martin Neugebauer, Thomas Bauer, Lora Ramunno, Alessandro Vaccari, Pierre Berini, Yuriy Petrov, Denis Danilov, Alina Manshina, Peter Banzer, Gerd Leuchs, Investigating the Optical Properties of a Laser Induced 3D Self‐Assembled Carbon–Metal Hybrid Structure, Small, 2019, V.15, 1900512. DOI: 10.1002/smll.201900512

Abstract

Carbon‐based and carbon–metal hybrid materials hold great potential for applications in optics and electronics. Here, a novel material made of carbon and gold–silver nanoparticles is discussed, fabricated using a laser‐induced self‐assembly process. This self‐assembled metamaterial manifests itself in the form of cuboids with lateral dimensions on the order of several micrometers and a height of tens to hundreds of nanometers. The carbon atoms are arranged following an orthorhombic unit cell, with alloy nanoparticles intercalated in the crystalline carbon matrix. The optical properties of this metamaterial are analyzed experimentally using a microscopic Müller matrix measurement approach and reveal a high linear birefringence across the visible spectral range. Theoretical modeling based on local‐field theory applied to the carbon matrix links the birefringence to the orthorhombic unit cell, while finite‐difference time‐domain simulations of the metamaterial relates the observed optical response to the distribution of the alloy nanoparticles and the optical density of the carbon matrix.


T.V.Plisko, A.V.Penkova, K.S.Burts, A.V.Bildyukevich, M.E.Dmitrenko, G.B.Melnikova, R.R.Atta, A.S.Mazur, A.A.Zolotarev, A.B.Missyul, Effect of Pluronic F127 on porous and dense membrane structure formation via non-solvent induced and evaporation induced phase separation, Journal of Membrane Science, V. 580, Pages 336-349. DOI: 10.1016/j.memsci.2019.03.028

Abstract

Novel porous and dense membranes based on polysulfone (PSF) modified by poly(ethylene glycol)–b–poly(propylene glycol)–b– poly(ethylene glycol) (Pluronic F127) were developed. The influence of Pluronic F127 introduction to the casting solution on different types of polymer membrane formation via two different phase inversion techniques—non-solvent induced phase separation (NIPS) for porous membranes and evaporation induced phase separation (EIPS) for dense membranes—was investigated. According to the triangular phase diagram obtained, PSF-Pluronic F127-N,N-dimethylacetamide (DMAc) systems feature lower critical solution temperature and have a tendency to micelle formation due to Pluronic F127 self-assembly. The structure, hydrophilic-hydrophobic balance and physicochemical properties of PSF-Pluronic F127 membranes were characterized by water contact angle measurements, scanning electron microscopy, nuclear magnetic resonance, small-angle X-ray scattering, and atomic force microscopy. The performance of dense membranes in pervaporation separation of water-ethyl acetate mixtures was investigated to reveal the effect of Pluronic F127 on the structure and free volume of the PSF-Pluronic F127 membranes. It was shown that Pluronic F127 introduction to the casting solution during membrane formation via two different techniques (NIPS and EIPS) leads to the increase in the pore size of the porous membranes and free volume of the dense membranes, as well as the increase in flux and surface hydrophilicity for both membrane types. Pluronic F127 was found to improve the antifouling performance of porous PSF-Pluronic F127 membranes in the BSA solution ultrafiltration. The introduction of 3 wt% Pluronic F127 into dense PSF membrane improved permeation flux in 1.7 and 2.7 times (15.1 and 27.3 g/(m2h)) at high selectivity level (100 wt% water in the permeate) during the separation of ethyl acetate-water mixtures (2 and 4 wt% ethyl acetate) compared to pristine PSF membrane.

Ответственный за содержание сайта Института химии: Роман Зумберов, r.zumberov@spbu.ru