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Heterostructures of two‐dimensional materials realise novel and enhanced physical phenomena, making them attractive research targets. Compared to inorganic materials, coordination nanosheets have virtually infinite combinations, leading to tunability of physical properties and are promising candidates for heterostructure fabrication. Although stacking of coordination materials into vertical heterostructures is widely reported, reports of lateral coordination material heterostructures are few. Here we show the successful fabrication of a seamless lateral heterojunction showing diode behaviour, by sequential and spatially limited immersion of a new metalladithiolene coordination nanosheet, Zn3BHT, into aqueous Cu(II) and Fe(II) solutions. Upon immersion, the Zn centres in insulating Zn3BHT are replaced by Cu or Fe ions, resulting in conductivity. The transmetallation is spatially confined, occurring only within the immersed area. We anticipate that our results will be a starting point towards exploring transmetallation of various two‐dimensional materials to produce lateral heterojunctions, by providing a new and facile synthetic route. [ABSTRACT FROM AUTHOR]

Methyl pyropheophorbides‐a possessing an o/m‐(methoxycarbonyl)phenyl group at the 3‐position were prepared by Diels–Alder reaction of 3‐(trans‐1,3‐butadienyl)chlorin with methyl propiolate and successive didehydrogenation of the resulting 1,4‐cyclohexadienes. The 3‐arylated chlorin bearing the sterically demanding o‐COOMe group as the major product was a 1:1 mixture of high‐performance liquid chromatography‐separable rotational isomers around the C3–C31 bond, while the minor product with the m‐COOMe was less sterically hindered to exhibit rapid atropisomerization at room temperature. The 3‐aryl group of the major product was nearly perpendicular to the chlorin π‐system and less conjugated with the chlorin moiety than that of the minor product wherein more π‐conjugation occurred to give slightly red‐shifted Qy bands. Although both the atropisomers of the o‐substitute in dichloromethane showed similar visible absorption bands and fluorescence emission data, their circular dichroism bands in the ultraviolet‐C light region were dependent on the stereochemistry. [ABSTRACT FROM AUTHOR]

Recent studies on molecular 2D materials with high tunability of structure and function have focused mostly on the discovery of new precursors. Here, we demonstrate a facile one‐pot synthesis of laminated 2D coordination polymer films comprising bis(terpyridine)iron and cobalt at a water/dichloromethane interface. Cross‐sectional elemental mapping unveiled the stratum‐like structure of the film and revealed that the second layer grows to the dichloromethane side below the first layer. Cyclic voltammetry clarified that the bottom layer mediates charge transfer between the top layer and the substrate in a narrow potential region of mixed‐valence states. Furthermore, the bilayer film sandwiched by electrodes in a dry condition shows stable rectification character, and the barrier voltage corresponds to the redox potential difference between the two layers. This study introduces a new strategy for polymer design to explore the materials science of molecular 2D materials. [ABSTRACT FROM AUTHOR]

Organometallic two‐dimensional (2D) nanosheets with tailorable components have recently fascinated the optoelectronic communities due to their solution‐processable nature. However, the poor stability of organic molecules may hinder their practical application in photovoltaic devices. Instead of conventional organometallic 2D nanosheets with low weatherability, an air‐stable π‐conjugated 2D bis(dithiolene)iron(II) (FeBHT) coordination nanosheet (CONASH) is synthesized via bottom‐up liquid/liquid interfacial polymerization using benzenehexathiol (BHT) and iron(II) ammonium sulfate [Fe(NH4)2(SO4)2] as precursors. The uncoordinated thiol groups in FeBHT are easily oxidized, but the Fe(NH4)2(SO4)2 dissociation rate is slow, which facilitates the protection of sulfur groups by iron(II) ions. The density functional theory calculates that the resultant FeBHT network gains the oxygen‐repelling function for oxidation suppression. In air, the FeBHT CONASH exhibits self‐powered photoresponses with short response times (<40 ms) and a spectral responsivity of 6.57 mA W−1, a specific detectivity of 3.13 × 1011 Jones and an external quantum efficiency of 2.23% under 365 nm illumination. Interestingly, the FeBHT self‐powered photodetector reveals extremely high long‐term air stability, maintaining over 94% of its initial photocurrent after aging for 60 days without encapsulation. These results open the prospect of using organometallic 2D materials in commercialized optoelectronic fields. [ABSTRACT FROM AUTHOR]

ORAI1 constitutes the pore‐forming subunit of the calcium release‐activated calcium (CRAC) channel, which is responsible for store‐operated calcium entry into lymphocytes. It is known that ORAI1 is essential for the activation of T cells and mast cells and is considered to be a potent therapeutic target for autoimmune and allergic diseases. Here, we obtained a new humanized antibody, DS‐2741a, that inhibits ORAI1 function. DS‐2741a bound to human‐ORAI1 with high affinity and without cross‐reactivity to rodent Orai1. DS‐2741a demonstrated suppression of CRAC‐mediated human and mouse T‐cell activation and mast cell degranulation in human ORAI1 knock‐in mice. Furthermore, DS‐2741a ameliorated house dust mite antigen‐induced dermatitis in the human ORAI1 knock‐in mouse. Taken together, DS‐2741a inhibited T‐cell and mast cell functions, thus improving skin inflammation in animal models of atopic dermatitis and reinforcing the need for investigation of DS‐2741a for the treatment of allergic diseases in a clinical setting. [ABSTRACT FROM AUTHOR]

In an article published in Angewandte Chemie, Hiroshi Nishihara et al. present a new method for creating lateral heterojunctions in two-dimensional materials. These heterojunctions have rectifying properties and can be fabricated by immersing a coordination nanosheet made from zinc ions and benzenehexathiol into iron and copper salt solutions. This research has implications for utilizing the attractive properties of two-dimensional materials more effectively. The authors of the article include Choon Meng Tan, Naoya Fukui, Kenji Takada, Hiroaki Maeda, Ekaterina Selezneva, Cédric Bourgès, Hiroyasu Masunaga, Sono Sasaki, Kazuhito Tsukagoshi, Takao Mori, Henning Sirringhaus, and Hiroshi Nishihara. [Extracted from the article]

In an article published in Angewandte Chemie International Edition, Hiroshi Nishihara et al. present a new method for creating lateral heterojunctions in two-dimensional materials. These heterojunctions have rectifying properties and are formed by immersing a coordination nanosheet made from zinc ions and benzenehexathiol into iron and copper salt solutions. This research has implications for utilizing the attractive properties of two-dimensional materials more effectively. The authors of the article include Choon Meng Tan, Naoya Fukui, Kenji Takada, Hiroaki Maeda, Ekaterina Selezneva, Cédric Bourgès, Hiroyasu Masunaga, Sono Sasaki, Kazuhito Tsukagoshi, Takao Mori, Henning Sirringhaus, and Hiroshi Nishihara. [Extracted from the article]

New bis(dipyrrinato)zinc(II) complex micro- and nanosheets containing zinc(II) porphyrin ( N2) are synthesized. A liquid/liquid interface method between dipyrrin porphyrin ligand L2 and zinc acetate produces N2 with a large domain size. N2 can be layered quantitatively onto a flat substrate by a modified Langmuir-Schäfer method. N2 deposited on a SnO2 electrode functions as a photoanode for a photoelectric conversion system. The photoresponse of N2 covers the whole visible wavelength range (400-650 nm), with a maximum quantum efficiency of more than twice that of a bis(dipyrrinato)zinc(II) complex nanosheet without porphyrin. [ABSTRACT FROM AUTHOR]

The heterolaminated films show unique redox behavior based on electron transfer mediation, and a stable rectification character owing to the difference in electron transfer kinetics between the two layers. Front Cover: Chemically Laminated 2D Bis(terpyridine)metal Polymer Films: Formation Mechanism at the Liquid-Liquid Interface and Redox Rectification (Chem. Eur. J. 44/2022) Keywords: 2D materials; electron transfer; heterolayers; metal complexes; polymers EN 2D materials electron transfer heterolayers metal complexes polymers 1 1 1 08/08/22 20220804 NES 220804 B Heterolaminated bis(terpyridine)metal films b have been prepared by sequential coordination at the H SB 2 sb O/CH SB 2 sb Cl SB 2 sb interface. [Extracted from the article]

Interfacial electron transfer at bis(tpy)-iron(II) complexes (tpy=2,2′:6′,2′′-terpyridine) on Si(111) electrodes was investigated by using four types of surface-anchor terpyridine ligands. Despite the greater distance, electron transfer between the bis(tpy)-iron(II) unit and the electrode is accelerated in surface-anchor ligands with an additional phenylene group. [ABSTRACT FROM AUTHOR]

This article completes our comprehensive understanding of the electron transport properties of our original π-conjugated redox-active molecular wires comprising Fe bridged by p-phenylene linkers (tpy=2,2′:6′,2′′-terpyridine). The Fe(tpy)2 oligomer wires comprise three types of tpy ligands: the anchor tpy ligand ( A series) makes a junction between the wire and electrode, the bridging bis-tpy ligand ( L series) connects the Fe(tpy)2 units, and the terminal tpy ligand ( T series) possesses a redox site as a probe for the long-range electron transport ability. Taking advantage of the precise tunability of the composition of the Fe(tpy)2 oligomer wires, thus far we investigated how A and L impacted on the electron-transport ability. The excellent long-range electron transport ability with ultrasmall attenuation constants ( βd, 0.002 Å−1 as the minimum) depends on L significantly [ Chem. Asian J. 2009, 4, 1361], whereas A is unrelated to the βd value, but influences the zero-distance electron-transfer rate constant, ket0 [ J. Am. Chem. Soc. 2010, 132, 4524]. Herein we study the influence of terminal ligand T x ( x=1-3). βd is independent of T, however, T3, with a cyclometallated Ru complex as the redox site, gives rise to a ket0 value greater than T1 and T2 with ferrocene. This series of simple but definitive conclusions indicates that we have reached the stage of being able to precisely design molecular wires to attain desirable single-molecule electron conduction. [ABSTRACT FROM AUTHOR]

ABSTRACT Mouse-human chimeric monoclonal antibodies that could neutralize botulinum neurotoxins were developed and an attempt was made to establish mouse hybridoma cell clones that produced monoclonal antibodies that neutralized botulinum neurotoxin serotype A (BoNT/A). Four clones (2-4, 2-5, 9-4 and B1) were selected for chimerization on the basis of their neutralizing activity against BoNT/A and the cDNA of the variable regions of their heavy (VH) and light chains (VL) were fused with the upstream regions of the constant counterparts of human kappa light and gamma 1 heavy chain genes, respectively. CHO-DG44 cells were transfected with these plasmids and mouse-human chimeric antibodies (AC24, AC25, AC94 and ACB1) purified to examine their binding and neutralizing activities. Each chimeric antibody exhibited almost the same capability as each parent mouse mAb to bind and neutralize activities against BoNT/A. From the chimeric antibodies against BoNT/A, shuffling chimeric antibodies designed with replacement of their VH or VL domains were constructed. A shuffling antibody (AC2494) that derived its VH and VL domains from chimeric antibodies AC24 and AC94, respectively, showed much higher neutralizing activity than did other shuffling antibodies and parent counterparts. This result indicates that it is possible to build high-potency neutralizing chimeric antibodies by selecting and shuffling VH and VL domains from a variety of repertoires. A shuffling chimeric antibody might be the best candidate for replacing horse antitoxin for inducing passive immunotherapy against botulism. [ABSTRACT FROM AUTHOR]

π-Conjugated bis(terpyridine)metal (M(tpy)2) oligomer wires were prepared by surface coordination programming such that they displayed an inherent potential gradient along the wire through the chain of metals and bridging ligands. The electron transfer properties of these wires were examined. Heterometal complex wires prepared in the sequence Au(111)-Co(tpy)2-Fe(tpy)2-ferrocene (Fc); that is, Au-[ A azo -1CoL H -1FeT Fc] (( A azo)2 = bis((4-(4′-2,2′;6′,2″-terpyridyl)phenylazo)phenyl)disulfide, L H = bis(terpyridyl)- p-phenylene), displayed a rate constant, ket, for electron transfer at the terminal Fc moiety that was twice that obtained from wires prepared in the sequence electrode-Fe(tpy)2-Co(tpy)2-Fc, Au-[ A azo -1FeL H -1CoT Fc]. This suggested that the oxidation reaction at the terminal Fc moiety was mediated by electron transfer via Co(tpy)2 more efficiently than via Fe(tpy)2. Metal complex wires with an inherent potential gradient based on the heteroligand combination were synthesized using bis(4-(4′-2,2′;6′,2″-terpyridyl) phenyl)disulfide, ( A H)2, or bis(4-(4′-5,5″-difluoro-2,2′;6′,2″-terpyridyl)phenyl)disulfide, ( A F)2, as anchoring ligands and bis(terpyridyl)- p-phenylene, LH, or bis(terpyridyl)-tetrafluoro- p-phenylene, L F, as bridging ligands. Potential step chronoamperometry (PSCA) measurements of the redox reaction of Au-[ A H -1FeL 1 -2FeL F] and Au-[ A F -1FeL F -2FeL H] revealed only small differences in the current-time curves, indicating that the electron self-exchange between the Fe(tpy)2 units in a wire was faster than electron transfer between an electrode surface and the adjacent Fe(tpy)2 units. Fast electron self-exchange suppressed the expected rectification behavior of the wire, despite the presence of a potential staircase within the wire. [ABSTRACT FROM AUTHOR]

It has been reported that the stimulation of neutrophils with N-formyl-Met-Leu-Phe (fMLF), an agonist for formyl peptide receptor (Fpr) 1, renders cells unresponsive to other chemoattractants in vitro. This is known as cross-desensitization, but its functional relevance in neutrophil migration in vivo has not been investigated. Here, we show that precedent stimulation of mouse neutrophils with compound 43, a non-peptidyl agonist for mouse Fpr1 and Fpr2, rendered the cells unresponsive to a second stimulation with C5a, leukotriene B, or keratinocyte-derived cytokine (KC) in calcium mobilization and chemotaxis assays in vitro. The expression of chemokine (C-X-C motif) receptor 2 (CXCR2) on the surface of neutrophils was concomitantly diminished by stimulating the cells with the compound. Moreover, oral administration of the compound to mice before they were exposed to lipopolysaccharide (LPS) aerosol resulted in a dose-dependent reduction in the neutrophil count in bronchoalveolar lavage fluid. The expression of CXCR2 on blood neutrophils was also reduced in the compound-administered mice. The recipient mice that underwent adoptive transfer of fluorescence-labelled neutrophils that had been incubated with the compound showed a substantial decrease in neutrophil counts in bronchoalveolar lavage fluid after they were exposed to LPS, when compared with the control mice to which vehicle-treated neutrophils had been transferred. These results are consistent with the idea that the agonist for Fpr1 and Fpr2 induced cross-desensitization in neutrophils and attenuated neutrophil migration into the airways. Our results also revealed the unpredicted effect of an Fpr1 and Fpr2 dual agonist, which may act as a functional antagonist for multiple chemoattractant receptors in vivo. [ABSTRACT FROM AUTHOR]

Lactobacillus kefiranofaciens was reported to produce an exopolysaccharide named kefiran. In the present study, we developed a new medium, rice hydrolyzate (RH) medium, for the culture of L. kefiranofaciens. Structural analyses revealed that the exopolysaccharide produced by L. kefiranofaciens from RH medium was composed of a hexasaccharide repeating unit, and essentially identical to the kefiran reported in previous studies. A study on the effects of kefiran in animals demonstrated that kefiran significantly suppressed increase of blood pressure and reduced the serum cholesterol levels in SHRSP/Hos rats when subjects consumed excessive dietary cholesterol. Kefiran supplementation demonstrated the ability to significantly lower blood glucose in KKAy mice. In addition, the administration of kefiran in constipated SD rats caused an obvious improvement in the levels of fecal moisture and wet weights of feces. These results suggest that kefiran could be used as a functional food to prevent some commonly occurring diseases. [ABSTRACT FROM AUTHOR]

Self-Powered UV Photodetectors: Two-Dimensional Bis(dithiolene)iron(II) Self-Powered UV Photodetectors with Ultrahigh Air Stability (Adv. Sci. 14/2021) Two-dimensional organic-inorganic materials have been unable to break the bottleneck of photocurrent generation without external bias due to their poor electrical properties. Moreover, the selfpowered photodetectors maintained 94% of their initial photocurrent after 60 days of aging in air without encapsulation. [Extracted from the article]

NKCP is the completely refined protein layer from cultured Bacillus subtilis (natto) and is supplied in tablet form. It lacks the distinctive fermented odor and bacteria associated with fresh natto. Almost all vitamin K is removed during the manufacturing process. The main component of NKCP is the active fragment of Bacillopeptidase F, which is a serine protease secreted by Bacillus subtilis. In in vivo studies, NKCP shows fibrinolytic and amidolytic activity on plasmin specific synthetic substrate. Daily oral administration of NKCP in 28 volunteers for two weeks and then in 23 volunteers for several months, was examined. The fibrinolytic effect was demonstrated by a shortened euglobulin lysis time in both trials. Furthermore, we observed an improvement in shoulder stiffness. These results suggest that the oral administration of NKCP can be expected to have a fibrinolytic effect and cause positive changes in local blood flow. Further investigations may demonstrate NKCP to be useful in the prevention of thrombosis. [ABSTRACT FROM AUTHOR]

The preventive effect of Hydrolyzed Rice Bran against the common cold syndrome was examined in elderly people. Arabinoxylan derivatives of Hydrolyzed Rice Bran (HRB) were prepared from water-soluble rice bran through partial processing using a carbohydrate complex. Using the water-soluble Rice Bran (RB) as a control, a cross over double-blind study was conducted on both substances over a 6-week administration period. Fifty elderly people aged from 70 to 95 years participated in the study and the comparative data from 36 participants were analyzed. There were no withdrawals from in the study due to the side effects of the experimental foods. Symptoms were observed and scored. The total symptom score for the RB treatment group was three times higher than that for the HRB treatment group. The average duration of symptoms was 2.6 days for RB whereas it was only 1.2 days for HRB. Furthermore, some immunomodulatory action was observed in laboratory tests. HRB was shown to be useful in reducing the physical stress associated with acute respiratory tract infection. [ABSTRACT FROM AUTHOR]

Information on an article "Coordination Programming of Two-Dimensional Metal Complex Frameworks" by H. Maeda and others, published in the periodical "Langmuir" in 2016 is presented.