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Pyrene boxes, self‐assembled from 1,3,5,8‐pyrene‐tetrasulfonate anions, PTS4− and Guanidinium G+, amino‐guanidinium AG+ and hydrated alkali counter cations have been used for the encapsulation of 1,ω‐amino‐acids of variable lengths. The NMR spectroscopy illustrates that these systems are stable in aqueous solution and encapsulation process involves dynamic or fixed guest molecules within Pyrene box, depending of the nature of the counter‐cations. The amide bond coupling between the amino‐guanidinium AG+ and encapsulated 1,ω‐amino‐acid guests occur in water in the absence of coupling catalysts. The variable co‐encapsulation of the guests via multivalent stabilizing interactions shed light that chemical selection can be obtained from mixtures of 1,ω‐amino‐acids. Our study involving a comprehensive screening of 18 co‐crystal structures help to understand the in‐situ fixation of 1,ω‐amino‐acid guests and their accurate determination of unconventional structures under confinement. [ABSTRACT FROM AUTHOR]

Owing to their significant physiological functions, especially as selective relays for translocation of physiological relevant species through cellular membranes, natural ion channels play important role in the living organisms. During the last decades, the field of self‐assembled ion channels has been continuously developed. Convergent multidimensional self‐assembly strategies have been used for the synthesis of unimolecular channels or non‐covalent self‐organized channels, designed to mimic natural ion channel proteins and for which a rich array of interconverting or adaptive channel conductance states can be observed. In this review, we give an overview on the development of various self‐assembled artificial channels in a bottom‐up approach, especially their design, self‐assembly behaviour, transport activity in lipid bilayer membranes, mechanism of transport and comparison with natural ion channels. Finally, we discuss their applications, the potential challenges facing in this field as well as future development and perspectives. [ABSTRACT FROM AUTHOR]

Aufgrund ihrer wichtigen physiologischen Funktionen, insbesondere als selektive Relais für die Translokation physiologisch relevanter Spezies durch Zellmembranen, spielen natürliche Ionenkanäle eine wichtige Rolle in lebenden Organismen. In den letzten Jahrzehnten hat sich das Gebiet der selbstorganisierten Ionenkanäle kontinuierlich weiterentwickelt. Für die Synthese unimolekularer Kanäle oder nichtkovalent selbstorganisierter Kanäle, die zum Nachahmen natürlicher Ionenkanalproteine ausgelegt sind und für die vielfältige, sich ineinander umwandelnde oder adaptive Kanalleitungszustände beobachtet werden können, wurden konvergente mehrdimensionale Selbstorganisationsstrategien verwendet. In diesem Aufsatz geben wir eine Übersicht über die Entwicklung verschiedener selbstorganisierter künstlicher Kanäle, insbesondere ihren Aufbau, das Selbstorganisationsverhalten, die Transportaktivität in Lipiddoppelschichtmembranen, Transportmechanismen, und stellen Vergleiche mit natürlichen Ionenkanälen an. Wir diskutieren die Anwendungen künstlicher Ionenkanäle sowie mögliche Probleme, die das Gebiet erwarten, und zukünftige Entwicklungen. [ABSTRACT FROM AUTHOR]

Transmembrane protein channels are an important inspiration for the design of artificial ion channels. Their dipolar structure helps overcome the high energy barrier to selectively translocate water and ions sharing one pathway, across the cell membrane. Herein, we report that the amino‐imidazole (Imu) amphiphiles self‐assemble via multiple H‐bonding to form stable artificial Cl−‐channels within lipid bilayers. The alignment of water/Cl− wires influences the conduction of ions, envisioned to diffuse along the hydrophilic pathways; at acidic pH, Cl−/H+ symport conducts along a partly protonated channel, while at basic pH, higher Cl−/OH− antiport translocate through a neutral channel configuration, which can be greatly activated by applying strong electric field. This voltage/pH regulated channel system represents an unexplored alternative for ion‐pumping along artificial ion‐channels, parallel to that of biology. [ABSTRACT FROM AUTHOR]

A 3D porous perchlorinated metal-organic framework (MOF), LIFM-26, featuring dual functionality, that is, functional polar groups and open metal sites, has been synthesized using perchlorinated linear dicarboxylate to link trigonal prismatic Fe3(μ3-O) units. LIFM-26 exhibits good thermal and chemical stability, and possesses high porosity with a BET surface area of 1513 m2 g−1, compared with isoreticular MOF-235 and Fe3O(F4BDC)3(H2O)3 (F4BDC=2,3,5,6-tetrafluorobenzene-1,4-dicarboxylate). Most strikingly, LIFM-26 features good gas sorption/separation performance at 298 K and 1 atm with IAST selectivity values reaching up to 36, 93, 23, 11, 46, and 202 for CO2/CH4, CO2/N2, C2H4/CH4, C2H6/CH4, C3H8/CH4, and R22/N2 (R22=CHClF2), respectively, showing potential for use in biogas/natural gas purification and CO2/R22 capture. [ABSTRACT FROM AUTHOR]

Transmembrane protein channels are an important inspiration for the design of artificial ion channels. Their dipolar structure helps overcome the high energy barrier to selectively translocate water and ions sharing one pathway, across the cell membrane. Herein, we report that the amino-imidazole (Imu) amphiphiles self-assemble via multiple H-bonding to form stable artificial Cl - -channels within lipid bilayers. The alignment of water/Cl - wires influences the conduction of ions, envisioned to diffuse along the hydrophilic pathways; at acidic pH, Cl - /H + symport conducts along a partly protonated channel, while at basic pH, higher Cl - /OH - antiport translocate through a neutral channel configuration, which can be greatly activated by applying strong electric field. This voltage/pH regulated channel system represents an unexplored alternative for ion-pumping along artificial ion-channels, parallel to that of biology., (© 2020 Wiley-VCH GmbH.)

Although the photodimerization of acenaphthylene (ACE) has been known for 100 years, the asymmetric cycloaddition of its 1-substituted derivatives is unknown. Herein, we report a supramolecular photochirogenic approach in which a homochiral and photoactive Δ/Λ-[Pd 6 (RuL 3 ) 8 ] 28+ metal-organic cage (Δ/Λ-MOC-16) is used as a supramolecular reactor for the enantioselective exited-state photocatalysis of 1-Br-ACE. Owing to preorganization of the substrates by the supramolecular cage, stereochemical control of the triplet state, and nanospace transfer of energy and chirality, the cycloaddition of ACE proceeded with high selectivity for the formation of anti over syn stereoisomers, whereas the regio-, stereo-, and enantioselective cycloaddition of unsymmetrical 1-Br-ACE showed effective enantiodifferentiation of a pair of anti head-to-head stereoisomers. The enzyme-mimicking photocatalysis was verified by catalytic turnover, rate enhancement, and competing-guest inhibition experiments., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A 3D porous perchlorinated metal-organic framework (MOF), LIFM-26, featuring dual functionality, that is, functional polar groups and open metal sites, has been synthesized using perchlorinated linear dicarboxylate to link trigonal prismatic Fe 3 (μ 3 -O) units. LIFM-26 exhibits good thermal and chemical stability, and possesses high porosity with a BET surface area of 1513 m 2  g -1 , compared with isoreticular MOF-235 and Fe 3 O(F 4 BDC) 3 (H 2 O) 3 (F 4 BDC=2,3,5,6-tetrafluorobenzene-1,4-dicarboxylate). Most strikingly, LIFM-26 features good gas sorption/separation performance at 298 K and 1 atm with IAST selectivity values reaching up to 36, 93, 23, 11, 46, and 202 for CO 2 /CH 4 , CO 2 /N 2 , C 2 H 4 /CH 4 , C 2 H 6 /CH 4 , C 3 H 8 /CH 4 , and R22/N 2 (R22=CHClF 2 ), respectively, showing potential for use in biogas/natural gas purification and CO 2 /R22 capture., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Aim: To establish a new model for predicting survival in acute-on-chronic liver failure (ACLF) patients treated with an artificial liver support system., Methods: One hundred and eighty-one ACLF patients who were admitted to the hospital from January 1, 2012 to December 31, 2014 and were treated with an artificial liver support system were enrolled in this retrospective study, including a derivation cohort (n = 113) and a validation cohort (n = 68). Laboratory parameters at baseline were analyzed and correlated with clinical outcome. In addition to standard medical therapy, ACLF patients underwent plasma exchange (PE) or plasma bilirubin adsorption (PBA) combined with plasma exchange. For the derivation cohort, Kaplan-Meier methods were used to estimate survival curves, and Cox regression was used in survival analysis to generate a prognostic model. The performance of the new model was tested in the validation cohort using a receiver-operator curve., Results: The mean overall survival for the derivation cohort was 441 d (95%CI: 379-504 d), and the 90- and 270-d survival probabilities were 70.3% and 58.3%, respectively. The mean survival times of patients treated with PBA plus PE and patients treated with PE were 531 d (95%CI: 455-605 d) and 343 d (95%CI: 254-432 d), respectively, which were significantly different (P = 0.012). When variables with bivariate significance were selected for inclusion into the multivariate Cox regression model, number of complications, age, scores of the model for end-stage liver disease (MELD) and type of artificial liver support system were defined as independent risk factors for survival in ACLF patients. This new prognostic model could accurately discriminate the outcome of patients with different scores in this cohort (P < 0.001). The model also had the ability to assign a predicted survival probability for individual patients. In the validation cohort, the new model remained better than the MELD., Conclusion: A novel model was constructed to predict prognosis and accurately discriminate survival in ACLF patients treated with an artificial liver support system.

Aim: To evaluate whether the combination of recombinant chicken fibroblast growth factor receptor-1 (FGFR-1) protein vaccine (cFR-1) combined with low-dose gemcitabine would improve anti-tumor efficacy in a mouse CT26 colon adenocarcinoma (CT26) model., Methods: The CT26 model was established in BABL/c mice. Seven days after tumor cell injection, mice were randomly divided into four groups: combination therapy, cFR-1 alone, gemcitabine alone, and normal saline groups. Tumor growth, survival rate of tumor-bearing mice, and systemic toxicity were observed. The presence of anti-tumor auto-antibodies was detected by Western blot analysis and enzyme-linked immunospot assay, microvessel density (MVD) of the tumors and tumor cell proliferation were detected by Immunohistochemistry staining, and tumor cell apoptosis was detected by TdT-mediated biotinylated-dUTP nick end label staining., Results: The combination therapy results in apparent decreases in tumor volume, microvessel density and tumor cell proliferation, and an increase in apoptosis without obvious side-effects as compared with either therapy alone or normal control groups. Also, both auto-antibodies and the antibody-producing B cells against mouse FGFR-1 were detected in mice immunized with cFR-1 vaccine alone or with combination therapy, but not in non-immunized mice. In addition, the deposition of auto-antibodies on endothelial cells from mice immunized with cFR-1 was observed by immunofluorescent stain-ing, but not on endothelial cells from control groups. Synergistic indexes of tumor volume, MVD, cell apoptosis and proliferation in the combination therapy group were 1.71 vs 1.15 vs 1.11 and 1.04, respectively, 31 d after tumor cell injection., Conclusion: The combination of cFR-1-mediated anti-angiogenesis and low-dose gemcitabine synergistically enhances the anti-tumor activity without overt toxicity in mice.