Anisotropy is an intrinsic property of crystalline materials. However, the photoluminescence anisotropy in eutectic crystals of organometallic complexes has remained unexplored. Herein, the eutectic ...of polynuclear lanthanide complexes and Ag clusters was prepared, and the crystal shows significant photoluminescence anisotropy. The polarization anisotropy of emission δ and degree of excitation polarization P are 2.62 and 0.53, respectively. The rare excitation polarization properties have been proved to be related to the regular arrangement of electric transition dipole moments of luminescent molecules in the crystal. Our design provides a reference for developing new photoluminescence anisotropy materials and expanding their applications.
The eutectic of Ag clusters and polynuclear lanthanide complexes induces fluorescence anisotropy. Investigation of the excitation polarization mechanism confirmed that the electrons in the ground state have higher transition efficiency when the direction of the electric field vibration of the photon and the direction of the molecular electric transition dipole moment are parallel.
Bimetallic catalysts have recently emerged as promising candidates for CO2 reduction. However, it is still critical to strategically synthesize atomically precise bimetallic catalysts and clarify the ...interaction mechanism of bimetal sites. Herein, we connected the active metallic porphyrin and phthalocyanine moieties by the unique benzimidazole linkage to obtain a novel Ni,Co-based bimetallic covalent organic framework (denoted as NiPc-CoPor-imi-COF), for efficient electrocatalytic CO2 conversion. Compared with its monometallic Ni and Co counterparts, NiPc-CoPor-imi-COF with a synergistic effect exhibited much higher activity and selectivity with a maximum CO faradaic efficiency (FECO) of 97.1%. Mechanistic studies revealed that the efficient charge transport along the COF backbone promoted electronic communication between the bimetallic active sites and enabled regulation of the intrinsic activity of each catalytic center, namely improving the activity of Ni sites by promoting *COOH generation and optimizing the selectivity of Co sites by depressing *H formation, thus ultimately achieving high CO2 conversion efficiency. This work provides insights into synergistic catalysis with bimetallic sites for efficient CO2 reduction.
Elaborately designed stimuli-responsive antibacterial systems are highly desirable for infected diabetic wound treatment. Herein, hierarchically porous metal-organic framework (MOF)-based ...glucose-responsive microneedles (MNs) were designed for painless transdermal wound treatment. For the first time, a hierarchically porous MOF was applied for consuming the surplus glucose to protect infected diabetic wounds from bacterial infection. Through one-pot synthesis, glucose oxidase (GOx) was firstly encapsulated into a Fe-doped zeolitic imidazolate framework (ZIF), and based on a properly controlled tannic acid (TA) etching process, the hierarchically porous MOF (GOx@Fe-ZIF-TA) was constructed afterwards. GOx encapsulated in GOx@Fe-ZIF-TA could consume surplus glucose in infected diabetic wounds to yield gluconic acid and H
2
O
2
. The latter could be catalyzed by Fe(
ii
) to generate antibacterial &z.rad;OH, which would not result in antimicrobial resistance. The as-obtained hierarchically porous MOF revealed satisfactory glucose-responsive antibacterial activity, and the hierarchically porous MOF-based MNs showed enough stiffness for penetration. This study offers a new strategy, using hierarchically porous enzyme-loaded MOFs as depots to integrate with MNs, for designing stimuli-responsive transdermal systems for the treatment of infected diabetic wounds and other diseases.
In this work, hierarchically porous metal-organic framework (MOF)-based microneedles were designed for glucose-responsive infected diabetic wound treatment.
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•Fe(III)-MOFs were synthesized by microwave-assisted ball approach.•Fe(III)-MOFs were successfully used for removal of organic dyes in aqueous solutions.•The removal of organic dyes ...process was carried out under natural light.
Fe-based metal-organic frameworks(Fe(III)-MOFs)were synthesized by Fe2(SO4)3 and trimesic acid using microwave-assisted ball milling method. The structure of the Fe(III)-MOFs was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectrometry (FTIR). The thermostability of the MOFs was analyzed by thermogravimetric analysis (TGA). Fe(III)-MOFs were added in aqueous solutions to remove organic dyes. The removal efficiencies of Orange II, CR and MB reached 95.9%, 98.7%, 95.7% respectively at 10℃ and reached 97.7%, 99.7%, 97.5% respectively at 35℃ in 300 min.
“Qi deficiency and blood stasis” syndrome is one of the most common syndromes treated with Traditional Chinese Medicine among ischemic heart disease (IHD) patients in clinic. As a Chinese herbal ...formula with the function of tonifying Qi and activating blood, Yiqihuoxue Decoction (YQHX) has been frequently proven to be effective in the clinical treatment of IHD.
The cardioprotective mechanisms of YQHX in treating ischemic heart disease were investigated, with emphasis on the key targets and pathways.
In the present study, the potential targets of compounds identified in YQHX were predicted using PharmMapper, Symmap, and STITCH databases, and a “herb-compound-target” network was constructed using Cytoscape. Subsequently, the GO and KEGG functional enrichment analyses were analyzed using the DAVID database. Furthermore, a protein-protein interaction network was constructed using STRING to obtain the key target information. Besides, we used a myocardial ischemia rat model to investigate the cardioprotective effects of YQHX. Transmission electron microscopy and Western blotting were used to observe apoptotic bodies and confirm protein expressions of key candidate targets, respectively.
Network pharmacology showed that a total of 141 potential targets were obtained from these databases. The functional analysis results revealed that the targets of YQHX were largely associated with apoptosis, and the PI3K-AKT and MAPK pathways might represent key functional pathways. The hub genes of network include ALB, TP53, AKT1, TNF, VEGFA, EGFR, MAPK1, CASP3, JUN, FN1, MMP9, and MAPK8. In vivo, YQHX significantly improved cardiac function and suppressed apoptosis in ischemic rat myocardium. Furthermore, YQHX could significantly upregulate Nrf2 and HO-1 expression, and inhibit JNK phosphorylation.
Based on network pharmacology and experimental evidence, this study proves that the cardioprotective effects and mechanisms of YQHX depend on multi-component, multi-target, and multi-pathway. In particular, YQHX exerts anti-apoptotic effects potentially by regulating the Nrf2/HO-1 and JNK-MAPK pathways.
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Anisotropy is an intrinsic property of crystalline materials. However, the photoluminescence anisotropy in eutectic crystals of organometallic complexes has remained unexplored. Herein, the eutectic ...of polynuclear lanthanide complexes and Ag clusters was prepared, and the crystal shows significant photoluminescence anisotropy. The polarization anisotropy of emission δ and degree of excitation polarization P are 2.62 and 0.53, respectively. The rare excitation polarization properties have been proved to be related to the regular arrangement of electric transition dipole moments of luminescent molecules in the crystal. Our design provides a reference for developing new photoluminescence anisotropy materials and expanding their applications.
The eutectic of Ag clusters and polynuclear lanthanide complexes induces fluorescence anisotropy. Investigation of the excitation polarization mechanism confirmed that the electrons in the ground state have higher transition efficiency when the direction of the electric field vibration of the photon and the direction of the molecular electric transition dipole moment are parallel.
In order to understand the effect of mechanical stretch on corneal extracellular matrix remodeling, human keratoconus fibroblasts (HKCFBs) were subjected to cyclic stretch in vitro and the expression ...of matrix metalloproteinases (MMPs), tissue inhibitor of metalloproteinases (TIMPs), and inflammatory cytokines were evaluated. HKCFBs were seeded into a flexible membrane base and subjected to a cyclic stretch regimen of 10% equibiaxial stretch at a stretching frequency of 1 Hz for 6 h using a Flexcell tension unit. An antibody directed against interleukin‑6 (IL‑6 Ab) was used to investigate the roles of IL‑6 on mechanical stretch mediated regulation of MMP in HKCFBs. Culture supernatants were assayed using an enzyme‑linked immunosorbent assay for MMP‑1 and ‑3, TIMP‑1 and ‑2, and IL‑6. Total RNA from the cells was extracted, and quantitative polymerase chain reaction was used to determine mRNA for MMP‑1 and ‑3, TIMP‑1 and ‑2, and IL‑6. In stretched cells, levels of MMP‑1 and ‑3 demonstrated an increase compared with unstretched cells, but levels of TIMP‑1, and ‑2 revealed a decrease. Mechanical stretch significantly increased the mRNA expression and protein synthesis of IL‑6 compared with unstretched cells. IL‑6 induced MMP‑1 and ‑3 expression, whereas no significant effects were observed in levels of TIMP‑1 and ‑2 compared with the untreated control groups. Additionally, the IL‑6 Ab markedly inhibited the stretch‑induced increase in MMP‑1 and ‑3 in culture supernatants in a dose‑dependent manner. No significant differences in TIMP‑1 and ‑2 protein levels were detected between stretched cells treated with IL‑6 Ab and stretched cells without IL‑6 Ab treatment. These results indicate that cyclical mechanical stretch augments IL‑6 production and MMP expression, and reduces levels of TIMP in HKCFBs. Thus, it is suggested that IL‑6 mediates the stretch‑induced MMP expression.
This paper proposes a novel Through wall imaging（TWI） algorithm combined with phase compensation and Nonuniform fast Fourier transform（NUFFT）.The wall effect is cancelled with phase ...compensation,which is implemented by multiplying the conjugated wall transmissivity with the received echoes.The NUFFT technique is implemented to calculate the imaging results.The proposed method has two merits：The phase compensation avoids a time-consuming calculation of the incidences angles;the image is reconstructed more accurately and efficiently than the conventional Interpolation-fast Fourier transform（IPFFT） method.The new method is implemented on 2D synthetic-generated data and experimental data.The results demonstrate that our method generates high quality focused images and achieves target geometrical identification within a very short time.
This paper proposes a novel Through wall imaging(TWI) algorithm combined with phase compensation and Nonuniform fast Fourier transform(NUFFT).The wall effect is cancelled with phase ...compensation,which is implemented by multiplying the conjugated wall transmissivity with the received echoes.The NUFFT technique is implemented to calculate the imaging results.The proposed method has two merits:The phase compensation avoids a time-consuming calculation of the incidences angles;the image is reconstructed more accurately and efficiently than the conventional Interpolation-fast Fourier transform(IPFFT) method.The new method is implemented on 2D synthetic-generated data and experimental data.The results demonstrate that our method generates high quality focused images and achieves target geometrical identification within a very short time.
Bimetallic catalysts have recently emerged as promising candidates for CO 2 reduction. However, it is still critical to strategically synthesize atomically precise bimetallic catalysts and clarify ...the interaction mechanism of bimetal sites. Herein, we connected the active metallic porphyrin and phthalocyanine moieties by the unique benzimidazole linkage to obtain a novel Ni,Co-based bimetallic covalent organic framework (denoted as NiPc-CoPor-imi-COF), for efficient electrocatalytic CO 2 conversion. Compared with its monometallic Ni and Co counterparts, NiPc-CoPor-imi-COF with a synergistic effect exhibited much higher activity and selectivity with a maximum CO faradaic efficiency (FE CO ) of 97.1%. Mechanistic studies revealed that the efficient charge transport along the COF backbone promoted electronic communication between the bimetallic active sites and enabled regulation of the intrinsic activity of each catalytic center, namely improving the activity of Ni sites by promoting *COOH generation and optimizing the selectivity of Co sites by depressing *H formation, thus ultimately achieving high CO 2 conversion efficiency. This work provides insights into synergistic catalysis with bimetallic sites for efficient CO 2 reduction.
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