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1.
Chem Commun (Camb) ; 58(25): 4056-4059, 2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35262118

RESUMO

The detection of X-rays has always been a frontier of scientific research. An Eu-MOF with both X-ray-induced photochromic and scintillation properties has been synthesized through the combination of a photochromism-active viologen ligand and rare earth Eu element with high-efficiency absorption of X-rays. In a bright environment, Eu-MOF exhibits different color changes under high-energy X-rays and low-energy X-rays, which can effectively distinguish X-rays. Eu-MOF can also be used for X-ray detection by scintillation properties in dark environments. This work provides a new perspective on the design of multifunctional materials that can perform simple X-ray detection in different environments.

2.
Zhongguo Zhong Yao Za Zhi ; 46(15): 4016-4022, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34472279

RESUMO

The tumor prescriptions contained in Dictionary of Tumor Formulas, Compendium of Good Tumor Formulas, Chinese Pharmacopoeia, Ministry of Health Drug Standards for Chinese Medicine Formulas and National Compilation of Standards for Proprietary Chinese Medicines were selected and organized to construct a database for tumor prescriptions, and the data mining techniques were applied to investigate the prescription regularity of colorectal cancer prescriptions. The formula data were extracted after screening in strict accordance with the inclusion and exclusion criteria, and were then analyzed with Microsoft Excel 2010 for frequency statistics, Apriori block provided by SPSS Clementine 12.0 software for correlation rule analysis, and arules and arulesViz packages in R 4.0.2 software for correlation rule visualization. In addition, SPSS 18.0 software was used for cluster analysis and factor analysis, in which cluster analysis was performed by Ochiai algorithm with bicategorical variables in systematic clustering method and factor analysis was performed mainly with principal component analysis. A total of 285 prescriptions were included in the statistical analysis, and the frequency statistics showed that 43 herbs had been used more than 16 times. The association rules analysis showed that 26 high-frequency me-dicine pair rules were obtained, and the association rules for those dispelling evil spirits, strengthening the body, resolving stasis, dispelling dampness, etc. were visualized. In the cluster analysis, we generated a dendrogram from which 7 groups of traditional Chinese medicines with homogeneity were extracted. 10 common factors were obtained in the factor analysis. The types of herbal medicines involved in the colorectal cancer prescription included anti-cancer antidotes, strengthening and tonifying medicines, blood-regulating medicines, and expectorant medicines, corresponding to the treatment for eliminating evil spirits, strengthening, resolving stasis, and expectorating dampness. The prescriptions for anti-cancer detoxification were normally based on the pairs composed of Scutellaria barbata-Hedyotis diffusa and Sophora flavescens, Sargentodoxa cuneata, S. barbata, often combined with stasis relieving drug and dampness eliminating drug, reflecting the characteristics of treatment for both toxicity and stasis, dampness and toxicity simultaneously. The prescriptions for strengthening the righteousness and tonifying the deficiency were composed of Astragalus membranaceus and Atractylodes macrocephala mainly, exerting the effect of benefiting Qi, strengthening the spleen and drying dampness, tonifying kidney and essence, tonifying blood and invigorating blood. Meanwhile, anti-cancer detoxification medicines shall be reduced as much as possible. The compatibility of the medicines for the intestinal tract reflected the principle of using the right medicine for the right condition and eliminating evil spirits or strengthening the body, as appropriate.


Assuntos
Neoplasias Colorretais , Medicamentos de Ervas Chinesas , Neoplasias Colorretais/tratamento farmacológico , Mineração de Dados , Prescrições de Medicamentos , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Medicina Tradicional Chinesa
3.
Inorg Chem ; 60(13): 9278-9281, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34142822

RESUMO

A high contrast of ∼67 times, exceeding those of all known photoswitching bulk quadratic nonlinear-optical materials, has been realized in a photochromic semiconductor, by the strategy of increasing electron-transfer efficiency and self-absorption.

4.
Stem Cell Res Ther ; 12(1): 257, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933157

RESUMO

BACKGROUND: Cutaneous wound healing and regeneration have become a recognized health challenge in the world, which causes severe damage to the mental and physical health of patients. Human adipose-derived mesenchymal stem cells (hADSC) play an essential role in wound healing via their paracrine function. Exosomes secreted by hADSC may contribute to this progress. In this study, we investigated the potential clinical application roles of hADSC and hADSC-derived exosomes (hADSC-Exo) in cutaneous wound healing. METHODS: hADSC-Exo was isolated from human hADSC by ultracentrifugation. Mice were subjected to a full-thickness skin biopsy experiment and treated with either control vehicle or hADSC or hADSC-Exo by smearing administration (sm) or subcutaneous administration (sc) or intravenous administration (iv). The efficacy of hADSC and hADSC-Exo on wound healing was evaluated by measuring wound closure rates, histological analysis. RESULTS: Combined application of local hADSC-Exo smearing and hADSC/hADSC-Exo intravenous administration offered the additional benefit of promoting wound healing, accelerating re-epithelialization, reducing scar widths, and enhancing angiogenesis and collagen synthesis. Either topical application of hADSC-Exo or systemic administration with hADSC/hADSC-Exo appeared more effective in stimulating cell proliferation, inhibiting cell apoptosis and inflammation, and promoting skin elasticity and barrier integrity, with increased genes expression of PCNA, VEGF, collagen III, Filaggrin, Loricrin, and AQP3, with decreased genes expression of TNF-alpha. CONCLUSION: Our findings suggest that the combined administration of hADSC/hADSC-Exo can facilitate cutaneous wound healing and reduce scar formation. These data provide the first evidence for the feasibility of smearing of hADSC-Exo as a cell-free therapy in treating cutaneous wounds, and the potential clinical value of combined administration of hADSC/hADSC-Exo.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Animais , Proliferação de Células , Humanos , Camundongos , Pele , Cicatrização
5.
Inorg Chem ; 60(2): 560-564, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33411521

RESUMO

Photochromic open-framework compounds are of potential application in detection/sensors. The issue of improving the detection limits has received much attention. We synthesized a new open-framework Zn compound, namely, compound 1 ([Zn(MQ)(IPA)Cl]·5H2O) (MQ = N-methyl-4,4'-bipyridinium, IPA = m-phthalic acid), which showed a 1D channel structure by a cationic-π interaction. It is noteworthy that this compound is an effective detector for aniline though luminescence emission, which exhibited unprecedented detection limits in photochromic open-framework compounds.

6.
Chem Commun (Camb) ; 56(93): 14689-14692, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33165482

RESUMO

Utilization of photochromism in photo-switchable white-light emitters (WLEs) is a challenging task. In an effort to achieve this, we have recently developed a new Gd-MOF using a photoactive pyridinium-based inner salt. The compound shows interesting photoswitchable bluish white light to greenish yellow light emission as a result of electron transfer, a phenomenon that has not been observed previously in photochromic crystal compounds.

7.
Dalton Trans ; 49(22): 7309-7314, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32458956

RESUMO

The synergy of unusual X-aggregation induced luminescent chromophores and heavy Pb(ii) ions has facilitated excellent X-ray scintillation of two structurally similar Pb-SMOFs, which are heat-resistant due to solvent-free lattices. Owing to their higher Pb(ii) contents, Pb-SMOFs with larger X-ray absorption coefficients are more sensitive for X-ray dosage detection than powdered CsPbBr3.

8.
Chem Commun (Camb) ; 54(87): 12349-12352, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30324190

RESUMO

A radiochromic material with energy-dependent X-ray-induced photochromism was obtained by incorporating a radiosensitive glycolate ligand into an electron-transfer photochromic metalloviologen system. It is highly promising for detecting soft X-rays with energies less than 2 keV and may find application in qualitatively and visually distinguishing the energy range of X-rays.

9.
Chemistry ; 23(31): 7414-7417, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28425125

RESUMO

N,N'-Disubstituted bipyridinium (viologen) and N-monosubstituted bipyridinium compounds are well known for their electron-transfer (ET) photochromic behavior. Their modification has exclusively focused on the N-substituents to date. For the first time, we have studied the photochromic behavior when one pyridyl ring of the bipyridinium is substituted with a multifunctional azole group, and have found that two new coordination compounds based on N-methyl-4-pyridinium tetrazolate (mptz) zwitterion, [Zn(mptz)2 Br2 ] (1) and [Cd3 (mptz)2 Cl6 ]n ⋅4n H2 O (2), exhibit typical ET photochromic behavior owing to photoinduced ET from halogen anion to the mptz ligand. This work demonstrates a new simple, neutral photoactive molecule with electron-accepting ability, which may act as a photoactive component for materials with potential photoswitching and photocatalysis applications.

10.
Microcirculation ; 24(3)2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28129474

RESUMO

The disruption of endothelial integrity and the occurrence of angiogenesis in response to AGEs contribute greatly to micro- and macrovascular complications associated with DM. Among human dermal, brain, and retinal vascular ECs, activation of ERM, moesin, by phosphorylation of Thr-558 is involved in AGE-induced hyperpermeability and angiogenesis via the Rho and ROCK (Rho/ROCK) and p38 pathways. Src also plays an important role in AGE-induced endothelial barrier dysfunction by phosphorylating moesin, VE-cadherin, and FAK. Furthermore, recent studies have demonstrated that ROS serve as a key mediator of the AGE-induced endothelial response. ROS inhibition would greatly benefit ECs. This review focuses on the role of moesin in microvascular permeability and angiogenesis, and on the involvement of Src and ROS in endothelial barrier disruption.


Assuntos
Endotélio Vascular/fisiopatologia , Produtos Finais de Glicação Avançada/fisiologia , Proteínas dos Microfilamentos/fisiologia , Permeabilidade Capilar , Humanos , Neovascularização Patológica , Espécies Reativas de Oxigênio/metabolismo , Quinases da Família src/metabolismo
11.
Chem Sci ; 8(11): 7751-7757, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30210760

RESUMO

Nonlinear optical (NLO) switchable materials are important for photonic and optoelectronic technologies. One important issue for NLO photoswitching, the most studied physical switching approach, is how to improve the switching contrast of second harmonic generation (SHG) in crystals, because the known values are generally below 3 times. Thermoswitching, as another approach, has shown impressive high SHG-switching contrasts (4-∞ times), but the fast decay of thermally induced states demands constant heat sources to maintain specific SHG intensities. We have synthesized a photochromic and thermochromic bistable acentric compound, ß-[(MQ)ZnCl3] (MQ+ = N-methyl-4,4'-bipyridinium), which represents the first crystalline compound with both photo- and heat-induced SHG-switching behavior and the first example of a thermoswitchable NLO crystal that can maintain its expected second-order NLO intensity without any heat source. The SHG-switching contrast can reach about 8 times after laser irradiation or 2 times after thermal annealing. The former value is the highest recorded for photoswitchable NLO crystals. This work also indicates that higher SHG-switching contrasts may be obtained through increasing electron-transfer efficiency, variation of permanent dipole moment, and self-absorption.

12.
Angew Chem Int Ed Engl ; 56(2): 554-558, 2017 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-27918125

RESUMO

Electron-transfer (redox) thermochromism was successfully used for switching the conductance of semiconductors, by introducing a thermally active organic component into an inorganic semiconducting framework. A moisture-resistant semiconductor {(MV)2 [Pb7 Br18 ]}n (MV2+ =methyl viologen cation) has been prepared through an in situ synthetic method for MV2+ . It features a rare 3D haloplumbate open framework and unprecedented electron-transfer thermochromic behavior in haloplumbates. The electrical conductivity of this compound dropped significantly after coloration and restored after decoloration, which was satisfactorily explained by valence band XPS and theoretical data. This work not only offers a new approach to modify electrical properties of semiconductors without altering components or structures, but may lead to the development of over-temperature color indicators, circuit overload protectors or photovoltaic materials.

13.
Chem Commun (Camb) ; 52(51): 7947-9, 2016 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-27257638

RESUMO

With the help of theoretical predictions, we have found, from the [donor-metal-acceptor] system, the first photochromic pyrazine-based compound that can undergo photoinduced charge separation and yield stable pyrazine radicals.

14.
J Am Chem Soc ; 137(34): 10882-5, 2015 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-26284651

RESUMO

Polycyanometallate compounds with both photochromism and photomagnetism have appealing applications in optical switches and memories, but such optical behaviors were essentially restricted to the cryogenic temperature. We realized, for the first time, the photochromism and photomagnetism of 3d-4f hexacyanoferrates at room temperature (RT) in [Eu(III)(18C6)(H2O)3]Fe(III)(CN)6·2H2O (18C6 = 18-crown-6). Photoinduced electron transfer (PET) from crown to Fe(III) yields long-lived charge-separated species at RT in air in the solid state and also weakens the magnetic susceptibility significantly. The PET mechanism and changing trend of photomagnetism differ significantly from those reported for known 3d-4f hexacyanoferrates. This work not only develops a new type of inorganic-organic hybrid photochromic material but opens a new avenue for RT photomagnetic polycyanometallate compounds.

15.
Angew Chem Int Ed Engl ; 53(43): 11529-31, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25195919

RESUMO

The first bulk electron-transfer photochromic compound with intrinsic second-order nonlinear optical (NLO) photoswitching properties has been synthesized. This system employs an electron-transfer photoactive asymmetric viologen ligand coordinated to a zinc(II) center.

16.
Inorg Chem ; 53(11): 5538-45, 2014 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-24845065

RESUMO

Two new member of (V)((2n+2)/2)[Bi(2n)Cl(8n+2)] series hybrids, (BzV)2[Bi2Cl10] (1) and (BzV)5[Bi3Cl14]2·(C6H5CH2)2O (2) (where BzV(2+) = N,N'-dibenzyl-4,4'-bipyridinium and (C6H5CH2)2O = dibenzyl ether) have been obtained, and compound 2 contains an unprecedented discrete trimer [Bi3Cl14](5-) counterion. The novel in situ-synthesized symmetric viologen cation with aromatic groups on both sides of 4,4'-bipy would provide more opportunities to create π···π interactions to optimize the photochromic property of the hybrid, and different bismuthated-halide oligomers enable us to discuss the size effect in this series of compounds. Both 1 and 2 are photochromic, and their photoresponsive rate is faster than that of reported viologen-metal halide hybrids. Experimental and theoretical data illustrated that the size of the inorganic oligomer can significantly influence the photoresponsive rate of the viologen dication, and the π···π interaction behaves as not only a powerful factor to stabilize the viologen monocation radical but also the second electron-transfer pathway, from a π-conjugated substituent to a viologen cation, for the photochromic process.


Assuntos
Benzil Viologênio/química , Bismuto , Cloretos , Elétrons , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Morfolinos , Compostos Organometálicos/química , Processos Fotoquímicos
17.
Inorg Chem ; 53(2): 847-51, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24359084

RESUMO

The model compound [Zn(HCOO)2(4,4'-bipy)] (1; 4,4'-bipy = 4,4'-bipyridine) is selected in this work to demonstrate the effectiveness of our previously proposed design strategy for electron-transfer photochromic metal-organic complexes. The electron-transfer photochromic behavior of 1 has been discovered for the first time. Experimental and theoretical data illustrate that the photochromism of 1 can be attributed to the electron transfer from formato to 4,4'-bipy and the formation of a radical photoproduct. The electron transfer prefers to occur between formato and 4,4'-bipy, which are combined directly by the Zn(II) atoms. A high-contrast (up to 8.3 times) photoluminescence switch occurs during the photochromic process. The similarity of photochromic behaviors among 1 and its analogues as well as viologen compounds has also been found. Photochromic studies of this model compound indicate that new electron-transfer photochromic metal-organic complexes can be largely designed and synthesized by the rational assembly of nonphotochromic electron-donating and electron-accepting ligands.

18.
Inorg Chem ; 52(3): 1199-205, 2013 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-23323956

RESUMO

A series of inorganic-organic hybrid compounds L(2)(Bi(2)Cl(10)) (L = HMV(2+) = N-proton-N'-methyl-4,4'-bipyridinium for 1, L = HBzV(2+) = N-proton-N'-benzyl-4,4'-bipyridinium for 2, and L = HPeV(2+) = N-proton-N'-phenethyl-4,4'-bipyridinium for 3) have been successfully synthesized by an in situ solvothermal reaction. Compounds 1-3, with the same metal halide as anions but different asymmetric viologen molecules as cations, are ideal model compounds for investigating the detailed effect of different photochromically active molecules on the photochromic properties of the hybrids. Compound 1 shows no photochromic behavior, but compounds 2 and 3 possess photochromism and show a faster photoresponse rate than other reported viologen metal halide hybrids. Studies on the relationship between the structure and photochromic behavior clearly reveal that π-conjugated substituents could be used to improve the photoresponsibility and enrich the developed color efficiently and that the π···π interaction among organic components may not only be a powerful factor to stabilize the viologen monocation radical but also act as the second path of electron transfer from the π-conjugated substituent to the viologen cation for the photochromic process, which significantly influences the photochromic properties.


Assuntos
Bismuto/química , Elétrons , Compostos Organometálicos/química , Viologênios/química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Processos Fotoquímicos
19.
Dalton Trans ; 41(31): 9532-42, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22760421

RESUMO

Four new lead(II) or bismuth(III) selenites and a tellurite, namely, Pb(3)(TeO(3))Cl(4), Pb(3)(SeO(3))(2)Br(2), Pb(2)Cd(3)(SeO(3))(4)I(2)(H(2)O), Pb(2)Ge(SeO(3))(4) and BiFe(SeO(3))(3), have been prepared and structurally characterized by single crystal X-ray diffraction (XRD) analyses. These compounds exhibit five different types of structures. The structure of Pb(3)(TeO(3))Cl(4) features a three-dimensional (3D) lead(II) chloride network with tellurite anions filling in the 1D tunnels of Pb(4) 4-member rings (MRs) along the c-axis. Pb(3)(SeO(3))(2)Br(2) contains a 3D network composed of lead(II) selenite layers interconnected by bromide anions. Pb(2)Cd(3)(SeO(3))(4)I(2)(H(2)O) is a 3D structure based on 2D cadmium(II) selenite layers which are further connected by 1D lead(II) iodide ladder chains with lattice water molecules located at the 1D tunnels of the structure. Pb(2)Ge(SeO(3))(4) features a 3D framework constructed by the alternate arrangement of lead(II) selenite layers and germanium(iv) selenite layers in the [100] direction. The structure of BiFe(SeO(3))(3) is built on the 3D anionic framework of ion(III) selenite with the bismuth(III) ions located at its Fe(6)Se(6) 12-MR tunnels. Pb(3)(TeO(3))Cl(4) (Pna2(1)) is polar and BiFe(SeO(3))(3) (P2(1)2(1)2(1)) is noncentrosymmetric. Powder second-harmonic generation (SHG) measurements using 1064 nm radiation indicate that BiFe(SeO(3))(3) exhibits a weak SHG efficiency of about 0.2 × KH(2)PO(4) (KDP). Magnetic property measurements for BiFe(SeO(3))(3) show a dominant antiferromagnetic interaction with weak spin-canting at low temperatures. IR, UV-vis and thermogravimetric, as well as electronic structure calculations were also performed.

20.
Chem Commun (Camb) ; 48(48): 5989-91, 2012 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-22576457

RESUMO

This work presents a prototype of chiral porous metal-organic framework with the porous wall decorated by different functional groups. The special structure in conjunction with the gas adsorption results reveals some relationship between CO2 adsorption and functional points. Moreover, outstanding tunable photoluminescence and direct white-light emission is observed.

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