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1.
J Org Chem ; 88(20): 14836-14841, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37779438

RESUMEN

A series of diphenylboron-chelating N-substituent 8-aminoquinoline, 5-aminoquinoxaline, and 1-aminophenazine were prepared. They exhibit lowest energy absorption peaks of 444-766 nm, emission peaks of 563-820 nm, and quantum yields of up to 46.5%. Electrochemical and theoretical studies indicate that the N-substituent mainly determines the HOMO and the framework determines the LUMO, thus allowing for a wide-tuning of absorptions/emissions. Intramolecular charge transfer transition leads to large Stokes shifts of up to 166 nm. One selected compound showed satisfactory cytocompatibility and cytoplasm-targeting cell imaging ability.

2.
Biosens Bioelectron ; 238: 115564, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37544105

RESUMEN

The identification and detection of mesenchymal circulating tumor cells (mCTCs) is important for early warning of tumor metastasis. The majority of conventional detection methods for CTCs rely on the recognition of epithelial biomarkers, which is technically challenging for detecting CTCs with epithelial-mesenchymal transition (EMT)-induced phenotypic alteration. In this work, we have constructed a label-free biosensor for sensitive electrochemical assay of mCTCs. In our design, the capture probe can recognize the vimentin overexpressed on the surface of mCTCs with high specificity. Meantime, the network-like DNA nanoprobes with multiple G-quadruplex/hemin complexes and multiple cholesterol molecules can be grafted to the cell surface based on the high affinity between cholesterol molecules and cell membrane. Owing to the mimic horseradish peroxidase of G-quadruplex/hemin complexes, strong electrochemical responses will be obtained for sensitive quantification of mCTCs with a detection limit of 8 cell mL-1. Moreover, the biosensor can effectively overcome the interference of vimentin negative cells or secretory vimentin, and realize the recovery tests in whole blood with high accuracy, thereby may further promoting the diagnosis and personalized treatment of cancer in clinic.


Asunto(s)
Técnicas Biosensibles , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patología , Vimentina/metabolismo , Hemina , Biomarcadores de Tumor , ADN , Transición Epitelial-Mesenquimal/genética
3.
Biomolecules ; 12(1)2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-35053229

RESUMEN

Photodynamic therapy (PDT) is a treatment modality that uses light to target tumors and minimize damage to normal tissues. It offers advantages including high spatiotemporal selectivity, low side effects, and maximal preservation of tissue functions. However, the PDT efficiency is severely impeded by the hypoxic feature of tumors. Moreover, hypoxia may promote tumor metastasis and tumor resistance to multiple therapies. Therefore, addressing tumor hypoxia to improve PDT efficacy has been the focus of antitumor treatment, and research on this theme is continuously emerging. In this review, we summarize state-of-the-art advances in strategies for overcoming hypoxia in tumor PDTs, categorizing them into oxygen-independent phototherapy, oxygen-economizing PDT, and oxygen-supplementing PDT. Moreover, we highlight strategies possessing intriguing advantages such as exceedingly high PDT efficiency and high novelty, analyze the strengths and shortcomings of different methods, and envision the opportunities and challenges for future research.


Asunto(s)
Neoplasias/tratamiento farmacológico , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Hipoxia Tumoral , Humanos , Neoplasias/metabolismo
4.
China Pharmacy ; (12): 848-852, 2022.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-923192

RESUMEN

OBJECTIVE To prepare cinnamaldehyde (CA) loaded liposomes bilayer-modified by bovine serum albumin (BSA)/chitosan (CTS)(BSA/CTS-Lip-CA) in order to improve the sustained-release effect and storage stability of the nanoparticles. METHODS Firstly,cinnamaldehyde loaded liposomes (Lip-CA)and blank liposomes (Lip-Blank)were prepared by thin film dispersion method. Then chitosan modified cinnamaldehyde loaded liposome (CTS-Lip-CA)and BSA/CTS-Lip-CA were obtained by electrostatic adsorption. Finally , the prepared liposomes were characterized , and their in vitro release characteristics and storage stability were investigated. RESULTS The particle size of BSA/CTS-Lip-CA was (177.8±4.0)nm and the Zeta potential was (-15.6±1.5)mV;they were in spherical shape ;FTIR analysis showed that the modification of BSA and CTS had no effect on the internal structure of liposomes. The results of in vitro drug release characteristics showed that the cumulative release of Lip-CA ,CTS-Lip-CA and BSA/CTS-Lip-CA within 10 hours were 82.9%,74.1% and 72.9% respectively. The results of storage stability showed that after 30 days of storage ,the particle sizes of Lip-CA ,CTS-Lip-CA and BSA/ CTS-Lip-CA were (134.2±2.1),(151.7±0.4),(164.8±1.5)nm;the retention rates of model drug CA were 65.4%,82.5% and 90.2% respectively. CONCLUSIONS BSA/CTS-Lip-CA is successfully prepared. It has a certain sustained-release effect and can improve the storage stability of the drug to a certain extent.

5.
Inorg Chem ; 55(15): 7295-300, 2016 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-27408952

RESUMEN

Organic metalloporphyrins and inorganic polyoxometalates (POMs) are two kinds of efficient molecular catalysts to prompt a variety of chemical reactions. They have been used as active moieties for the synthesis of porous materials to realize highly efficient heterogeneous catalysis. Both of them are regarded as the organic/inorganic equivalent counterparts to complement the individual features. Therefore, the combination of metalloporphyrins and POMs in the same hybrid materials might generate interesting catalytic properties by emerging their unique individual functions. To avoid the random connections between metalloporphyrins, POMs, and lanthanide connecting nodes, we have developed a "step-by-step" aggregation strategy, including the reaction of POMs with metal ions to bind metal nodes on the surfaces of POMs at the first step and the reaction of the resulting POM derivatives with metalloporphyrin linkers to result in hybrid materials at the second step. Catalytic experiments demonstrate that the resulting hybrid material exhibits interesting catalytic properties in the heterogeneous epoxidation of olefins, in which the conversion, epoxide selectivity, turnover number, and turnover frequency for the epoxidation of styrene to (1,2-epoxyethyl)benzene are >99%, 94%, 220000, and 22000 h(-1), respectively. These results demonstrate that the collaborative work of multiple active sites in hybrid materials can achieve superior high efficiency in heterogeneous catalysis.

6.
Chempluschem ; 81(8): 758-763, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31968835

RESUMEN

The probing of volatile organic compounds (VOCs) is critical and challenging in biotechnology and environmental monitoring. Incorporation of luminescent moieties into metal-organic frameworks (MOFs) has produced many unique luminescent sensors for probing different VOCs. The emissions of most MOF sensors are based mainly on the single transitions of luminescent moieties, so the luminescence readouts are only predominant for some special VOCs. We use a natural amino acid derivative as the luminescent moiety to result in a lamellar coordination polymer, and further embed luminescent dye molecules in the crystal matrix to result in a luminescent dye@MOF sensor. The composite sensor exhibits excellent sensitivity for decoding different VOCs with clearly differentiable fluorescence emission by tuning the energy transfer efficiency from the organic ligand to the dye moieties. The composite luminescent sensor is self-calibrated, and much more stable and instantaneous than other more widely explored luminescent sensors.

8.
Dalton Trans ; 44(17): 7862-9, 2015 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-25820348

RESUMEN

Zwitterions and polyoxometalates (POMs) are two kinds of functional moieties with very different properties for applications in different fields. We have developed an effective strategy to successfully immobilize these two different moieties into the frameworks of porous hybrid materials, in which the POM units act as templates and photoactive moieties. These hybrid materials demonstrate remarkable efficiency for selective scavenging and photolysis of cationic dyes from polluted water, and up to 10% dye uptake and quantitative photolysis of dyes have been realized.

9.
Dalton Trans ; 44(5): 2038-41, 2015 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-25515613

RESUMEN

A novel 3D porous metal-organic framework was constructed from imidazole carboxylate linkers and copper(ii) nodes, which in situ generates multiple active Cu(II) sites in the nanosized channel walls for highly efficient cross dehydrogenative coupling reaction between 1,2,3,4-tetrahydroisoquinoline derivatives and nitroalkanes that are superior to the simple copper salts.

10.
Chinese Journal of Cancer ; (12): 325-334, 2015.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-349588

RESUMEN

Ribosome-inactivating proteins (RIPs) belong to a family of enzymes that attack eukaryotic ribosomes and potently inhibit cellular protein synthesis. RIPs possess several biomedical properties, including anti-viral and anti-tumor activities. Multiple RIPs are known to inhibit tumor cell proliferation through inducing apoptosis in a variety of cancers, such as breast cancer, leukemia/lymphoma, and hepatoma. This review focuses on the anti-tumor activities of RIPs and their apoptotic effects through three closely related pathways: mitochondrial, death receptor, and endoplasmic reticulum pathways.


Asunto(s)
Animales , Humanos , Antineoplásicos , Apoptosis , Retículo Endoplásmico , Mitocondrias , Proteínas de Plantas , Receptores de Muerte Celular , Proteínas Inactivadoras de Ribosomas , Ribosomas
11.
Anal Chem ; 86(13): 6648-53, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24892790

RESUMEN

A flexible tripodal polyaromatic acid (4,4',4″-(((2,4,6-trimethylbenzene-1,3,5-triyl)-tris(methylene))-tris(oxy))tribenzoic acid, H3TCM) was used to adapt the coordination sites of lanthanide ions for the construction of microporous lanthanide-organic frameworks (LOFs) [LnTCM(H2O)2]·3DMF·H2O (Ln-TCM; Ln = La, Eu, and/or Tb). In these LOFs, the emission band of TCM matches well with the excitation energy of lanthanide ions (Eu(3+) and Tb(3+)) which results in high-efficient resonance energy transfer from TCM to lanthanide ions. Moreover, the mixed EuxTb1-x-TCM has tunable pores to adapt different induced-fit-type host-guest interactions which can modulate both the energy transfer efficiency from TCM to Ln(3+) ions and the energy allocation between Eu(3+) and Tb(3+) ions in the luminescence spectra. We demonstrate that the Eu(x)Tb(1-x)-TCM sensor has the capability of decoding different volatile organic molecules (VOMs) with a clearly differentiable and unique emission intensity ratio of (5)D0 → (7)F2 (Eu(3+), 614 nm) to (5)D4 → (7)F5 (Tb(3+), 545 nm) transitions for every different VOM. Compared with the traditional absolute emission intensity method, such a self-referencing emission intensity strategy has generated self-calibrating, highly differentiable, and very stable luminescent signals for decoding different VOMs from the unique Eu(x)Tb(1-x)-TCM platform, which has great potential for practical applications.


Asunto(s)
Elementos de la Serie de los Lantanoides/química , Sustancias Luminiscentes/química , Compuestos Organometálicos/química , Compuestos Orgánicos Volátiles/análisis , Mediciones Luminiscentes/métodos , Modelos Moleculares
12.
Acc Chem Res ; 47(4): 1199-207, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24499017

RESUMEN

Metalloporphyrins are the active sites in monooxygenases that oxidize a variety of substrates efficiently and under mild conditions. Researchers have developed artificial metalloporphyrins, but these structures have had limited catalytic applications. Homogeneous artificial metalloporphyrins can undergo catalytic deactivation via suicidal self-oxidation, which lowers their catalytic activity and sustainability relative to their counterparts in Nature. Heme molecules in protein scaffolds can maintain high efficiency over numerous catalytic cycles. Therefore, we wondered if immobilizing metalloporphyrin moieties within porous metal-organic frameworks (MOFs) could stabilize these structures and facilitate the molecular recognition of substrates and produce highly efficient biomimetic catalysis. In this Account, we describe our research to develop multifunctional porphyrinic frameworks as highly efficient heterogeneous biomimetic catalysts. Our studies indicate that porous porphyrinic frameworks provide an excellent platform for mimicking the activity of biocatalysts and developing new heterogeneous catalysts that effect new chemical transformations under mild conditions. The porous structures and framework topologies of the porphyrinic frameworks depend on the configurations, coordination donors, and porphyrin metal ions of the metalloporphyrin moieties. To improve the activity of porous porphyrinic frameworks, we have developed a two-step synthesis that introduces the functional polyoxometalates (POMs) into POM-porphyrin hybrid materials. To tune the pore structures and the catalytic properties of porphyrinic frameworks, we have designed metalloporphyrin M-H8OCPP ligands with four m-benzenedicarboxylate moieties, and introduced the secondary auxiliary ligands. The porphyrin metal ions and the secondary functional moieties that are incorporated into porous metal-organic frameworks greatly influence the catalytic properties and activities of porphyrinic frameworks in different reactions, such as the oxidation of alkylbenzenes, olefins, and hexane and the photo-oxygenation of 1,5-dihydroxynaphthalene and sulfides. The porphyrin metal ions and the secondary auxiliary sites in the pores can work together synergistically to enhance the catalytic activities of porphyrinic frameworks. Compared with their homogeneous counterparts, the activities and stabilities of the heterogeneous porphyrinic frameworks are remarkable: the immobilization of metalloporphyrins onto the pore surfaces of MOFs not only prevents their suicidal self-oxidation but also allows them to activate inert substrate molecules, such as cyclohexane. Moreover, because the bulky molecules cannot easily access the active sites inside the pores of porphyrinic frameworks, these porous materials demonstrate interesting size-selective catalytic properties toward substrates.


Asunto(s)
Metaloporfirinas/química , Biomimética , Catálisis , Dominio Catalítico , Técnicas de Química Sintética , Hierro/química , Ácidos de Lewis/química , Manganeso , Metaloporfirinas/síntesis química , Compuestos Organometálicos/química , Oxidación-Reducción , Porosidad , Estireno/química , Propiedades de Superficie
13.
Angew Chem Int Ed Engl ; 53(6): 1575-9, 2014 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-24382789

RESUMEN

Self-assembly of luminescent moieties into porous metal-organic frameworks (MOFs) has generated many luminescent platforms for probing volatile organic molecules (VOMs). However, most of those explored thus far have only been based on the luminescence intensity of one transition, which is not efficient for probing different VOMs. We have synthesized a luminescent MOF material containing 1D nanotube channels, and further developed a luminescent dye@MOF platform to realize the probing of different VOMs by tuning the energy transfer efficiency between two different emissions. The dye@MOF platform exhibits excellent fingerprint correlation between the VOM and the emission peak-height ratio of ligand to dye moieties. The dye@MOF sensor is self-calibrating, stable, and instantaneous, thus the approach should be a very promising strategy to develop luminescent materials with unprecedented practical applications.

14.
Chemistry ; 19(44): 14886-94, 2013 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-24115143

RESUMEN

Two new organic building units that contain dicarboxylate sites for their self-assembly with paddlewheel [Cu2(CO2)4] units have been successfully developed to construct two isoreticular porous metal-organic frameworks (MOFs), ZJU-35 and ZJU-36, which have the same tbo topologies (Reticular Chemistry Structure Resource (RCSR) symbol) as HKUST-1. Because the organic linkers in ZJU-35 and ZJU-36 are systematically enlarged, the pores in these two new porous MOFs vary from 10.8 Šin HKUST-1 to 14.4 Šin ZJU-35 and 16.5 Šin ZJU-36, thus leading to their higher porosities with Brunauer-Emmett-Teller (BET) surface areas of 2899 and 4014 m(2) g(-1) for ZJU-35 and ZJU-36, respectively. High-pressure gas-sorption isotherms indicate that both ZJU-35 and ZJU-36 can take up large amounts of CH4 and CO2, and are among the few porous MOFs with the highest volumetric storage of CH4 under 60 bar and CO2 under 30 bar at room temperature. Their potential for high-pressure swing adsorption (PSA) hydrogen purification was also preliminarily examined and compared with several reported MOFs, thus indicating the potential of ZJU-35 and ZJU-36 for this important application. Studies show that most of the highly porous MOFs that can volumetrically take up the greatest amount of CH4 under 60 bar and CO2 under 30 bar at room temperature are those self-assembled from organic tetra- and hexacarboxylates that contain m-benzenedicarboxylate units with the [Cu2(CO2)4] units, because this series of MOFs can have balanced porosities, suitable pores, and framework densities to optimize their volumetric gas storage. The realization of the two new organic building units for their construction of highly porous MOFs through their self-assembly with [Cu2(CO2)4] units has provided great promise for the exploration of a large number of new tetra- and hexacarboxylate organic linkers based on these new organic building units in which different aromatic backbones can be readily incorporated into the frameworks to tune their porosities, pore structures, and framework densities, thus targeting some even better performing MOFs for very high gas storage and efficient gas separation under high pressure and at room temperature in the near future.

15.
J Am Chem Soc ; 134(48): 19851-7, 2012 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-23163641

RESUMEN

A metal-organic nanotube (MONT) was synthesized by linking up the bent organic ligands and the tetra-coordinated zinc cations under mild conditions. Structural analysis revealed that the MONT has a very large exterior wall diameter of 4.91 nm and an interior channel diameter of 3.32 nm. Interlocking of the nanotubes gives rise to a 3D chiral framework containing 1D helical cylindered channels with diameter of 2.0 nm. The MONT has very interesting property by synergizing the functionality of nanotubes, metal-organic frameworks (MOFs), and N-heterocyclic carbenes (NHCs). The dye adsorption experiments demonstrate that the channels of the MONTs are accessible to large reagents typically used for catalysis. The postmodification of the MONT can be easily operated by unmarking the imidazolium moieties in the channel walls, which was conducted as a highly active heterogeneous catalyst for Suzuki-Miyaura and Heck coupling reactions, hydrogenation of olefins and nitrobenzene, while the constituent elements are less efficient for these reactions under the same conditions.

16.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-343969

RESUMEN

<p><b>OBJECTIVE</b>To evaluate the clinical therapeutic effect of Compound Paeonol Dripping Pill (CPDP) and its effect on the levels of plasma inflammatory mediators, including C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) and monocyte chemotactic protein-1 (MCP-1).</p><p><b>METHODS</b>Ninety patients with unstable angina were randomized by enveloping method into 3 groups equally, the conventional Western therapy group (A), the CPDP group (B), and the Tongxinluo group (C). The improvement of angina pectoris symptoms and electrocardiogram (ECG) was observed after 2 weeks of treatment and the levels of plasma CRP, IL-6, TNF-alpha and MCP-1 were measured before and after treatment.</p><p><b>RESULTS</b>The total effective rate in improving angina pectoris was 93.3% in Group B, significantly higher than that in Group A (73.3%, P <0.01) and Group C (76.7%, P <0.05), while no significant difference of ECG improvement rate was found between the three groups (P >0.05). Plasma total cholesterol and inflammation indexes were significantly lowered after treatment in Group B (P <0.05), showing a significant difference to those in the other two groups (P <0.05), but the indexes were unchanged in the other two groups (P >0.05).</p><p><b>CONCLUSION</b>Effect of CPDP is better in relieving symptoms, depressing inflammatory reaction for treatment of unstable angina patients than that of Tonxinluo Capsule and conventional Western treatment.</p>


Asunto(s)
Humanos , Acetofenonas , Usos Terapéuticos , Angina Inestable , Quimioterapia , Alergia e Inmunología , Proteína C-Reactiva , Metabolismo , Quimiocina CCL2 , Sangre , Mediadores de Inflamación , Sangre , Interleucina-6 , Sangre , Comprimidos , Factor de Necrosis Tumoral alfa , Sangre
17.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-971928

RESUMEN

@#Objective To initially evaluate the coronary arterial remodeling of the patients with coronary artery disease by use of intravascular unltrasound(IVUS).Methods 28 consecutive patients with coronary artery disease were randomly divided into the acute coronary syndrome(ACS)group(n=18)and stable angina group(n=10).The area of plaques,the area of extra-elasticity membrane(EEM)of vascellum and plaque burden as well as remodeling index(RI)of coronary arteries were measured by IVUS in two groups.The plasma levels of high sensitivity C-reactive protein(hs-CRP),matrix metalloproteinase(MMP,including MMP-2 and MMP-9),CD40 ligand(CD40L)and pregnancy associated plasma protein-A(PAPP-A)were measured by ELISA.Results The area of plaques(P=0.000),the area of EEM(P=0.003)and plaque burden of "criminal" lesions(P=0.037)in the patients of the ACS group increased more significantly than that of the control group.The incidence of high-risk plaques(P=0.028)and RI(P=0.015)in the ACS group increased more significantly than that of the control group.The positive remodeling was more common in the ACS group(P=0.040),while negative remodeling in the control group(P=0.039).The plasma levels of MMP-2(P=0.011),MMP-9(P=0.001)Pand CD40L(P=0.034)in the high-risk plaques group were significantly higher than those in the non-high-risk plaques group.There were no significant differences of the plasma levels of hs-CRP(P=0.190),MMP-2(P=0.255),MMP-9(P=0.574),CD40L(P=0.342),PPAP-A(P=0.403)and the incidence of high-risk plaques(P=0.566)in the positive and negative as well as none remodeling groups.Regression analysis showed that only the regression coefficient of ACS and stable angina by RI were significant(P<0.05),the Pregression equation was RI=0.179-0.131 group(group stands for ACS group and stable angina group).Conclusion The clinical types of coronary artery disease may be an independent predictor of the coronary arterial remodeling measured by IVUS.

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