RESUMEN
This study aims to prepare co-loaded indocyanine green(ICG) and elemene(ELE) nano-emulsion(NE) in situ gel(ICG-ELE-NE-gel) and evaluate its physicochemical properties and antitumor activity in vitro. ICG-ELE-NE-gel was prepared by aqueous phase titration and cold solution methods, followed by characterization of the morphology, particle size, corrosion, and photothermal conversion characteristics. The human breast cancer MCF-7 cells were taken as the model, combined with 808 nm laser irradia-tion. Cell inhibition rate test and cell uptake test were performed. ICG-ELE-NE was spherical and uniform in size. The average particle size and Zeta potential were(85.61±0.35) nm and(-21.4±0.6) mV, respectively. The encapsulation efficiency and drug loading rate were 98.51%±0.39% and 10.96%±0.24%, respectively. ICG-ELE-NE-gel had a good photothermal conversion effect and good photothermal stability. The dissolution of ICG-ELE-NE-gel had both temperature and pH-responsive characteristics. Compared with free ELE, ICG-ELE-NE-gel combined with near-infrared light irradiation significantly enhanced the inhibitory effect on MCF-7 cells and could be uptaken in large amounts by MCF-7 cells. ICG-ELE-NE-gel was successfully prepared, and its antitumor activity was enhanced after 808 nm laser irradiation.
Asunto(s)
Neoplasias de la Mama , Proliferación Celular , Emulsiones , Verde de Indocianina , Humanos , Verde de Indocianina/química , Células MCF-7 , Emulsiones/química , Proliferación Celular/efectos de los fármacos , Femenino , Tamaño de la Partícula , Geles/química , Nanopartículas/química , Composición de Medicamentos/métodos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Portadores de Fármacos/químicaRESUMEN
Iron-catalyzed asymmetric amination of C(sp3 )-H bonds is appealing for synthetic applications due to the biocompatibility and high earth abundance of iron, but examples of such reactions are sparse. Herein we describe chiral iron complexes of meso- and ß-substituted-porphyrins that can catalyze asymmetric intramolecular C(sp3 )-H amination of aryl and arylsulfonyl azides to afford chiral indolines (29 examples) and benzofused cyclic sulfonamides (17 examples), respectively, with up to 93 % ee (yield: up to 99 %) using 410â nm light under mild conditions. Mechanistic studies, including DFT calculations, for the reactions of arylsulfonyl azides reveal that the Fe(NSO2 Ar) intermediate generated in situ under photochemical conditions reacts with the C(sp3 )-H bond through a stepwise hydrogen atom transfer/radical rebound mechanism, with enantioselectivity arising from cooperative noncovalent interactions between the Fe(NSO2 Ar) unit and the peripheral substituents of the chiral porphyrin scaffold.
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Catalytic oxidation using manganese corrole is a hot topic of contemporary porphyrin chemistry, in which PhIO, TBHP, PhI(OAc)2, KHSO5 and m-CPBA are usually used as oxidants. This article reports the first selective oxidation of styrene to benzaldehyde using a manganese(III) corrole catalyst and sodium nitrite (NaNO2) as oxidant and cocatalyst at room temperature. The yield was 158.1% in air and 96.5% under a nitrogen atmosphere, showing oxygen might be involved in the reaction and that NaNO2 is an oxygen source and cocatalyst in the system. The peripheral electron-withdrawing substituents of the manganese corrole were favorable to the catalytic reaction. Radical inhibition and H218O experiments proved that the catalytic reaction was a free radical and hydrolysis-involved reaction.
Asunto(s)
Metaloporfirinas , Porfirinas , Benzaldehídos , Catálisis , Manganeso , Nitrógeno , Oxidantes , Oxidación-Reducción , Oxígeno , Nitrito de Sodio , EstirenoRESUMEN
A single-pixel neural network object classification scenario in the sub-Nyquist ghost imaging system is proposed. Based on the neural network, objects are classified directly by bucket measurements without reconstructing images. Classification accuracy can still be maintained at 94.23% even with only 16 measurements (less than the Nyquist limit of 1.56%). A parallel computing scheme is applied in data processing to reduce the object acquisition time significantly. Random patterns are used as illumination patterns to illuminate objects. The proposed method performs much better than existing methods for both binary and grayscale images in the sub-Nyquist condition, which is also robust to environment noise turbulence. Benefiting from advantages of ghost imaging, it may find applications for target recognition in the fields of remote sensing, military defense, and so on.
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Activation of dioxygen (O2) in enzymatic and biomimetic reactions has been intensively investigated over the past several decades. More recently, O-O bond formation, which is the reverse of the O2-activation reaction, has been the focus of current research. Herein, we report the O2-activation and O-O bond formation reactions by manganese corrole complexes. In the O2-activation reaction, Mn(V)-oxo and Mn(IV)-peroxo intermediates were formed when Mn(III) corroles were exposed to O2 in the presence of base (e.g., OH-) and hydrogen atom (H atom) donor (e.g., THF or cyclic olefins); the O2-activation reaction did not occur in the absence of base and H atom donor. Moreover, formation of the Mn(V)-oxo and Mn(IV)-peroxo species was dependent on the amounts of base present in the reaction solution. The role of the base was proposed to lower the oxidation potential of the Mn(III) corroles, thereby facilitating the binding of O2 and forming a Mn(IV)-superoxo species. The putative Mn(IV)-superoxo species was then converted to the corresponding Mn(IV)-hydroperoxo species by abstracting a H atom from H atom donor, followed by the O-O bond cleavage of the putative Mn(IV)-hydroperoxo species to form a Mn(V)-oxo species. We have also shown that addition of hydroxide ion to the Mn(V)-oxo species afforded the Mn(IV)-peroxo species via O-O bond formation and the resulting Mn(IV)-peroxo species reverted to the Mn(V)-oxo species upon addition of proton, indicating that the O-O bond formation and cleavage reactions between the Mn(V)-oxo and Mn(IV)-peroxo complexes are reversible. The present study reports the first example of using the same manganese complex in both O2-activation and O-O bond formation reactions.
Asunto(s)
Manganeso/química , Oxígeno/química , Porfirinas/química , Alquenos/química , Hidrógeno/química , Cinética , Oxidación-ReducciónRESUMEN
Porphyrin is a kind of photosensitizer for photodynamic therapy of cancer. Many porphyrin derivatives have been used in clinical treatment. Human Serum Albumin (HSA) is the carrier of drug transportation. Therefore, investigation on the interaction of porphyrin with HSA is very important to understand the pharmacokinetic of the porphyrin. In this paper, a new water-soluble carboxyl porphyrins, meso-tetrakis(carboxyl) zinc(â ¡) porphyrin (2-Zn), was synthesized and characterized. Its interaction with human serum albumin (HSA)was investigated by UV-Vis absorption spectra, fluorescence spectra, circular dichroism (CD) spectra and molecular modeling. The results indicated that the fluorescence quenching of HSA by 2-Zn was a static process with the quenching constants are 1.96×104 L·mol-1 (298 K) and 1.37×104 L·mol-1 (310 K) and the binding constants were calculated to be 1.93×104 L·mol-1 (298 K) and 1.50×104 L·mol-1 (310 K). According to the Van't Hoff equation, the thermodynamic parameters were characterized by negative enthalpy (ΔH=-16.132 kJ·mol-1) and positive entropy (ΔS=27.905 J·mol-1·K-1), which indicated that 2-Zn binds with HSA mainly via electrostatic interaction along with the hydrogen bonding and hydrophobic interaction. Site marker competitive binding experiment confirmed that 2-Zn mainly binds at site â ¡. The distance between HSA and the receptor (2-Zn) and the efficiency energy transfer were obtained to be 4.01 nm and 0.163 respectively, based on the Forster theory on resonance energy transfer. Synchronous fluorescence, absorption and CD spectroscopy showed that the interaction of HSA with 2-Zn induced a conformational change of protein, and the amount of α-helical structures were decrease. Furthermore, the binding details between 2-Zn and HSA were further studied with the molecular docking, which was in good agreement with the site marker competitive binding experiments and thermodynamic parameters.
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Agua/química , Sitios de Unión , Dicroismo Circular , Transferencia de Energía , Fluorescencia , Humanos , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Simulación del Acoplamiento Molecular , Porfirinas , Unión Proteica , Albúmina Sérica , Albúmina Sérica Humana , Espectrometría de Fluorescencia , Termodinámica , ZincRESUMEN
OsRac5 belongs to the rice Rho of plants family, and acts as the molecular switch in the signal pathway which is pivotally involved in the rice fertility control. One of its putative partners, OsMY1, was isolated by yeast two-hybrid screening from rice panicle cDNA library. Bioinformatics analysis shows that OsMY1 contains a coiled-coil domain which generally appeared in the partners of Rho GTPases. By yeast two-hybrid assay, it is confirmed that OsMY1 binds both the wild type (WT) and constitutively active (CA) OsRac5, but does not interact with dominantly negative OsRac5. In addition, the interactions between OsMY1 and WT-OsRac5 or CA-OsRac5 in vivo are demonstrated by bimolecular fluorescence complementation assay. Using PCR-mediated sequence deletion and point mutation of OsMY1, the interaction between OsMY1 and OsRac5 was identified to be mediated by the coiled-coil domain in OsMY1, and their binding was quantified by O-nitro-phenyl-ß-D-galactopyranoside assay. Real-time PCR shows that OsMY1 and OsRac5 are coordinately expressed in rice leaves and panicles with similar expression patterns. Our results suggest that OsMY1 is an important target of OsRac5 and that these two genes are involved in the same biological processes in rice growth and development.
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Oryza/genética , Proteínas de Plantas/aislamiento & purificación , Factores de Transcripción/genética , Proteínas de Unión al GTP rho/genética , Regulación de la Expresión Génica de las Plantas , Biblioteca de Genes , Oryza/crecimiento & desarrollo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Homología de Secuencia de Aminoácido , Factores de Transcripción/aislamiento & purificación , Factores de Transcripción/metabolismo , Técnicas del Sistema de Dos Híbridos , Proteínas de Unión al GTP rho/metabolismoRESUMEN
As nitrogen analogues of iron-oxo species, high-valent iron-imido species have attracted great interest in the past decades. FeV-alkylimido species are generally considered to be key reaction intermediates in Fe(III)-catalyzed C(sp3)âH bond aminations of alkyl azides but remain underexplored. Here, it is reported that iron-corrole (Cor) complexes can catalyze a wide range of intramolecular CâH amination reactions of alkyl azides to afford a variety of 5-, 6- and 7-membered N-heterocycles, including alkaloids and natural product derivatives, with up to 3880 turnover numbers (TONs) and excellent diastereoselectivity (>99:1 d.r.). Mechanistic studies including density functional theory (DFT) calculations and intermolecular hydrogen atom abstraction (HAA) reactions reveal key reactive FeV-alkylimido intermediates. The [FeV(Cor)(NAd)] (Ad = adamantyl) complex is independently prepared and characterized through electron paramagnetic resonance (EPR), resonance Raman (rR) measurement, and X-ray photoelectron spectroscopy (XPS). This complex is reactive toward HAA reactions with kinetic isotope effects (KIEs) similar to [Fe(Cor)]-catalyzed intramolecular CâH amination of alkyl azides.
RESUMEN
Photophysical properties of five kinds of porphyrins (H2TMPyP, ZnTMPyP, PdTMPyP, H2TPPS, and ZnTPPS) complexed with model DNAs (ctDNA and dGMP) have been investigated using steady-state absorption, circular dichroism (CD), and femtosecond transient absorption spectroscopy. Upon addition of ctDNA (or dGMP), larger hypochromism and red shifts are observed for H2TMPyP and PdTMPyP compared to the other samples. The steady-state measurements have suggested that the binding modes of H2TMPyP-ctDNA and PdTMPyP-ctDNA are partial intercalation and full intercalation, respectively, while ZnTMPyP-ctDNA shows outside groove binding. No significant interaction was observed between both H2TPPS and ZnTPPS with two kinds of DNA. Upon excitation of the porphyrins into the higher excited state S2 (Soret band), the appearance of the transient absorption from â¼500 to â¼620 nm at about 0.05 ps in H2TMPyP-ctDNA, H2TMPyP-dGMP, and PdTMPyP-dGMP indicates the occurrence of the electron transfer (ET) from guanine to H2TMPyP and PdTMPyP. The forward ET are extremely fast (kf ≥ 1.0 × 1013 s-1), and the backward ET rates are â¼5.6 × 1012 and â¼4.0 × 1012 s-1, respectively. The complexation with DNA may lead to the shorter lifetime of the fluorescence of H2TMPyP and PdTMPyP.
Asunto(s)
Porfirinas , Agua , Dicroismo Circular , ADN , ElectronesRESUMEN
New food packaging has shown research significance in the face of increasing demand for high-quality foods and growing attention paid to food safety. In this study, ginger essential oil microcapsule composite films were prepared by combining microcapsules prepared by a complex coacervation method with gelatin films, and the mechanical properties and active functions of the composite films were analyzed. Fourier-transform infrared spectroscopy and differential scanning calorimetry confirmed the successful encapsulation of ginger essential oil. The scanning electron microscopy of the composite films showed the microcapsules and gelatin film matrix were highly compatible. During the entire storage period, the antioxidant capacity of the ginger essential oil microcapsule films weakened more slowly than ginger essential oil microcapsules and could be maintained at a relatively high level for a long time. The microcapsule films had excellent inhibitory effects on Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. Therefore, the direct addition of microcapsules to a film matrix can broaden the application range of microcapsules and increase the duration of the release of active ingredients. Ginger essential oil microcapsule films are potential biodegradable food packaging films with long-lasting activity.
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The development of novel, efficient and nontoxic photosensitizers (PSs) is a challenging task for photodynamic therapy (PDT). In our previous study, corrole had been demonstrated to be a promising PS in PDT for cancer cells. In this paper, a novel electron-deficient flat phosphorus tris(ethoxycarbonyl) corrole (1-P) was synthesized and characterized. In vitro photodynamic activities and toxicity of 1-P in HepG2 xenograft tumours was evaluated by standard assay. The results shown 1-P displayed a potential efficient and low-toxic PS, which suggesting this kind of corrole is a powerful and promising antitumor PS for PDT. In addition, the potential anti-tumour mechanism study of 1-P was also investigated by the apoptosis antibody array, immunohistochemical and western blotting assay (WB) experiments, we found that the PDT activity of 1-P can degrade SIRT1 (an important deacetylase), and activate the Fas signal pathway to inhibit the growth of liver cancer cells.
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Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Ratones , Fósforo/farmacología , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/toxicidad , Porfirinas/farmacología , Sirtuina 1/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Receptor fas/metabolismoRESUMEN
Two new nonconjugated porphyrin-coumarin dyads with different orientations with respect to donor-acceptor entities and their zinc complexes were synthesized. Single-crystal structures of the free-base porphyrin-coumarin dyads were successfully resolved. The absorption spectra of the dyads were linear combinations of the spectra of their corresponding monomers, indicating a negligible electronic communication between the coumarin and porphyrin moieties. However, the fluorescence emission of the coumarin entity in all of the dyads was quenched significantly compared to that of pristine coumarin, and this effect was attributed to intramolecular energy transfer from the coumarin to the porphyrin. The energy transfer kinetics from the coumarin to the porphyrin was shown to be fast ( kFörster = 1.13 × 1013 s-1 for the ortho-isomer and 5.13 × 1011 s-1 for the para-isomer in DMF) and efficient (transfer efficiency ca. 96-97%). Transient absorption studies showed that the excited state decay process (S2 â S1*, S1* â S1, S1 â S0, and S1 â T1) of the para-isomer was faster than that of the ortho-isomer in DMF. All of the synthesized dyads were tested for their interactions with ct-DNA and photocleavage activity toward PBR322-DNA. The results revealed that all of the dyads interacted with ct-DNA via only an external groove-binding mode; the binding constants were calculated to be 3.24 × 105 (3a), 3.05 × 105 (3b), 3.04 × 105 (4a), and 4.88 × 105 (4b), and the photocleavage activity was in the order 4b < 3b < 4a < 3a. Furthermore, only the zinc complexes of the porphyrin-coumarin dyads could be absorbed by tumor cells (A549). These complexes were mainly localized in the cytoplasm, exhibited red fluorescence, and showed low cytotoxicity toward all of the tumor cell lines tested. The results showed that these zinc complexes of the porphyrin-coumarin dyads have potential applications in fluorescence imaging.
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Cumarinas/química , Porfirinas/química , Células A549 , Supervivencia Celular/efectos de los fármacos , Complejos de Coordinación/química , Complejos de Coordinación/metabolismo , Complejos de Coordinación/farmacología , ADN/química , ADN/metabolismo , División del ADN/efectos de los fármacos , Transferencia de Energía , Humanos , Conformación Molecular , Plásmidos/química , Plásmidos/metabolismo , Teoría Cuántica , Oxígeno Singlete/metabolismo , Espectrometría de Fluorescencia , Zinc/químicaRESUMEN
Ketamine is a non-competitive antagonist of N-methyl-D-aspartate receptors (NMDARs). Growing evidence suggests that a single dose of ketamine produces a series of rapid and remarkable antidepressant properties. However, the mechanisms remain unclear. In our study, the antidepressant properties of a single dose of ketamine (10â¯mg/kg, i.p.) in mice exposed to chronic unpredictable stress (CUS) were assessed using the open-field test (OFT) and the forced swimming test (FST). Early growth response 1 (Egr-1) and postsynaptic density protein 95 (PSD-95) mRNA and protein expression levels were examined using qRT-PCR and western blot, respectively. Dendritic spine density in the CA1 region of the hippocampus was detected by Golgi staining. AMPAR currents in hippocampal slices were measured by electrophysiology. Our study showed that CUS induced a significant depression-like behavior accompanied by an upregulation of Egr-1 and downregulations of PSD-95, spine density, and AMPAR currents in the hippocampus, and a single dose of ketamine rapidly restored these changes. Interestingly, a single dose of Ro-25-6981 (an GluN2B antagonist, 10â¯mg/kg, i.p.) or Egr-1 siRNA, but not NVP AAM077 (an GluN2A antagonist, 10â¯mg/kg, i.p.), could produce the same antidepressant effects as ketamine. These data demonstrate that ketamine may produce its rapid antidepressant effects by downregulating the expression of Egr-1 via blocking GluN2B in the hippocampus.
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Antidepresivos/farmacología , Trastorno Depresivo/tratamiento farmacológico , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Ketamina/farmacología , Receptores de N-Metil-D-Aspartato/metabolismo , Animales , Espinas Dendríticas/efectos de los fármacos , Espinas Dendríticas/metabolismo , Espinas Dendríticas/patología , Trastorno Depresivo/metabolismo , Trastorno Depresivo/patología , Modelos Animales de Enfermedad , Homólogo 4 de la Proteína Discs Large/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Proteína 1 de la Respuesta de Crecimiento Precoz/antagonistas & inhibidores , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Hipocampo/patología , Masculino , Ratones Endogámicos C57BL , ARN Mensajero/metabolismo , Receptores AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Estrés Psicológico/tratamiento farmacológico , Estrés Psicológico/metabolismo , Estrés Psicológico/patología , Técnicas de Cultivo de Tejidos , IncertidumbreRESUMEN
Corroles have been previously demonstrated to be a new and promising photosensitizer (PS) in photodynamic therapy (PDT) for cancer cells. This research reported the preparation of an electron-deficient flat gallium(iii) tris(ethoxycarbonyl)corrole (1-Ga). Its in vitro PDT activities towards different cancer cell lines were examined, and the best PDT activity was observed in A549 cell lines. 1-Ga could penetrate the cell membrane rapidly and exhibit remarkable photo-cytotoxicity. 1-Ga can induce A549 cell apoptosis via ROS-mediated mitochondrial pathways, in which p38 and sirt-1 proteins play a key role. A PTD test in vivo showed that 1-Ga can significantly reduce the growth of A549 xenografted tumor cells without an obvious loss of mice weight upon PDT treatment.