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1.
J Transl Med ; 19(1): 126, 2021 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-33771165

RESUMEN

BACKGROUND: As the fourth leading cause of cancer-related death in the world, the therapeutic effect and 5-year overall survival of hepatocellular carcinoma (HCC) are not optimistic. Previous researches indicated that the disorder of PRDXs was related to the occurrence and development of cancers. METHODS: In this study, PRDXs were found in various tumor cell lines by CCLE database analysis. The analysis results of UALCAN, HCCDB and Human Protein Atlas databases showed the expression of PRDXs mRNA and protein in HCC tissues was dysregulated. Besides, UALCAN was used to assess the correlations between PRDXs mRNA as well as methylation levels and clinical characterization. RESULTS: High expression of PRDX1 or low expression of PRDX2/3 suggested poor prognosis for HCC patients which was demonstrated by Kaplan-Meier Plotter. The genetic alterations and biological interaction network of PRDXs in HCC samples were obtained from c-Bioportal. In addition, LinkedOmics was employed to analyze PRDXs related differentially expressed genes, and on this basis, enrichment of KEGG pathway and miRNAs targets of PRDXs were conducted. The results indicated that these genes were involved in several canonical pathways and certain amino acid metabolism, some of which may effect on the progression of HCC. CONCLUSIONS: In conclusion, the disordered expression of some PRDX family members was associated with the prognosis of HCC patients, suggesting that these PRDX family members may become new molecular targets for the treatment and prognosis prediction of HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroARNs , Carcinoma Hepatocelular/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/genética , Pronóstico
2.
Chemistry ; 20(15): 4273-83, 2014 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-24590571

RESUMEN

A series of thioether-functionalised imidazolium salts have been prepared and characterized. Subsequent reaction of the thioether-functionalised imidazolium salts with iodomethane affords imidazolium-sulfonium salts composed of doubly charged cations and two different anions. Imidazolium-sulfonium salts containing a single anion type are obtained either by a solvent extraction method or by anion exchange. The imidazolium-sulfonium salts undergo a methyl-transfer reaction on exposure to water, giving rise to a new, singly charged imidazolium salt with iodide introduced at the 2-position of the imidazolium ring. Crystal structures of some of the imidazolium-sulfonium salts were determined by X-ray crystallography providing the topology of the interactions between the dications and the anions. Electrospray ionization mass spectrometry and quantum-chemical calculations were used to rationalise the relative strength of these interactions.

3.
Inorg Chem ; 53(6): 2757-9, 2014 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-24559131

RESUMEN

A dimeric Keggin polyoxometalate, [Cu(bpy)(µ2-OH)]4[(H2O)(bpy)2HPW11Cu2O39]2·2CH3CH2OH·10H2O (1), constructed from two dicopper(II)-substituted monovacant Keggin polyoxoanions bridged by a Cu4 cluster, has been hydrothermally synthesized. Magnetic analysis indicates predominantly an antiferromagnetic interaction between copper(II) centers. Compound 1 also shows very high catalytic activity for the esterification of phosphoric acid with equimolar lauryl alcohol to monoalkyl phosphate ester.

4.
Chemistry ; 18(38): 11909-12, 2012 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-22890800

RESUMEN

Magnetic personality: A pentavalent vanadium source was employed to prepare the largest highly reduced polyoxovanadate cluster by virtue of the reducing power of 1,2-diaminocyclohexane under hydrothermal conditions. The new non-classical triangle-shaped cluster shows good catalytic selectivity for the oxidation of styrene and exhibits ferrimagnetic interactions that could make it a promising magnetic material.


Asunto(s)
Aniones/química , Ciclohexilaminas/química , Nanopartículas/química , Estireno/química , Vanadio/química , Catálisis , Cristalografía por Rayos X , Magnetismo , Estructura Molecular , Compuestos Organometálicos/química , Oxidación-Reducción
5.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 7): o2001, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22807830

RESUMEN

In the title mol-ecule, C(11)H(6)F(2)N(2)O(2), the benzene and pyridine rings form a dihedral angle of 32.57 (6)°. The nitro group is tilted with respect to the pyridine ring by 12.26 (9)°. An intra-molecular C-H⋯F hydrogen bond is present. In the crystal, mol-ecules inter-act through π-π stacking inter-actions [centroid-centroid distances = 3.7457 (14) Å], forming columnar arrangements along the b axis. The crystal packing is further enforced by inter-molecular C-H⋯O and C-H⋯N hydrogen bonds.

6.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): o1672-3, 2012 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-22719467

RESUMEN

In the title compound, C(21)H(21)N(3)O(2), the pyridine rings and the benzene ring lie in a propeller arrangement around the central tertiary amine N atom. The dihedral angles formed by the benzene ring with the pyridine rings are 61.0 (3) and 49.6 (3)°, while the dihedral angle between the pyridine rings is 69.7 (3)°. The mol-ecular conformation is stabilized by intramolecular bifurcated O-H⋯N hydrogen bonds. In the crystal, inversion dimers are formed via pairs of C-H⋯N hydrogen bonds.

7.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 7): m871, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22807720

RESUMEN

In the title complex, [Ni(C36H26Cl4N4O2)]·C3H6O, two 2,4-dichloro-benzoyl groups are grafted onto the methine groups of the Ni(II) complex Ni(tmtaa) (H2tmtaa = 5,7,12,14-tetra-methyl-4,11-dihydro-dibenzo[b,i][1,4,8,11]tetra-aza-cyclo-tetra-decine). The complex has the shape of a saddle. The Ni atom is tetra-coordinated by the four N atoms of the macrocycle, forming a slightly tetra-hedrally distorted square-planar geometry. The metal is displaced by 0.0101 (8) Šfrom the N4 mean plane. The aromatic rings of the 2,4-dichloro-benzoyl groups form dihedral angles of 87.1 (2) and 82.1 (2)° with the N4 mean plane.

8.
Biosens Bioelectron ; 215: 114553, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35868121

RESUMEN

Exosomes have been widely used in early cancer diagnosis as promising cancer biomarkers due to their abundant tumor-specific molecular information. In this study, we developed a sensitive and straightforward surface-enhanced Raman scattering (SERS) aptasensor to detect exosomes based on gold nanostars-decorated molybdenum disulfide (MoS2) nanocomposites (MoS2-AuNSs). ROX-labeled aptamers (ROX-Apt) were assembled on MoS2-AuNSs surface as recognition probes that specifically bind with transmembrane protein CD63 (a representative surface marker on exosomes). Thus obvious ROX Raman signals were obtained through the synergistic Raman enhancement effect of AuNSs and MoS2 nanosheet. In presence of exosomes, ROX-Apt is preferentially tethered onto exosomes and released from the surface of nanocomposites, resulting in a decrease of the SERS signal. Expectedly, the as-fabricated SERS aptasensor was capable of detecting exosomes in a wide range from 55 to 5.5 × 105 particles µL-1 with a detection limit of 17 particles µL-1. Moreover, the aptasensor exhibited accepted stability and potential clinical applicability.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Exosomas , Nanopartículas del Metal , Neoplasias Gástricas , Técnicas Biosensibles/métodos , Oro , Humanos , Molibdeno , Espectrometría Raman/métodos , Neoplasias Gástricas/diagnóstico
9.
Inorg Chem ; 50(22): 11561-7, 2011 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-22026738

RESUMEN

A series of novel ionic liquids composed of imidazolium, pyridinium, pyrrolidinium, and ammonium cations with tricyanomethanide or tetracyanoborate anions were prepared. The ionic liquids were characterized by NMR and IR spectroscopy and ESI-mass spectrometry, and their physical properties were investigated. Solid state structures of the N-propyl-N-methylpyrrolidinium and triethylpropylammonium tetracyanoborate salts were obtained by single crystal X-ray diffraction. The salts that are liquid at room temperature were evaluated as electrolyte additives in dye-sensitized solar cells, giving rise to efficiencies 7.35 and 7.85% under 100 and 10% Sun, respectively, in combination with the standard Z907 dye.

10.
Dalton Trans ; 50(34): 11975-11985, 2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34378599

RESUMEN

Metal-organic frameworks (MOFs) as proton-conductive materials have attracted increasing attention due to their applications in proton-exchange membrane fuel cells. While the majority of the MOFs are based on transition metals, group II metals with unusual configurations have received relatively less attention. In this work, we selected three tetrazole-based acetic acids, N,N-di(2-carboxymethyltetrazol-5-yl)amine (H2L1), 1,3,5-tri(2-carboxymethyltetrazol-5-yl)benzene (H3L2), and 4,5-di(tetrazol-5-yl)imidazolylacetic acid (H3L3), as ligands and prepared three MOFs with barium(ii) ions: [Ba2(L1)2(H2O)5]·2H2O (1), (Me2NH2)[Ba(L2)(H2O)]·3H2O (2), and [Ba3(µ2-H2O)(L3)2(H2O)3]·2H2O (3). Ba-MOFs have been unambiguously characterized by elemental, FT-IR spectroscopy and single-crystal X-ray diffraction analyses. In the solid state, 2D MOF 1 with two nine-coordinated Ba(ii) centers shows a rare hula hoop-like geometry at the Ba1 atom and a distorted tricapped trigonal prismatic geometry around the Ba2 one. Unusual sphenocorona geometry is also found in MOF 2 with a ten-coordinated Ba(ii) ion. In MOF 3, three different Ba(ii) ions coexist with two nine-coordinated Ba1 and Ba2 displaying a muffin-like configuration and a distorted tricapped trigonal prism geometry, respectively, and an eight-coordinated Ba3 having a distorted biaugmented trigonal prism geometry. In addition, MOF 2 exhibits an unprecedented trinodal 3,7,7-connected 3D network with the Schläfli symbol (37·46·52·62·74)(37·46·52·63·73)2(63) and MOF 3 displays a novel trinodal 4,5,9-connected 3D framework with the Schläfli symbol (421·615)(45·6)(48·62). Due to the presence of extensive hydrogen bonded networks consisting of dimethyl ammonium and water molecules in the 1D channels, MOF 2 shows a high proton conductivity of 4.47 × 10-3 S cm-1 at 85 °C and 98% relative humidity (RH).

11.
Chemistry ; 16(22): 6473-81, 2010 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-20455221

RESUMEN

A series of fluorescent imidazolium-based salts containing the cation [AnCH(2)MeIm](+) (in which An = anthracene and Im = the imidazolium cation) with Cl(-), BF(4)(-), PF(6)(-), SO(3)CF(3)(-), [N(CN)(2)](-), [N(SO(2)CF(3))(2)](-), or PhBF(3)(-) anions have been prepared and characterized. X-ray diffraction analysis of four of the salts reveals a number of C-H...X-type (X = O, N, F) hydrogen bonds between the hydrogen atoms from the imidazolium ring and in some cases from the anthracene ring with the electronegative atoms of the anions. Additionally, C-H...pi interactions can be found in all the salts analyzed by X-ray diffraction, whereas pi-pi stacking is observed only in the salt containing the phenyltrifluoroborate anion. Fluorescence emission analysis in acetonitrile shows that the fluorescence of these salts varies significantly according to the nature of the anion, and correlates to the extent of ion pairing present in solution. Photodimerization of these salts was observed, and in one case a dimer has been isolated and characterized by X-ray crystallography.

12.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 32(4): 449-55, 2010 Aug.
Artículo en Zh | MEDLINE | ID: mdl-20868609

RESUMEN

OBJECTIVE: To investigate the cytotoxic effect of multi-walled carbon nanotubes (MWCNTs) on human liver L02 cells and its relevant mechanism. METHODS: MWCNTs, carboxyl modification MWCNTs (MWCNTs-COOH), and hydroxyl modification MWCNTs (MWCNTs-OH) were characterized by transmission electron microscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. The carbon nanotubes at concentrations of 12.5, 25, 50, 100, and 200 µg/ml were incubated with human liver L02 cells for 24, 48 and 72 hours, respectively. The cell viability was evaluated by water soluble tetrazolium salts assay and the intercellular reactive oxygen species induced by the carbon nanotubes were detected by 2', 7'-dichlorodihydrofluorescein diacetate method. RESULTS: Transmission electron microscope showed that the average outside diameters (10 to 20 nm) and the average length (10 to 30 µm) of the three MWCNTs were similar. Scanning electron microscope indicated that the three MWCNTs had a similar surface topography. X-ray photoelectron spectroscopy demonstrated that the MWCNTs-COOH and MWCNTs-OH had relatively high peak areas at 289 and 286ev, respectively,indicating that they have been modified by carboxyl and hydroxyl groups,respectively. Water soluble tetrazolium salts assay showed that the MWCNTs-COOH was less cytotoxic when compared to MWCNTs which demonstrated to be slightly more cytotoxic than MWCNTs-OH. The capability to induce increase in intracellular reactive oxygen species was in the following order: MWCNTs > MWCNTs-COOH > MWCNTs-OH. CONCLUSIONS: Modification of MWCNTs with carboxyl group and hydroxyl group improves the biocompatibility of MWCNTs to some extents. MWCNTs-COOH has better compatibility than MWCNTs at the low concentration,and MWCNTs-OH showed better compatibility than MWCNTs after 48 hours. Different mechanisms may be involved in the interaction between cells and the MWCNTs with different chemical surfaces.


Asunto(s)
Hepatocitos/efectos de los fármacos , Nanotubos de Carbono/toxicidad , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Hepatocitos/metabolismo , Humanos , Nanotubos de Carbono/química , Especies Reactivas de Oxígeno/metabolismo
13.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 10): o2526, 2009 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-21577971

RESUMEN

The title compound, C(20)H(14)N(4)O(2), crystallizes in the ortho-rhom-bic system with a crystallographic twofold axis through the N-N bond. The mol-ecule is non-planar and the dihedral angle between two amide groups is 74.9 (2)°. An intra-molecular N-H⋯N hydrogen bond is present. In the crystal, the mol-ecules are packed in chains running along the c axis through inter-molecular N-H⋯O hydrogen bonds. These chains are further stabilized by inter-molecular C-H⋯O hydrogen bonds and C-H⋯π inter-actions leading to the formation of a three-dimensional network.

14.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 5): o1177-8, 2009 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-21583979

RESUMEN

In the mol-ecule of the title compound, C(15)H(14)N(4), the triazole ring is oriented at dihedral angles of 30.8 (2) and 67.4 (2)° with respect to the pyridine and benzene rings, respectively. The crystal structure is stabilized by C-H⋯N hydrogen-bonding inter-actions, forming chains of mol-ecules along [01].

15.
Dalton Trans ; 47(22): 7463-7470, 2018 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-29786101

RESUMEN

The catalytic activities of eight copper(i) halide clusters assembled from copper(i) halide and ferrocenyltelluroethers, 1-8, were investigated in C-N formation under various conditions. A catalytic procedure using poly(ethylene glycol) (PEG-400) as a greener alternative organic solvent has been developed. The PEG-400/5 system can achieve 99% targeted yield with a mild reaction temperature and short reaction time. After the isolation of the products by extraction with diethyl ether, this PEG-400/cluster system could be easily recycled. Spectroscopic studies elucidate a stepwise mechanism: firstly, proton-coupled electron transfer (PCET) involving the transfer of an electron from Cu+ and a proton from imidazole results in the formation of a labile penta-coordinated Cu2+ and aryl radical; the following effective electron transfer from the ferrocene unit reduces Cu2+ and forms the target product; finally, the ferrocenium unit is reduced by the I- anion. The merits of this eco-friendly synthesis are the efficient utilization of reagents and easy recyclability.

16.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 28(4): 486-91, 2006 Aug.
Artículo en Zh | MEDLINE | ID: mdl-16995298

RESUMEN

OBJECTIVE: To evaluate the effects of arginine modified chitosan or hexadecylated modified chitosan as gene carriers on the cellular uptake by vascular smooth muscle cells and its in vitro cytotoxicity. METHODS Plasmid DNA was labeled with alpha-32P-dATP and complexed with the modified chitosans or unmodified chitosan to form nanoparticle complexes by complex coacervation method. Uptake of all kinds of chitosan/ DNA nanoparticle complexes (CNC) by A10 cells was measured by beta-liquid scintillation counting. The in vitro cytotoxicity of the CNC was evaluated by the 3-[4,5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay. RESULTS: The diameters of the CNC ranged from 55.9-174.9 nm and the zeta potentials were from 10. 8 mV for the arginine modified chitosan/DNA nanoparticle complexes (ACNC) to 1.8 mV for the hexadecylated chitosan/DNA nanoparticle complexes (HCNC). The cellular uptake of the modified chitosan/ DNA nanoparticle complexes (MCNC) by A10 cells increased significantly when compared with the unmodified chitosan/DNA nanoparticle complexes (UCNC) (P < 0.05), with the HCNC at N/P ratio of 1:1 and the ACNC at ratio of 8:1 showing the highest cellular uptake (1.3 fold higher than UCNC, P < 0.05). MCNC were much less cytotoxic when compared with Lipofectamine 2000-DNA nanoparticles. CONCLUSION: DNA nanoparticle complexes prepared with either arginine or hexadecylated modified chitosan can improve the cellular uptake of the DNA, while the in vitro cytotoxicity of both of the modified chitosan is much less than that of Lipofectamine 2000.


Asunto(s)
Arginina/farmacología , Quitosano/farmacología , ADN/farmacología , Vectores Genéticos , Animales , Complejo Antígeno-Anticuerpo , Quitosano/química , Ácido Cítrico/análogos & derivados , Ácido Cítrico/farmacología , Citotoxicidad Inmunológica , Nanopartículas , Ratas
17.
Dalton Trans ; 44(19): 9281-8, 2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-25913506

RESUMEN

Three 3D lanthanide­organic frameworks (LOFs), [LnL(HCO2)(DMF)]n (Ln = Eu (1), Gd (2), Dy (3); H2L = 2,2'-dimethoxy-4,4'-biphenyldicarboxylic acid), have been prepared by the solvothermal reaction of Ln(NO3)3·6H2O and H2L in DMF­H2O mixed solvent. Crystallographic data show that LOFs 1­3 are isomorphous and crystallize in the orthorhombic space group Pna21. Each Ln(III) is eight-coordinated to four O atoms from four L2− ligands, one O atom from the DMF molecule and three O atoms from HCO2−. The adjacent Ln(III) ions are linked by the carboxylate groups of the L2− ligands and HCO2− to form a 1D inorganic rod-shaped [Ln(CO2)2(HCO2)]n chain as a secondary building unit (SBU). The infinite 1D chains are interconnected by the biphenyl groups, giving rise to a 3D framework along the c axis. LOFs 1­3 are the first neutral Ln-carboxylate/HCO2− chain-based sra-nets. 1 exhibits characteristic luminescence of Eu3+ upon 343 nm excitation. The investigation of magnetic properties shows very weak ferromagnetic interactions (J = 0.0092(3) cm−1) between Gd(III) ions in 2 with a Gd­O­Gd bridging angle of 125.6(1)°, and θ = −1.9(2) K in 3 due to thermal depopulation of the Stark levels of Dy(III) ions and/or the possible antiferromagnetic interactions between Dy(III) ions in contrast to the single-ion behavior observed in 1.

18.
Phytochemistry ; 97: 88-95, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24256579

RESUMEN

Five hetisane-type C20-diterpenoid alkaloids, trichodelphinines A-E, one delnudine-type C20-diterpenoid alkaloid, trichodelphinine F and three known flavonoids, quercetin, quercetin 3-O-ß-D-glucopyranoside, and quercetin 3-O-ß-D-glucopyranoside-7-O-α-L-arabinopyranoside, were isolated from whole plants of Delphinium trichophorum Franch. Their structures were elucidated on the basis of extensive spectroscopic analysis, including HSQC, HMBC, (1)H-(1)H COSY, NOESY and X-ray crystallographic analysis, and from chemical evidence. The cytotoxic activities of the diterpenoid alkaloids were evaluated using the MTT method, and the IC50 values of their cytotoxicity against A549 cancer cells ranged from 12.03 to 52.79 µM.


Asunto(s)
Alcaloides/aislamiento & purificación , Antineoplásicos/aislamiento & purificación , Delphinium/química , Diterpenos/aislamiento & purificación , Flavonoides/aislamiento & purificación , Alcaloides/química , Alcaloides/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Cristalografía por Rayos X , Diterpenos/química , Diterpenos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Flavonoides/química , Flavonoides/farmacología , Glucósidos/química , Glucósidos/aislamiento & purificación , Humanos , Concentración 50 Inhibidora , Conformación Molecular , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Quercetina/análogos & derivados , Quercetina/química , Quercetina/aislamiento & purificación , Tibet
19.
J Pharm Anal ; 3(6): 447-451, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29403853

RESUMEN

A HPLC-ELSD method was developed and validated for simultaneous determination of five Hetisane-type diterpenoid alkaloids in a Tibetan traditional herbal medicine, "Gebu Dilu" (Herba Delphinii), using a Kromasil C18 column (250 mm×4.6 mm, 5 µm) with the mobile phase consisting of acetonitrile and 0.1% triethylamine in gradient (detected by evaporative light scattering detector). The linear ranges of five compounds were determined and method validation was evaluated completely. The established method is rapid and accurate with high repeatability, and can be applied for the quality control of Herba Delphinii.

20.
Chem Commun (Camb) ; 49(84): 9728-30, 2013 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-23784519

RESUMEN

A novel 2-D coordination polymer constructed from high nuclearity nanosized Ho48 clusters was synthesised and structurally characterized using single-crystal X-ray analysis. The Ho48 cluster core with a charming waist drum-like structure was templated by CO3(2-) ions, and bridged by Ho-N bonds to get a 2-D coordination polymer.

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