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1.
Inorg Chem ; 55(21): 10999-11005, 2016 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-27767307

RESUMEN

Two luminescent Cd(II) metal-organic frameworks (MOFs) were prepared from electron-rich π-conjugated fluorescent ligands. They are isostructural with sql nets. Their strong luminescences can be quenched by a series of nitroaromatic explosives. Notably, MOF 1 shows highly selective and sensitive detection of 4-nitrophenol (4-NP), while MOF 2 exhibits good responses toward picric acid (PA) compared with other nitroaromatic explosives. This different order of quenching efficiency is because there are H-bonding interactions between MOF 1 and 4-NP, while MOF 2 lacks these H-bonding interactions. MOF 1 displays highly selective and sensitive detection of 4-NP with the high quenching constant (6.74× 104 M-1) and low detection limit (34.48 ppb), which is better than those of known MOFs. MOF 1 and MOF 2 have highly sensitive and selective detection of 4-NP and PA in the practical application, respectively.

2.
Signal Transduct Target Ther ; 6(1): 395, 2021 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-34785655

RESUMEN

Aberrant activation of the TGF-ß/SMAD signaling pathway is often observed in hepatocellular carcinoma (HCC). Whether lncRNA regulates the TGF-ß/SMAD signaling remains largely unknown. Here, we identified an oncogenic lncRNA that was upregulated in HCC and was transcriptionally induced by TGF-ß (named lnc-UTGF, lncRNA upregulated by TGF-ß). Upon TGF-ß stimulation, SMAD2/3 bound to the lnc-UTGF promoter and activated lnc-UTGF expression. In turn, the TGF-ß/SMAD signaling was augmented by overexpressing lnc-UTGF, but was inhibited by silencing lnc-UTGF. Mechanism investigations revealed that lnc-UTGF interacted with the mRNAs of SMAD2 and SMAD4 via complementary base-pairing, resulting in enhanced stability of SMAD2/4 mRNAs. These data suggest a novel TGF-ß/SMAD/lnc-UTGF positive feedback circuitry. Subsequent gain- and loss-of-function analyses disclosed that lnc-UTGF promoted the migration and invasion of hepatoma cells, and this effect of lnc-UTGF was attenuated by repressing SMAD2/4 expression or by mutating the SMAD2/4-binding sites in lnc-UTGF. Studies using mouse models further confirmed that in vivo metastasis of hepatoma xenografts was inhibited by silencing lnc-UTGF, but was enhanced by ectopic expression of lnc-UTGF. The lnc-UTGF level was positively correlated with the SMAD2/4 levels in xenografts. Consistently, we detected an association of lnc-UTGF upregulation with increase of SMAD2, SMAD4, and their metastasis effector SNAIL1 in human HCC. And high lnc-UTGF level was also significantly associated with enhanced metastasis potential, advanced TNM stages, and worse recurrence-free survival. Conclusion: there exists a lnc-UTGF-mediated positive feedback loop of the TGF-ß signaling and its deregulation promotes hepatoma metastasis. These findings may provide a new therapeutic target for HCC metastasis.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Proteína Smad2/metabolismo , Proteína Smad4/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Animales , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Células HEK293 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Ratones , Metástasis de la Neoplasia , Proteínas de Neoplasias/genética , Proteína Smad2/genética , Proteína Smad4/genética , Factor de Crecimiento Transformador beta/genética
3.
Cell Death Dis ; 11(4): 276, 2020 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-32332695

RESUMEN

Elevated endoplasmic reticulum (ER) stress is frequently observed in cancers, whereas sustained ER stress may trigger apoptosis. How cancer cells escape from ER stress-induced apoptosis remain unclear. Here, we found that a pseudogene-derived lncRNA, Golgin A2 pseudogene 10 (GOLGA2P10), was frequently upregulated in HCC tissues and significantly elevated in hepatoma cells treated with ER stress inducers, such as tunicamycin and thapsigargin. Higher GOLGA2P10 level was correlated with shorter recurrence-free survival of HCC patients. Upon ER stress, CHOP directly bound to the promoter of GOLGA2P10 and induced its transcription via the PERK/ATF4/CHOP pathway. Interestingly, the ER stress inducer-stimulated apoptosis was promoted by silencing GOLGA2P10 but was antagonized by overexpressing GOLGA2P10. Both gain- and loss-of-function analyses disclosed that GOLGA2P10 increased BCL-xL protein level, promoted BAD phosphorylation, and conferred tumor cells with resistance to ER stress-induced apoptosis. Moreover, BCL-xL overexpression or BAD knockdown abrogated the apoptosis-promoting effect of GOLGA2P10 silencing. Consistently, the Ser75Ala mutation in BAD, which caused phosphorylation-resistance, further enhanced the promoting effect of BAD in tunicamycin-induced apoptosis. These results suggest that ER stress induces GOLGA2P10 transcription through the PERK/ATF4/CHOP pathway, and upregulation of GOLGA2P10 protects tumor cells from the cytotoxic effect of persistent ER stress in tumor microenvironment by regulating Bcl-2 family members, which highlight GOLGA2P10 as a potential target for anticancer therapy.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Genes bcl-2/genética , ARN Largo no Codificante/genética , Femenino , Humanos , Masculino , Transducción de Señal , Factor de Transcripción CHOP/metabolismo , Transfección , Microambiente Tumoral
4.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 1): m16-7, 2009 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-21579917

RESUMEN

In the title coordination polymer, [Zn(5)(µ(3)-OH)(2)(1,4-CDC)(4)](n) (1,4-CDCH(2) = 1,4-cyclo-hexa-nedicarboxylic acid) or [Zn(5)(C(8)H(10)O(4))(4)(OH)(2)](n), the asymmetric unit comprises one half of an octa-hedrally coordinated ZnO(6) complex unit (site symmetry ) and two five-coordinate ZnO(5) complex units, together with two µ(3)-bridging hydroxido ligands and four 1,4-CDC ligands (comprising two whole mol-ecules and four inversion-related half-molecules). The ZnO(6) unit consists of four carboxyl-ate O donors (two bridging) and two hydroxido O donors (both bridging three Zn centres) [Zn-O range 2.065 (3)-2.125 (3) Å]. Each of the ZnO(5) units [one capped tetra-hedral, the other square-pyrimidal; Zn-O range 1.928 (3)-2.338 (3) Å] has one hydroxido O donor and four carboxyl O donors from three different 1,4-CDC carboxyl-ate O donors (one bridging). Infinite (ZnO)(n) inorganic chains run parallel to the a axis and are interconnected by the organic ligands into a three-dimensional structure.

5.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): m873, 2009 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-21583338

RESUMEN

The asymmetric unit of the title complex, [Zn(C(10)H(6)NO(2))(2)(H(2)O)](n), consists of one quinoline-4-carboxyl-ate anion, half of a Zn(2+) cation and half of a coordinated water mol-ecule. The cation and the water O atom have crystallographically imposed inversion and twofold rotation symmetry, respectively. The metal centre displays an elongated ZnO(6) octa-hedral coordination geometry provided by the O atoms of four anions at the equatorial plane and two axial water mol-ecules. Each anion and water mol-ecule act as bridges between Zn(II) cations, forming a polymeric chain parallel to [001]. The chains are further linked into a three-dimensional framework through O-H⋯N hydrogen bonds.

6.
Dalton Trans ; 46(7): 2332-2338, 2017 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-28138686

RESUMEN

Four Cd(ii)-based compounds (1-4) were synthesized from solvothermal reactions involving the in situ aldimine condensation of an o-diamino-functionalized precursor 3,6-di(4H-imidazol-4-yl)benzene-1,2-diamine (L), Cd(NO3)2·4H2O and aldehyde. Two modes of cycloaddition ([4 + 1] cycloaddition and [4 + 2] cycloaddition) occurred during condensation, causing the in situ generation of two benzimidazole derivative ligands (L1 and L3) and a quinoxaline derivative ligand (L2). Furthermore, the chemical selectivity of the condensation was studied, where the condensation of o-diamino and the aldehyde is more stable and easy to operate. This strategy enriches the synthesis method of MOFs. Additionally, compound 2 containing uncoordinated quinoxaline N atoms showed excellent luminescent sensitivity for Fe3+ detection.

8.
Dalton Trans ; 43(33): 12528-35, 2014 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-25004124

RESUMEN

The solvothermal reactions of 1,1'-oxybis[3,5-di-4-pyridine]-benzene (L) and transition metal cations (Co and Ni) afford five novel coordination polymers in the presence of flexible bridging ligands (4,4'-H2nba = 4,4'-dicarboxydiphenylamine, H2cam = d-camphoric acid, 4,4'-H2sdb = 4,4'-sulfonyldibenzoic acid, H2chdc = 1,4-trans-cyclohexanedicarboxylic acid), namely {[Co2L2(OH)2(nba)]·2DMF}n (), {[CoL(cam)(H2O)]}n (), {[Co3(L)(4,4'-sdb)3(H2O)]·1.5CH3CN·4H2O}n (), {[Ni3(L)(4,4'-sdb)3(H2O)]·1.5CH3CN·4H2O}n (), and {[Ni2L2(chdc)2(H2O)2]·(H2O)3}n () (DMF = N,N-dimethylformamide). Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectroscopy, and powder X-ray diffraction. Complex reveals a 2-fold interpenetrating three-dimensional (3D) framework with the Schläfli symbol {4·8·10(4)}{4·8·10} topology. Compound crystallizes in the achiral space group with the d-camphorate ligand racemized. Compounds and reveal similar structure with the {3·4(4)·6}{3(2)·4(8)·5(9)·6(9)} topology based on a linear trinuclear building block M3(OOCR)6 (M = Co(ii) or Ni(ii)). Compound is a wavy sheet, where both carboxylate and L ligands act as bidentate ligands. Moreover, UV-Visible absorption spectra of complexes , and the magnetic properties of have been investigated.


Asunto(s)
Cobalto/química , Níquel/química , Polímeros/síntesis química , Difracción de Rayos X , Cobalto/metabolismo , Cristalografía por Rayos X/métodos , Ligandos , Níquel/metabolismo , Polímeros/metabolismo , Difracción de Rayos X/métodos
9.
Bing Du Xue Bao ; 26(2): 134-42, 2010 Mar.
Artículo en Zh | MEDLINE | ID: mdl-20480643

RESUMEN

The complete genome of encephalomyocarditis virus (EMCV)strain GXLC isolated from swine was sequenced and analyzed. Five overlapped gene fragments covering the entire open reading frame (ORF) were amplified by RT-PCR, and the 3'-untranslated region (UTR) and 5'-UTR were amplified by the 3'-rapid amplification of cDNA ends (RACE) and 5'-RACE method, respectively. The genome sequences of strain GXLC were obtained by assembling the sequences of RT-PCR-generated cDNA fragments. The length of the complete genome was 7 725 nucleotides (nt). The homology comparison and phylogenetic analysis of the nucleotide and deduced amino acid sequences between strain GXLC and other EMCV strains available in GenBank were performed. The results showed that the complete genome identity between GXLC strain and the strains from China, i.e. GX0601, GX0602, BJC3 and HB1 and the strains from other countries, i.e. CBNU, K3, K11, TEL-2887A, EMCV-R and PV21 was over 99%. The phylogenetic trees based on the complete genome, the structural protein or the non-structural protein gene sequences revealed that the tree topology was similar. All the EMCV strains could be divided into two groups: group I and group II, and group I could be subdivided into subgroup Ia and subgroup Ib. The strains from swine belonged to subgroup Ia or Ib, and the strains from mice belonged to subgroup Ia, while the strains from Sus scro fa belonged to group II. Strain GXLC, together with other EMCV isolates from China, belonged to subgroup Ia.


Asunto(s)
Infecciones por Cardiovirus/veterinaria , Virus de la Encefalomiocarditis/genética , Genoma Viral , Enfermedades de los Porcinos/virología , Animales , Infecciones por Cardiovirus/virología , Línea Celular , Virus de la Encefalomiocarditis/clasificación , Virus de la Encefalomiocarditis/aislamiento & purificación , Datos de Secuencia Molecular , Sistemas de Lectura Abierta/genética , Filogenia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Especificidad de la Especie , Porcinos , Destete
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