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1.
Inorg Chem ; 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32191444

RESUMO

The unique electronic configurations of lanthanide(III) ions generate abundant electronic energy levels, resulting in the fantastic magnetic and optical multifunctional properties of lanthanide complexes. Here, 2-hydroxy-3-methoxybenzoic acid (H2MBA) was used to construct four Dy(III) and Tb(III) complexes containing two isostructural dinuclear complexes of [Ln2(HMBA)2(MBA)2(DMF)2(H2O)2]·6H2O [Ln = Dy (1), Tb (2); DMF = N,N-dimethylformamide] and two other isostructural beltlike one-dimensional-chain complexes of [NH4][Ln(HMBA)4] [Ln = Dy (3), Tb (4)]. Fluorescence measurements reveal that H2MBA can sensitize Dy(III) and Tb(III) characteristic luminescence. Furthermore, complex 3 can emit white light under UV-light irradiation originating from a dichromatic mixture of a blue emission of H2MBA and a dominating yellow emission of Dy3+ ions. Magnetic susceptibility measurements show that two Dy(III) complexes are single-molecule magnets with anisotropy barriers of 90(2) and 31(5) cm-1 for 1 and 3, respectively. The magnet-luminescence-structure correlations as well as relaxation pathways are investigated by ab initio calculations and fluorescent spectrometry.

2.
Chem Commun (Camb) ; 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32016195

RESUMO

One-dimensional zig-zag chain and two-dimensional network dysprosium(iii) single-molecule toroics with anisotropy barriers of about 5 and 31 cm-1 under a zero dc field are reported. These are the first one- and two- dimensional homometallic single-molecule toroics reported to date. Furthermore, the two complexes also display white-light emission under UV-light irradiation.

3.
Inorg Chem ; 59(1): 687-694, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31820951

RESUMO

The combination of magnetic interaction with high magnetic anisotropy provides a promising way for modulating/fine-tuning molecular magnetic behaviors. Here, we show the building block approach for the synthesis of a family of dilanthanide single-molecule magnets (SMMs) bridged with a cyanometallate starting from a monolanthanide SMM. Contingent on the central para-/diamagnetic [M(CN)6]3- (M = Fe, Co) integrated between two highly anisotropic pentagonal-bipyramid Dy(III) subunits, the remanence of magnetization is OFF/ON below 15 K and they respectively display a record reversal barrier of 659 K among d-f SMMs and 975 K among cyano-bridged SMMs.

4.
Mol Plant ; 13(2): 336-350, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31838037

RESUMO

The rubber tree, Hevea brasiliensis, produces natural rubber that serves as an essential industrial raw material. Here, we present a high-quality reference genome for a rubber tree cultivar GT1 using single-molecule real-time sequencing (SMRT) and Hi-C technologies to anchor the ∼1.47-Gb genome assembly into 18 pseudochromosomes. The chromosome-based genome analysis enabled us to establish a model of spurge chromosome evolution, since the common paleopolyploid event occurred before the split of Hevea and Manihot. We show recent and rapid bursts of the three Hevea-specific LTR-retrotransposon families during the last 10 million years, leading to the massive expansion by ∼65.88% (∼970 Mbp) of the whole rubber tree genome since the divergence from Manihot. We identify large-scale expansion of genes associated with whole rubber biosynthesis processes, such as basal metabolic processes, ethylene biosynthesis, and the activation of polysaccharide and glycoprotein lectin, which are important properties for latex production. A map of genomic variation between the cultivated and wild rubber trees was obtained, which contains ∼15.7 million high-quality single-nucleotide polymorphisms. We identified hundreds of candidate domestication genes with drastically lowered genomic diversity in the cultivated but not wild rubber trees despite a relatively short domestication history of rubber tree, some of which are involved in rubber biosynthesis. This genome assembly represents key resources for future rubber tree research and breeding, providing novel targets for improving plant biotic and abiotic tolerance and rubber production.

5.
Exp Ther Med ; 18(4): 2413-2420, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31555352

RESUMO

Anaplastic thyroid cancer (ATC) has a mean survival time of 6 months and accounts for 1-2% of all thyroid tumors. Understanding the underlying molecular mechanisms of carcinogenesis and progression in ATC would contribute to the identification of novel therapeutic targets. A previous study revealed that microRNA (miR)-599 was associated with tumor initiation and development in certain types of cancer. However, the specific functions and mechanisms of miR-599 in ATC are poorly understood. The objective of the present study was to identify its expression, function and molecular mechanism in ATC. The expression levels of miR-599 in 10 pairs of surgical specimens and human ATC cell lines were examined by reverse transcription-quantitative polymerase chain reaction. Function assays illustrated that miR-599 overexpression not only suppressed KAT-18 cell viability, proliferation and metastasis in vitro and decreased tumor growth in the tumor xenograft model but also induced cell apoptosis. Furthermore, T-cell intracellular antigen (TIA1), a tumor suppressor, was confirmed as a direct target of miR-599. It was demonstrated that TIA1 silencing rescued the inhibitory effect of migration and invasion induced by the overexpression of miR-599 in KAT-18 cells. In conclusion, the present study revealed that miR-599 inhibited ATC cell growth and metastasis via activation of TIA1. Therefore miR-599 may be a novel molecular therapeutic target for ATC.

6.
Biochem Biophys Res Commun ; 514(1): 231-238, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31029422

RESUMO

This study focuses on the role of miR-7 in colorectal cancer (CRC) cells by targeting thyroid receptor interactor protein 6 (TRIP6). Here, we report that miR-7 expression was down-regulated in colorectal cancer tissues and cell lines due to DNA hypermethylation. miR-7 overexpression significantly inhibits the proliferation and migration of CRC cells in vitro. TRIP6 was found to be a direct target gene of miR-7. The proliferation inhibition of CRC cells mediated by miR-7 could be rescued after TRIP6 overexpression in vitro and in vivo. Moreover, overexpression of TRIP6 reduced miR-7 inhibitor-mediated CRC cell migration and invasion. These findings demonstrate that miR-7 could inhibit the proliferation and migration of CRC cells by targeting TRIP6 and that miR-7 might serve as a good strategy for diagnosing and treating CRC.

7.
Inorg Chem ; 58(9): 5914-5921, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31009212

RESUMO

Four isostructural dinuclear lanthanide complexes based on 4-azotriazolyl-3-hydroxy-2-naphthoic acid (H3ATNA) and 3-hydroxy-2-naphthoic acid (H2NA) ligands, {[Ln2(HATNA)2(HNA)2(H2O)4]·6DMF} (Ln = Dy (1), Tb (2), Sm (3), Eu (4); DMF = N, N-dimethylformamide) have been prepared and characterized by X-ray diffraction crystallography, dc/ac magnetic characterization, and fluorescent spectrometry. The crystallographic data reveal dinuclear lanthanide cores of complexes 1-4, bridged by phenoxo and µ1,3 carboxyl groups. Each nine-coordinated Ln(III) ion is located in a slightly distorted monocapped square antiprism. The ligand of H3ATNA displays a unique antenna effect in complex 4. Complexes 1-3 display only two ligand-centered fluorescent emissive peaks around 450 and 600 nm, and complex 4 shows four characteristic Eu(III)-centered emission bands at 593, 618, 653, and 698 nm under excitation at 348 nm. Complex 1 exhibits single-molecule magnet behavior that is rationalized through ab initio calculations.

8.
Dalton Trans ; 48(10): 3467-3475, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30793718

RESUMO

Four 3-(tetrazol-5-yl)-5-(pyrid-2-yl)-1,2,4-triazole (H2TPT) based complexes of [Co2(TPT)2(H2O)2] (1), [Mn2(TPT)2(H2O)2] (2), [Mn(TPT)(H2O)2]n (3) and [Cu(TPT)]n (4) have been solvothermally synthesized and structurally characterized by X-ray single-crystal diffraction analysis. Complexes 1 and 2 display isostructural dinuclear structures, while complex 3 exhibits a 1D zigzag chain structure. The structural difference for 2 and 3 may be caused by 100 and 160 °C temperature-controlled conditions. Complex 4 is a 3D framework structure in which the Cu2+ ion is in square pyramid coordination geometry. Complexes 1-4 display good thermal stability evaluated by thermogravimetric analysis. Complexes 1 and 4 show very strong antiferromagnetic interactions. The electrocatalytic oxygen evolution of complexes 1-4 was tested under neutral conditions, which revealed that the four complexes possess electrocatalytic oxygen evolution activity. Complex 1 exhibits a current density of 10.0 mA cm-2 at a potential of 2.00 V (vs. RHE), presenting 50-fold improvement in specific activity over the glassy carbon electrode.

9.
Inorg Chem ; 58(2): 1301-1308, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30592214

RESUMO

A family of dinuclear dysprosium cores bridged by different ligands within a polyoxometalates (POMs) framework, (TBA)8.5H1.5[(PW11O39)2Dy2X2(H2O)2]·6H2O (X = OH (1), F (2), OAc (3); TBA = tetra- n-butylammonium), was successfully synthesized and structurally characterized. Magnetic studies indicate that the bridging ligands can significantly affect the magnetic behaviors, with 1 and 3 showing antiferromagnetic coupling and 2 bridged by fluoride ions showing ferromagnetic interaction. 1 and 2 behaved as single-molecule magnets (SMMs) with the thermally activated energy barrier of 98(5) and 74(6) cm-1 under zero dc filed, respectively, whereas no SMM behavior was observed for 3 bridged by two µ-η1:η2-acetato ligands. Notably, the low-temperature fluorescence spectra of 1-3 provide valuable information on the energy levels, which are consistent with the anisotropic barriers determined by magnetic measurements. These results offer an insight into the magneto-optical correlation. Furthermore, the effective energy barrier of 1 reaches a breakthrough among all POM-based SMMs.

10.
Dalton Trans ; 47(42): 14975-14984, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30302453

RESUMO

A new salicylaldehyde-based azo dye 5-azotriazolyl-3-methoxysalicylaldehyde (H2TMSA) and its two Ln3+ complexes {[Ln(HTMSA)3(H2O)2][Ln(HTMSA)3(DMF)(H2O)]}·15H2O (Ln = Dy(1) and Tb(2)) have been synthesized and characterized by IR, Raman, 1H NMR and single-crystal X-ray diffraction techniques. H2TMSA shows an azo form in acidic (pH < 5.05) and strong basic (pH > 12.41) conditions, and a pH-dependent azo-hydrazone tautomerism in the range of pH 5.05 to 12.41, which is demonstrated by the time-dependent density functional theory (TD-DFT) calculations. Single-crystal X-ray diffraction reveals that 1 and 2 are isostructural complexes in which the Ln3+ ions are surrounded by six oxygen atoms from three dichelate HTMSA- ligands and two oxygen atoms from two solvent molecules forming a distorted square-antiprismatic geometry. Complex 1 shows distinct slow magnetic relaxation under a zero dc field, while 2 displays field-induced slow magnetic relaxation. Ab initio calculations were performed on the two complexes to understand their magnetic anisotropy and their different magnetic dynamics.

11.
Chem Commun (Camb) ; 54(77): 10886-10889, 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30206600

RESUMO

Upon dehydration, a dinuclear Fe(ii)-Dy(iii) cluster {FeDy(H2O)2} undergoes two-step single-crystal-to-single-crystal (SCSC) transformation, giving another dinuclear cluster {FeDy(H2O)} and finally a tetranuclear cluster {Fe2Dy2}. Further, both the single crystals of {FeDy(H2O)} and {Fe2Dy2} can return to {FeDy(H2O)2} by rehydration. This multistep SCSC transformation leads to notable OFF/Part/ON switching of single-molecule magnet behaviour.

12.
Inorg Chem ; 57(12): 6773-6777, 2018 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-29863855

RESUMO

Two structurally intriguing dysprosium(III)-substituted polyoxometalates, [Dy6(ampH)4(H2O)23(ampH2)(PW11O39)2] (1) and [Dy9(CO3)3(ampH)2(H2O)12(PW10O37)6]35- (2), are assembled by the same precursor under different pH conditions. The structure of 1 contains an octahedral {Dy6(ampH)4} core, and a unique windmill-type {Dy9(CO3)3(ampH)2} for 2. Single-molecule magnet behavior is observed for 2 with a thermally activated energy barrier of 56 K and no appreciable quantum tunneling of magnetization under zero field.

13.
J Zhejiang Univ Sci B ; 19(3): 183-198, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29504312

RESUMO

Metabolic disorders are classified clinically as a complex and varied group of diseases including metabolic syndrome, obesity, and diabetes mellitus. Fat toxicity, chronic inflammation, and oxidative stress, which may change cellular functions, are considered to play an essential role in the pathogenetic progress of metabolic disorders. Recent studies have found that cells secrete nanoscale vesicles containing proteins, lipids, nucleic acids, and membrane receptors, which mediate signal transduction and material transport to neighboring and distant cells. Exosomes, one type of such vesicles, are reported to participate in multiple pathological processes including tumor metastasis, atherosclerosis, chronic inflammation, and insulin resistance. Research on exosomes has focused mainly on the proteins they contain, but recently the function of exosome-associated microRNA has drawn a lot of attention. Exosome-associated microRNAs regulate the physiological function and pathological processes of metabolic disorders. They may also be useful as novel diagnostics and therapeutics given their special features of non-immunogenicity and quick extraction. In this paper, we summarize the structure, content, and functions of exosomes and the potential diagnostic and therapeutic applications of exosome-associated microRNAs in the treatment of metabolic disorders.


Assuntos
Exossomos/fisiologia , Doenças Metabólicas/diagnóstico , Doenças Metabólicas/terapia , MicroRNAs/fisiologia , Tecido Adiposo/metabolismo , Animais , Humanos , Doenças Metabólicas/genética , Microambiente Tumoral
14.
Dalton Trans ; 47(12): 4307-4314, 2018 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-29488542

RESUMO

A 4-amino-1,2,4-triazole (NH2-trz) based linear trinuclear Fe(ii) complex of [Fe3(NH2-trz)6(SCN)4(H2O)2](SCN)2·H2O (1) has been hydrothermally synthesized by the reaction of a NH2-trz ligand with FeSO4. A single crystal of complex 1 is able to extrude one lattice water and one coordinated water, leading to another single crystal of complex 1a with a formula [Fe3(NH2-trz)6(SCN)5(H2O)](SCN) by heating. Complex 1a can be reversed to 1 upon the reabsorption of water. Single-crystal X-ray diffraction analysis reveals that these two complexes consist of a linear trinuclear core where a central Fe1 ion is coordinated to six nitrogen atoms from six bridged NH2-trz ligands and one of the terminal Fe2 ions is coordinated to five nitrogen atoms and one oxygen atom. The terminal Fe3 ion in 1 coordinates to five nitrogen atoms and one oxygen atom; however, the terminal Fe3 ion in 1a coordinates to six nitrogen atoms. Magnetic susceptibility measurements demonstrate that they exhibited gradual spin crossover (SCO) for the central Fe(ii) ion; however, different spin transition temperatures were displayed for complexes 1 and 1a (T1/2 = 202 K for 1 and 160 K for 1a). These different spin transition temperatures arise from the different intermolecular hydrogen bonding interactions in the two complexes.

15.
Dalton Trans ; 46(48): 16796-16801, 2017 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-29170784

RESUMO

A wheel-shaped Dy(iii) single-molecule magnet (SMM), supported by polyoxotungstates, Cs15K8Na12[K⊂{(AsW9O33)Dy(H2O)2}6]·71H2O (1), is described here. The polyanion of 1 possesses an idealized S6 symmetry. The effective energy barrier (68 K) obtained from magnetic studies is consistent with the deconvolution of the luminescence spectra of 1.

16.
J Clin Diagn Res ; 11(7): PE01-PE05, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28892976

RESUMO

INTRODUCTION: Duodenal lipoma is very rare with limited case reports present in literature. Owing to recent advances in endoscopy and modern imaging techniques, more cases are being diagnosed and treated. However, no systematic study of duodenal lipomas has been reported. AIM: To study the diagnosis and treatment of duodenal lipoma in a female patient and review the relative literatures to enhance the knowledge of it. MATERIALS AND METHODS: A literature search for 'duodenal lipoma' was performed on PubMed. Papers published from 1948 to 2016 in the English language were identified. Each article was then read in detail and analysed for clinical data, imaging features, diagnosis and therapy. Also, we hereby present a case of upper gastrointestinal obstruction secondary to multiple duodenal lipomas in a 67-year-old woman. The patient underwent a limited bowel resection with an uneventful recovery. RESULTS: Literature review demonstrated 59 cases of duodenal lipoma, which indicate that duodenal lipomas are rare to occur but commonly found in the second part. The peak of incidence seems to be around the fifth and seventh decade of life. Duodenal lipomas may present as gastrointestinal bleeding, abdominal pain, obstruction or upper abdominal fullness. CT, MRI, Endoscopic Ultrasound (EUS), endoscopy are highly accurate diagnostic tools. The disease could be managed by endoscopy or surgery. CONCLUSION: Our review of literature indicated duodenal lipoma is extremely rare. The symptoms are nonspecific and CT is the first choice for diagnosis. The treatment depends on the patient's condition as well as the size and position of the tumour.

17.
Inorg Chem ; 56(15): 8730-8734, 2017 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-28692252

RESUMO

A bifunctional dysprosium(III) dimer, [Dy2(HTPEIPOMe)2(OAc)4(NO3)2] (1), comprising an AIE-active (AIE = aggregation-induced emission) ligand of 2-methoxy-6-[[[4-(1,2,2-triphenylvinyl)phenyl]imino]methyl]phenol (HTPEIPOMe), was successfully synthesized. It not only behaves as a single-molecule magnet (SMM) with an energy barrier of 168(15) K at zero field but also exhibits piezochromism during the pressing-fuming cycle with switchable color, photoluminescence, and magnetic response.

18.
Chem Asian J ; 12(17): 2172-2176, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28632963

RESUMO

Hydrothermal reactions of metal nitrates and ligand bis(5-(pyridine-2-yl)-1,2,4-triazol-3-yl)methane (H2 L1 ) gave three cluster compounds, {Cr2 }, {Zn12 } and {Fe8 }. Notably, methylene group of H2 L1 was in situ oxidized either to hydroxymethylated (L2 -O)3- in the metallo-ring {Zn12 } or to a rigid carbonylated (L3 =O)2- in the screw-type {Fe8 }. In light of comparative experimental results, NO3- was deduced to be of a catalytic role in the ligand oxidation. Metal ion could be regarded as an "induced" tool for clusters generation in self-assembly process.

19.
Chem Commun (Camb) ; 53(55): 7820-7823, 2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28653076

RESUMO

Reversible crystal-to-crystal transformation between a linear trinuclear Fe(ii) complex [Fe3(NH2-trz)6(SCN)5(H2O)] (SCN)·4H2O (1, NH2-trz = 4-amino-1,2,4-triazole) and a 1D chain [Fe3(NH2-trz)6(SCN)5]n(SCN)n (1a) and the SCO behaviour change have been studied by X-ray single-crystal diffraction, magnetic measurements and DSC. Complex 1a exhibits one more SCO step at a low temperature.

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