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1.
Inorg Chem ; 63(25): 11592-11603, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38861349

RESUMO

In order to take advantage of the distinct reversible multielectron transfer properties of polyoxometalates (POMs) and increase the electron density at the active sites during the electrochemical reduction of CO2 (CO2RR), a range of transition metal-doped polyoxometalates (TMSPOMs) was entrapped within the porphyrin-based framework of PCN-224 via an encapsulation method, known as TMSPOMs@PCN-224 (TMSPOMs = [XW11O39MII(H2O)]n-, [XW11O40VIV]n-, M = CoII, MnII; X = Si, n = 6; X = P, n = 5). The central elements (Si, P) and the incorporated transition metals (VIV, CoII, and MnII) both play a role in adjusting the electronic structure and electron transfer during the CO2RR process. Remarkably, the composite material with cobalt substitution displayed significantly improved performance. Through fine-tuning the POM loading, the electrocatalytic activity was optimized, leading to an impressive Faradaic efficiency for CO production (FECO) of 89.9% for SiW11Co@PCN-224, a significant improvement compared to the 12.1% FECO of PCN-224. Furthermore, the electrochemical stability of this catalyst was demonstrated over 20 h. Comparative analyses involving six composite materials indicated a relationship between the negative charge of the polyanions and their ability to facilitate effective electron transfer, ultimately enhancing the catalyst's performance. Meanwhile, these findings were supported by density functional theory (DFT) calculations.

2.
J Environ Manage ; 359: 120782, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38669884

RESUMO

Capturing CO2 using clamshell/eggshell-derived CaO adsorbent can not only reduce carbon emissions but also alleviate the impact of trash on the environment. However, organic acid was usually used, high-temperature calcination was often performed, and CO2 was inevitably released during preparing CaO adsorbents from shell wastes. In this work, CaO-based CO2 adsorbent was greenly prepared by calcium-induced hydrogenation of clamshell and eggshell wastes in one pot at room/moderate temperature. CO2 adsorption experiments were performed in a thermogravimetric analyzer (TGA). The adsorption performance of the adsorbents obtained from the mechanochemical reaction (BM-C/E-CaO) was superior to that of the adsorbents obtained from the thermochemical reaction (Cal-C/E-CaO). The CO2 adsorption capacity of BM-C-CaO at 650 °C is up to 36.82 wt%, but the adsorption decay rate of the sample after 20 carbonation/calcination cycles is only 30.17%. This study offers an alternative energy-saving method for greenly preparing CaO-based adsorbent from shell wastes.


Assuntos
Dióxido de Carbono , Química Verde , Eliminação de Resíduos , Química Verde/métodos , Dióxido de Carbono/análise , Dióxido de Carbono/química , Hidrogenação , Temperatura , Exoesqueleto/química , Casca de Ovo/química , Eliminação de Resíduos/métodos , Adsorção
3.
J Environ Manage ; 319: 115617, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35803071

RESUMO

The preparation of clean fuel or CO2 adsorbents using industrial and domestic garbage is an alternative way of meeting global energy needs and alleviating environmental problems. Herein, H2-mixed CH4 fuel and CaO-based CO2 sorbent were first prepared in one pot by the mechanochemical reaction of pretreated clamshell or eggshell wastes (carbon and calcium source) with calcium hydride (hydrogen source) at room temperature. In the above reactions, CH4 was the sole hydrocarbon product, and its yield reached 78.23%. The H2/CH4 ratio of the produced H2-mixed CH4 fuel was tunable according to the need by changing the reaction conditions. It is inspiring that the simultaneously formed solid CaO/carbon products were efficient CaO-based sorbents, which possessed a higher CO2 adsorption capacity (49.81-58.74 wt.%) at 650 °C and could maintain good adsorption stability in 30 carbonation/calcination cycles (average activity loss per cycle of only 1.6%). The three achievements of the idea are that it can simultaneously eliminate clamshell or eggshell wastes, obtain valuable clean fuel, and acquire efficient CaO-based sorbents.


Assuntos
Compostos de Cálcio , Óxidos , Adsorção , Animais , Cálcio , Carbono , Dióxido de Carbono , Casca de Ovo , Hidrogenação , Temperatura
4.
Angew Chem Int Ed Engl ; 59(47): 20779-20793, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-32633859

RESUMO

Photo/electrocatalysis of water (H2 O) splitting and CO2 reduction reactions is a promising strategy to alleviate the energy crisis and excessive CO2 emissions. For the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and CO2 reduction reaction (CO2 RR) involved, the development of effective photo/electrocatalysts is critical to reduce the activation energy and accelerate the sluggish dynamics. Polyoxometalate (POM)-based compounds with tunable compositions and diverse structures are emerging as unique photo/electrocatalysts for these reactions as they offer unparalleled advantages such as outstanding solution and redox stability, quasi-semiconductor behaviour, etc. This Minireview provides a basic introduction related to photo/electrocatalytic HER, OER and CO2 RR, followed by the classification of pristine POM-based compounds toward different catalytic reactions. Recent breakthroughs in engineering POM-based compounds as efficient photo/electrocatalysts are highlighted. Finally, the advantages, challenges, strategies and outlooks of POM-based compounds on improving photo/electrocatalytic performance are discussed.

5.
Angew Chem Int Ed Engl ; 58(48): 17260-17264, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31557373

RESUMO

Over the past 200 years, the most famous and important heteroatom Keggin architecture in polyoxometalates has only been synthesized with Mo, W, V, or Nb. Now, the self-assembly of two phosphate (PO4 3- )-centered polyoxo-titanium clusters (PTCs) is presented, PTi16 and PTi12 , which display classic heteroatom Keggin and its trivacant structures, respectively. Because TiIV has lower oxidate state and larger ionic radius than MoVI , WVI , VV , and NbV , additional TiIV centres in these PTCs are used to stabilize the resultant heteroatom Keggin structures, as demonstrated by the cooresponding theoretical calculation results. These photoactive PTCs can be utilized as efficient photocatalysts for highly selective CO2 -to-HCOOH conversion. This new discovery indicates that the classic heteroatom Keggin family can be assembled with Ti, thus opening a research avenue for the development of PTC chemistry.

6.
Phys Chem Chem Phys ; 20(16): 11116-11122, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29623311

RESUMO

Although recent works demonstrated that some potassium compounds that can be converted to KH during ball-milling or heat-treatment have obvious effects on enhancing the dehydrogenation properties of the Li-N-H system, the effect of KH on enhancing the dehydrogenation properties of the Li-N-H system and its catalytic mechanism remain unclear. In this study, the hydrogen desorption properties of the LiNH2-LiH system with alkali metal hydrides (LiH, NaH, or KH) were investigated and discussed. We find that the three types of hydrides are effective for enhancing the hydrogen desorption properties of the LiNH2-LiH system, among which, KH shows the best effect. In comparison with the broad shaped hydrogen desorption curve of the LiNH2-LiH composite without additive, the hydrogen desorption curve of the LiNH2-LiH-0.05KH composite becomes narrow. The dehydrogenation onset temperature of the LiNH2-LiH-0.05KH composite is decreased by approximately 20 °C, and the dehydrogenation peak temperature is lowered by approximately 30 °C. Moreover, the reversibility of the LiNH2-LiH system is enhanced drastically by the addition of KH. On the basis of previous reports and present experimental results, the mechanism for the enhancement of the dehydrogenation properties in the KH-added Li-N-H system is proposed. The reason for the improvement of the hydrogen desorption kinetics is that KH has superior reactivity with NH3 and plays the role of a catalyst to accelerate hydrogen release by cyclic reactions.

7.
Hematol Oncol ; 35(4): 619-629, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27723108

RESUMO

The nasal type of extranodal natural killer/T-cell lymphoma is a rare aggressive lymphoma with poor prognosis. To discover a successful treatment, we investigated the efficacy and safety of chemotherapy with methotrexate, etoposide, dexamethasone, and polyethylene glycol-asparaginase (MESA). Three cycles of MESA were administered to 46 patients with new or relapsed/refractory natural killer/T-cell lymphoma. Complete response after 3 treatment cycles was 43.5%, the overall response rate was 87%, and 2-year overall survival was 83.4%. Complete response was significantly better for newly diagnosed patients than for patients with relapsed/refractory disease. Patients with newly diagnosed disease had a significantly better overall response rate after 1, but not after 2 or 3 treatment cycles. Overall survival and progression-free survival did not differ over 2 years. Grade 1/2 toxicities were frequent, but MESA was associated with fewer grade 3/4 events or treatment-related deaths. These results will require confirmation in larger prospective trials.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma Extranodal de Células T-NK/diagnóstico , Linfoma Extranodal de Células T-NK/tratamento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Asparaginase/administração & dosagem , Biomarcadores , China , Dexametasona/administração & dosagem , Resistencia a Medicamentos Antineoplásicos , Etoposídeo/administração & dosagem , Feminino , Humanos , Imunofenotipagem , Estimativa de Kaplan-Meier , Linfoma Extranodal de Células T-NK/mortalidade , Masculino , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Polietilenoglicóis/administração & dosagem , Prognóstico , Recidiva , Retratamento , Resultado do Tratamento , Adulto Jovem
8.
Acta Haematol ; 132(2): 177-86, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24603438

RESUMO

BACKGROUND: Acute myeloid leukemia (AML) recurrence is largely a result of multidrug resistance (MDR). We aimed to examine the role of 14-3-3ζ in AML chemosensitivity using HL-60 and vincristine-resistant HL-60/VCR cells. METHODS: The effects of 14-3-3ζ siRNA on the growth and cell cycle progression of HL-60 and HL-60/VCR cells were determined. The effect of 14-3-3ζ siRNA on topotecan (TPT)-induced apoptosis was evaluated by several assays. RESULTS: Compared to HL-60 cells, HL-60/VCR cells had increased 14-3-3ζ mRNA and protein expression. Increased mdr-1 mRNA as well as mdr-1, Bcl-2 and Mcl-1 protein expression were observed in HL-60/VCR cells. In both HL-60 and HL-60/VCR cells, 14-3-3ζ was observed in the cytoplasm and nuclear compartments. 14-3-3ζ siRNA significantly reduced HL-60 and HL-60/VCR cell growth after 48 h and increased the proportion of cells in the G0/G1 phase. Moreover, 14-3-3ζ siRNA significantly increased the sensitivity of both HL-60 and HL-60/VCR cells to TPT, possibly through the inhibition of Bcl-2, Mcl-1 and mdr-1 protein expression. CONCLUSIONS: Silencing of 14-3-3ζ increased the sensitivity of both sensitive and resistant HL-60 cells to TPT-induced apoptosis, possibly through altering the expression of apoptosis-associated proteins, suggesting that it may be a potential target for MDR AML.


Assuntos
Proteínas 14-3-3/fisiologia , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Leucêmica da Expressão Gênica , Células HL-60/enzimologia , Proteínas de Neoplasias/fisiologia , Proteínas 14-3-3/antagonistas & inibidores , Proteínas 14-3-3/biossíntese , Proteínas 14-3-3/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Apoptose/fisiologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Perfilação da Expressão Gênica , Células HL-60/efeitos dos fármacos , Humanos , Proteína de Sequência 1 de Leucemia de Células Mieloides/biossíntese , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética , Interferência de RNA , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , RNA Interferente Pequeno/farmacologia , Frações Subcelulares/metabolismo , Inibidores da Topoisomerase I/farmacologia , Topotecan/farmacologia , Vincristina/farmacologia
9.
Dalton Trans ; 52(31): 10737-10743, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37470104

RESUMO

To overcome the drawbacks of high solubility and instability of polyoxometalates (POMs) in aqueous solution and to expand their application in the electrocatalytic reduction of CO2 (ECR), we assemble sandwich-type POMs, K10[(PW9O34)2M4(H2O)2] (M = Mn, Ni, Zn, shortened as P2W18M4), into the hexagonal channel of a porphyrin-based metal-organic framework (MOF) PCN-222 to form P2W18M4@PCN-222 composites. Their ECR behavior displays polyoxoanion-dependent activity. P2W18Mn4@PCN-222 demonstrates a faradaic efficiency of 72.6% for the CO product (FECO), more than four times that of PCN-222 (FECO = 18.1%), and exhibits exceptional electrochemical stability over 36 h. P2W18Ni4@PCN-222 and P2W18Zn4@PCN-222 slightly increase (26.9%) and decrease (3.2%) in FECO, respectively. We combine the results with density functional theory (DFT) calculations to help understand the intrinsic reasons which reveals that the rate-determining step (RDS) reaction energy of P2W18Mn4@PCN-222 and P2W18Ni4@PCN-222 is significantly reduced compared to that of PCN-222. It is different in P2W18Zn4@PCN-222. Frontier molecular orbitals electron distribution results hint at directional electron transfer from P2W18Mn4/P2W18Ni4 to the porphyrin ring active center in PCN-222, promoting the electro-reduction of CO2 activity. By contrast, P2W18Zn4 may accumulate electrons from PCN-222, thus facilitating the hydrogen evolution reaction (HER). This work reveals the critical role of sandwich-type POMs in manipulating the electron transfer pathway during the electrocatalytic process. Our findings would broaden the scope of POM applications in electrochemical carbon dioxide reduction.

10.
J Oncol ; 2022: 2800488, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35422863

RESUMO

Purpose: Poly(ADP-ribose) polymerase 1 (PARP1) is necessary for single-strand break (SSB) repair by sensing DNA breaks and facilitating DNA repair through poly ADP-ribosylation of several DNA-binding and repair proteins. Inhibition of PARP1 results in collapsed DNA replication fork and double-strand breaks (DSBs). Accumulation of DSBs goes beyond the capacity of DNA repair response, ultimately resulting in cell death. This work is aimed at assessing the synergistic effects of the DNA-damaging agent temozolomide (TMZ) and the PARP inhibitor niraparib (Nira) in human multiple myeloma (MM) cells. Materials and Methods: MM RPMI8226 and NCI-H929 cells were administered TMZ and/or Nira for 48 hours. CCK-8 was utilized for cell viability assessment. Cell proliferation and apoptosis were detected flow-cytometrically. Immunofluorescence was performed for detecting γH2A.X expression. Soft-agar colony formation assay was applied to evaluate the antiproliferative effect. The amounts of related proteins were obtained by immunoblot. The combination index was calculated with the CompuSyn software. A human plasmacytoma xenograft model was established to assess the anti-MM effects in vivo. The anti-MM activities of TMZ and/or Nira were evaluated by H&E staining, IHC, and the TUNEL assay. Results: The results demonstrated that cotreatment with TMZ and Nira promoted DNA damage, cell cycle arrest, and apoptotic death in cultured cells but also reduced MM xenograft growth in nude mice, yielding highly synergistic effects. Immunoblot revealed that TMZ and Nira cotreatment markedly increased the expression of p-ATM, p-CHK2, RAD51, and γH2A.X, indicating the suppression of DNA damage response (DDR) and elevated DSB accumulation. Conclusion: Inhibition of PARP1 sensitizes genotoxic agents and represents an important therapeutic approach for MM. These findings provide preliminary evidence for combining PARP1 inhibitors with TMZ for MM treatment.

11.
Chem Commun (Camb) ; 58(15): 2512-2515, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35094039

RESUMO

To avoid the agglomeration of iron NPs and improve the dispersion of Fe SAs, we employed a mixed-ligand strategy to regulate the iron content in PCN-224(ZnxFey) and PCN-222(ZnxFey). Thanks to the sublimation of Zn and the Kirkendall effect, uniform dispersions of Fe SAs with 1.04-1.06 wt% were obtained in the pyrolysis products Zn0.5Fe0.5-N-C-224 and Zn0.5Fe0.5-N-C-222 with excellent CO2 → CO activity, super-stability, and recyclability.

12.
RSC Adv ; 10(36): 21509-21516, 2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35518741

RESUMO

CO2 capture, utilization, and storage are promising strategies to solving the problems of superfluous CO2 or energy shortage. Here, mechanochemical reduction of CO2 by a MgH2/CaH2 mixture was first performed, by which we achieve selective methanation of CO2 and acquire an effective CaO-based CO2 sorbent, simultaneously. The selectivity of methanation is near 100% and the yield of CH4 reaches 30%. Four MgO and carbon-doped CaO-based CO2 sorbents (MgO/CaO/C, MgO/2CaO/C, MgO/4CaO/C, and MgO/8CaO/C) were formed as solid products in these reactions. Among them, the MgO/4CaO/C sorbent shows high initial adsorption amount of 59.3 wt% and low average activity loss of 1.6% after 30 cycles. This work provides a novel, well-scalable, and sustainable approach to prepare an efficient inert additive-including CaO-based CO2 sorbent and selectively convert CO2 to CH4 at the same time.

13.
Dalton Trans ; 49(42): 14995-15001, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33094765

RESUMO

The eCO2RR activity is correlated to the internal structural character of the catalyst. We employed two types of structural models of porphyrin-based MOFs of PCN-222(Cu) and PCN-224(Cu) into heterogeneous catalysis to illustrate the effect of structural factors on the eCO2RR performance. The composite catalyst PCN-222(Cu)/C displays better activity and selectivity (η = 450 mV, FEHCOOH = 44.3%, j = 3.2 mA cm-2) than PCN-224(Cu)/C (η = 450 mV, FEHCOOH = 34.1%, j = 2.4 mA cm-2) for the CO2 reduction to HCOOH in the range of -0.7--0.9 V (vs. RHE) due to its higher BET surface area, CO2 uptake, and a larger pore diameter. It is interesting that PCN-224(Cu)/C displays better performance in the range of -0.4--0.6 V (vs. RHE) due to its greater heat of adsorption, Qst and a higher affinity for CO2 molecule, which could promote the capture of CO2 onto the exposed active sites. As a result, PCN-224(Cu)/C exhibits better stability for the long-term electrolysis.

14.
Inorg Chem ; 48(13): 5861-73, 2009 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-19459658

RESUMO

By introducing the flexible 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene (L(1)) and 1,4-bis(imidazole-1-ylmethyl)benzene (L(2)) ligands into the molybdate system under hydrothermal conditions, 12 novel isopolymolybdate frameworks were obtained: [CuL(1)(H(2)O)][Mo(3)O(10)] (1), [ML(1)(H(2)O)(2)][Mo(3)O(10)] [M = Cu (2), Zn (3), and Co (4)], [Cu(2)(L(1))(4)][theta-Mo(8)O(26)] (5), [Cu(4)(L(1))(4)][beta-Mo(8)O(26)](0.5)[gamma-Mo(8)O(26)](0.5).H(2)O (6), [Ag(4)(L(1))(2)][beta-Mo(8)O(26)] (7), [M(2)(L(1))(3)(H(2)O)(4)][beta-Mo(8)O(26)].2H(2)O [M = Zn (8), Co (9), and Ni (10)], and [M(4)(L(2))(4)][delta-Mo(8)O(26)] [M = Cu (11) and Ag (12)]. Compound 1 and isostructural compounds 2-4 exhibit similar three-dimensional (3D) pillar-layered structures. Compound 5 shows a novel pillar-layered framework constructed from two sorts of [CuL(1)](n) left- and right-handed helical chains and the theta-[Mo(8)O(26)](4-) polyoxoanion. Compound 6 contains two sorts of isomers of beta-[Mo(8)O(26)](4-) and gamma-[Mo(8)O(26)](4-) coexisting in one structure, which induce the formation of two sorts of ladderlike building blocks and finally the polythread structure. The cationic and anionic fragments in compound 7, the dinuclear molecular loop of [Ag(2)(L(1))(2)](2+) and beta-[Mo(8)O(26)](4-), are both linked up by single Ag ions, forming two kinds of infinite chains of [Ag(3)(L(1))(2)](n)(3n+) and [Ag-beta-Mo(8)O(26)](n)(3n-), respectively. Compounds 8-10 are isostructural and exhibit the parallel two-fold (2D-->2D) interpenetrated networks based on the beta-[Mo(8)O(26)](4-) cluster. Isostructural compounds 11 and 12 have 3D polythread penetrated frameworks based on the delta-[Mo(8)O(26)](4-) polyoxoanion. The luminescent properties of the ligands and complexes 3, 6-8, and 11-12 are investigated in the solid state.


Assuntos
Molibdênio/química , Cristalografia por Raios X , Ligantes , Modelos Moleculares , Estrutura Molecular , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 223: 117283, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31234017

RESUMO

A novel multifunctional Pb(II)-based MOF, [Pb1.5(DBPT)]2·(DMA)3(H2O)4 (1), with excellent chemical stability, was successfully assembled by connecting {Pb2O10} unit with a multi-topic polycarboxylate ligand of 3-(3,5-dicarboxylphenyl)-5-(4-carboxylphenyl)-1-H-1,2,4-triazole (H3DBPT). It exhibits dual fluorescence emissions at 380 nm (λex = 280 nm) and 540 nm (λex = 380 nm), respectively. Through the adjustable dual fluorescence emissions, it could act as a turn-off and turn-on switch for detecting N,N-dimethylacetamide (DMA) molecule. Moreover, Fe3+ ions exert luminescence quenching role on compound 1 at both excitation lengths in water, among which the quenching at λex = 280 nm is of high sensitivity (KSV = 1.2 × 105), and the quenching at λex = 380 nm is of wide-range. The sensing for metal ions of In3+, Zr4+, and Al3+ is also effective at λex = 280 nm, with the KSV constants of 1.6 × 105, 1.6 × 105, and 4.3 × 104, respectively. More importantly, a series of nitroaromatic compounds (TNP, 2,4,6-trinitrophenol; 4-NA, 4-nitroaniline; NB, nitrobenzene) and nitro-based drugs (MNZ, metronidazole; DMZ, dimetridazole) could be detected at both excitation lengths, demonstrating the advantage of broad range response of fluorescence sensing. Thanks to the excellent chemical stability and unusual dual emission luminescence properties for chemical detection of various metal ions, nitro-based molecules and DMA solvent, the Pb-based MOF reported in this work is, therefore, a very promising multi-response sensor.


Assuntos
Acetamidas/química , Estruturas Metalorgânicas/química , Metais/química , Nitrocompostos/química , Íons , Solventes/química , Espectrometria de Fluorescência , Temperatura , Difração de Raios X
16.
Int J Hematol ; 87(2): 152-166, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18288567

RESUMO

This study investigated the effects of human bone marrow fibroblastoid stromal cell line (HFCL) on the proliferation, differentiation and chemosensitivity of acute myeloid leukemia cells (AML) in vitro coculture. By setting up coculture system of sensitive U937, HL-60 cell line and multidrug-resistant (MDR) HL-60/VCR cells in direct contact with human bone marrow fibroblastoid stromal cell line HFCL, or separated by transwell, the proliferation of AML cells cocultured with HFCL cells was inhibited, compared with AML cells alone. And NBT positive cells increased slightly. The percentage of G1 phase cells of AML cells cocultured with HFCL cells was higher than that without HFCL cells, and that of S phase cells was lower. The expression of CD11b and CD14 increased. Meanwhile HL-60 and HL-60/VCR cells treated by TPT were observed to have apoptosis characteristic morphological changes. The proportion of G0/G1 HL-60 and HL-60/VCR cells treated with TPT increased and the sub-G1 increased. The percentage of Annexin V-positive cells and apoptotic cells increased with expression of activated Caspase-3 and the reduced expression of Bcl-2. But when they were cocultured with HFCL cells, the percentage of Annexin V-positive cells and apoptotic cells decreased and sub-G1 reduced. After indirect contact with HFCL cells the expression of activated Caspase-3 decreased and the expression of Bcl-2 increased. After direct contact with HFCL cells for 96 h, the expression levels of 582 genes in HL-60 cells were up-regulated, and 1,323 genes were down-regulated at least twofold by Affymetrix GeneChip Human Genome U133 set A. The expression change in some genes, such as HL14, was confirmed by RT-PCR and northern blot. In a word, HFCL cells could inhibit the proliferation, induce the monocytic differentiation of U937, HL-60 and HL-60/VCR cells, and prevent TPT-induced apoptosis in HL-60 and HL-60/VCR cells via modulation of Bcl-2 and active Caspase-3. Many genes might take part in the influence of HFCL cells on AML cells, which may give important insights into the interaction of bone marrow stromal cells and leukemic cells.


Assuntos
Apoptose , Diferenciação Celular , Proliferação de Células , Perfilação da Expressão Gênica , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Células da Medula Óssea , Linhagem Celular Tumoral , Técnicas de Cocultura , Regulação para Baixo , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Células Estromais , Regulação para Cima
17.
Dalton Trans ; 46(41): 14286-14292, 2017 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-29018849

RESUMO

Using the methodology of extension of reduced transition metal-grafted ε-Keggin polyoxoanions with two types of terphenyl-based tricarboxylates of H3L1 (3,5',3''-position substitution) and H3L2 (4,5',4''-position substitution) we isolated two (3,6)-connected 3D polyoxometalate-based metal-organic frameworks, [TBA]3[H3PMo12O40][Zn4L2] (1, YZU-105), and [TPA]3[H3PMo12O40][Zn4L1]·0.5H2O (2, YZU-106) (H3L1 = [1,1';3',1''-terphenyl]-3,5',3''-tricarboxylic acid; H3L2 = [1,1';3',1''-terphenyl]-4,5',4''-tricarboxylic acid; TBA = tetrabutylammonium; TPA = tetrapropylammonium). In both compounds, the building block was the dimerized form of Zn4-{ε-H3PMo12O40}. Such dimerization left six anchoring points for each dimer and, as a result, a 6-connected node was formed. Compounds 1 and 2 exhibited topologies of (4·85)3(4·82)6 and (65·10)3(63)6, respectively. This work illustrates that use of tri-carboxylate substitutions in different positions (3,5',3''-position/4,5',4''-position) in tripodal terphenyl-based ligands allows different extents of twisting of the peripheral aromatic ring with respect to the central ring, thereby giving rise to different extending directions and symmetries.

18.
Oncol Res Treat ; 39(1-2): 45-52, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26891121

RESUMO

BACKGROUND: Extranodal natural killer (NK)/T cell lymphoma (ENKTL) is an aggressive non-Hodgkin's lymphoma with high mortality and poor prognosis despite radiotherapy and chemotherapy. The current analysis aimed to assess the pathological features, clinical features, and prognostic indicators of ENKTL. MATERIAL AND METHODS: 120 ENKTL patients were analyzed for pathologic diagnosis and clinical disease manifestations from April 2007 to October 2012. Complete remission, 2-year overall survival, and progression-free survival were analyzed. RESULTS: Compared with the nasal group, a greater percentage of patients in the non-nasal group intended to receive autologous stem cell transplantation had Epstein-Barr virus (EBV) DNA, Ann Arbor stage IV, Ki-67 expression ≥ 60%, and abnormal ferroprotein and ß-microglobulin levels. The rate of complete remission in the non-nasal group was higher than that in the nasal group. The overall survival rate was 74.9% at 24 months. Patients receiving chemotherapy and radiotherapy were more likely to have disease progression compared with patients who received chemotherapy or radiotherapy alone. CONCLUSIONS: Further understanding the pathological and clinical features of ENKTL will be critical for moving forward. Ki-67, ß-microglobulin, EBV DNA, and primary site prognostic indicators may be useful to stratify patients into different risk groups, to gain insight into patient-specific treatments, and to potentially improve survival.


Assuntos
Quimiorradioterapia/mortalidade , Linfoma Extranodal de Células T-NK/mortalidade , Linfoma Extranodal de Células T-NK/terapia , Neoplasias Nasais/mortalidade , Neoplasias Nasais/terapia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia/estatística & dados numéricos , Criança , China/epidemiologia , Intervalo Livre de Doença , Feminino , Humanos , Linfoma Extranodal de Células T-NK/diagnóstico , Masculino , Pessoa de Meia-Idade , Neoplasias Nasais/diagnóstico , Prevalência , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Taxa de Sobrevida , Adulto Jovem
19.
Dalton Trans ; 44(3): 1435-40, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25428699

RESUMO

Replacing the metal ions (or metal clusters) in routine MOFs with size-matched polyoxoanions to construct POM-based MOF materials (POMOF) combining well-defined crystalline structures, high surface area, regular and tunable cavities is the great challenge in the current POM chemistry area. In this work, we report a 2-fold interpenetrated porous POMOF, [TBA]6[H3PMo12O40]2[Zn8(BTB)2]·(∼35H2O), which exhibits effective catalytic activity towards bromate reduction, using the methodology of extension for the reduced transition-metal-grafted ε-Keggin polyoxoanions with an expanded tripodal bridging ligand of H3BTB. The simultaneous TGA/DSC-MS technique was applied in this work to identify the evolved gases and was proved to be an effective method for analysing the decomposition process.

20.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 23(3): 718-21, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26117024

RESUMO

OBJECTIVE: To explore the effect of valproic acid(VPA) on anti-myeloma activity of Doxorubicin(DOX) or Melphalan(MEL) and its related mechanism. METHODS: Human multiple myeloma(MM) cells were treated with VPA of non-toxic dose in absence and presence of DOX or MEL at different concentrations (ie. IC10, IC20, IC40). The cell proliferation was detected by MTT method. Western blot was used to detect the expression levels of autophagy-related proteins (LC3, ATG5, ATG7) and acetylated histone H4K16ac. RESULTS: Cell proliferation inhibition markedly increased in VPA plus DOX or MEL as compared with DOX or MEL alone (P<0.05). Both LC3 and H4K16ac expression levels in co-treatment were between VPA and DOX or MEL treated alone. Importantly, VPA of non-toxic dose not only augmented the anti-myeloma activity of DOX or MEL, but also down-regulated the autophagy-related protein expression and increases H4K16ac protein levels. CONCLUSION: H4K16ac can inhibit the transcription of autophagy-related genes, The VPA enhance the anti-myeloma activity of DNA-damaging drugs, at least in part, via H4K16ac-mediated suppression of cytoprotective autophagy.


Assuntos
Autofagia , Dano ao DNA , Mieloma Múltiplo , Acetilação , Linhagem Celular Tumoral , Proliferação de Células , DNA , Doxorrubicina , Humanos , Ácido Valproico
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