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1.
Inorg Chem ; 61(51): 21047-21054, 2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36512697

RESUMO

Two new extended polyoxometalate (POM) architectures based on lanthanide-incorporated polyoxoniobate (Ln-incorporated PONb) cages, namely, H4[CuII(en)2]4{K4(H2O)2[CuII(en)2]5[CuII5(trz)2(en)4(OH)2][Dy2CuII2(en)2(CO3)3(H2O)2(OH)3][Dy(H2O)4][DyNb23O68(H2O)4]2}·60H2O (1, en = ethylenediamine) and H20[CuII(en)2]4{[CuII(en)2]4[Dy2(C2O4)(H2O)4]2[(Nb32(OH)4(H2O)3O89]2}·54H2O (2), have been successfully synthesized and structurally characterized, demonstrating a feasible strategy to develop functional POM materials. In addition, the proton conductivity and magnetic behaviors of both 1 and 2 were studied.

2.
Inorg Chem ; 58(7): 4055-4058, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30868872

RESUMO

A rare and novel Cr-substituted polyoxoniobate (PONb), [Cr2.5Nb27.5O66(OH)20(H2O)2]7-, has been synthesized by a combination of hydrothermal and conventional solution methods. The PONb shows an unknown tetrameric structure, which is the largest Cr-containing PONb to date. Interestingly, every two PONb tetramers can be joined together by alkali-metal cations to form a discrete cubelike ionic cluster. The obtained PONb not only enriches the very limited members of the Cr-substituted PONb family but also exhibits high ionic conductivity.

3.
Inorg Chem ; 57(5): 2472-2479, 2018 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-29442500

RESUMO

Four seven-nuclearity 3d-4f heterometallic cluster {Fe6LnO28} substituted polyoxometalates (HPz)11K4Fe6Ln(µ3-O)2(B-α-GeW9O34)2(GeW6O26)· xH2O (1-Ln, Pz = piperazine, Ln = Tb, Dy, Ho, Er for x = 27, 25, 25, 24, respectively) have been hydrothermally prepared and structurally characterized by single-crystal X-ray diffraction, powder X-ray diffraction, infrared spectrometry, thermogravimetric analyses, elemental analyses, and electrospray ionization mass spectrometry. Single-crystal X-ray diffraction analyses revealed that 1-Ln contain an unprecedented banana-shaped polyanion constructed from an iron-lanthanide heterometallic {Fe6LnO28} cluster, two trilacunary {B-α-GeW9O34} units, and one hexalacunary {GeW6O26} fragment. The magnetic susceptibility surveying proved the presence of antiferromagnetic coupling in 1-Ln.

4.
Angew Chem Int Ed Engl ; 57(28): 8572-8576, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29809317

RESUMO

A protein-sized (ca. 4.2×4.2×3.6 nm3 ) non-biologically derived molecule {Nb288 O768 (OH)48 (CO3 )12 } (Nb288 ) containing up to 288 niobium atoms has been obtained, which is by far the largest and the highest nuclearity polyoxoniobate (PONb). Particularly, in terms of metal nuclearity number, Nb288 is the second largest cluster so far reported in classic polyoxometalate chemistry (V, Mo, W, Nb, and Ta). Nb288 can be described as a giant windmill-like cluster aggregate of six nanoscale high-nuclearity PONb units {Nb47 O128 (OH)6 (CO3 )2 } (Nb47 ) joined together by six additional Nb ions. Interestingly, the 47-nuclearity Nb47 units generated in situ can be isolated and bridged by copper complexes to form an inorganic-organic hybrid three-dimensional PONb framework, which exhibits effective catalytic activity for hydrolyzing nerve agent simulant of dimethyl methylphosphonate. The unique Nb47 cluster also provides a new type of topology to very limited family of Nb-O clusters.

5.
Angew Chem Int Ed Engl ; 56(51): 16288-16292, 2017 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-29105960

RESUMO

A series containing the highest nuclearity polyoxoniobate (PONb) nanoclusters, ranging from dimers to tetramers, has been obtained. They include one 114-nuclear {Li8 ⊂Nb114 O316 }, one 81-nuclear {Li3 K⊂Nb81 O225 }, and one 52-nuclear {H4 Nb52 O150 }. The Nb nuclearity of these PONbs is remarkably larger than those of all known high-nuclearity PONbs (≤32). Furthermore, the introduction of 3d Cu2+ ions can lead to the generation of extended inorganic-organic hybrid frameworks built from novel, high-nuclearity, nanoscale heterometallic PONb building blocks {H3 Cu3 Nb78 O222 } or {H3 Cu4 (en)Nb78 O222 }. These building blocks also contain the largest number of Nb centers of any heterometallic PONbs reported to date. The synthesis of new-type PONbs has long been a challenging subject in PONb chemistry.

6.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(9): 956-60, 2015 Sep.
Artigo em Zh | MEDLINE | ID: mdl-26412178

RESUMO

OBJECTIVE: To investigate the effects of high-volume hemofiltration (HVHF) on hemodynamics, vasoactive factors, and vascular endothelial permeability in children with septic shock by a comparative analysis. METHODS: Thirty-six children who were diagnosed with septic shock between January 2013 and September 2014 were randomly divided into control and observation groups (n=18 each). Children in the control group were treated with the standard-volume hemofiltration (SVHF), while children in the observation group were treated with HVHF. The hemodynamic indices and levels of vasoactive factors including 6-keto-prostaglandin F1α (6-keto-PGF1α), thromboxane B2 (TXB2), soluble E-selectin (sE-selectin), and endothelium-derived relaxing factor (EDRF) were determined before and after treatment. In addition, the effects of ultrafiltrate on endothelial cell permeability were assessed. RESULTS: Compared with the control group, the observation group had significantly higher mean arterial pressure, significantly higher blood oxygen saturation, and a significantly lower heart rate after treatment (P<0.05). The levels of TXB2 and sE-selectin were significantly lower in the observation group than in the control group (P<0.05), while the levels of 6-keto-PGF1α and EDRF were significantly higher in the observation group than in the control group (P<0.05). Compared with the control group, the ultrafiltrate significantly attenuated the transepithelial electrical resistance in the observation group (P<0.05). CONCLUSIONS: Compared with SVHF, HVHF is a more effective approach for improving the hemodynamics and levels of vasoactive factors and reducing the vascular endothelial permeability in children with septic shock.


Assuntos
Permeabilidade Capilar , Hemodinâmica , Hemofiltração , Choque Séptico/fisiopatologia , Criança , Pré-Escolar , Epoprostenol/fisiologia , Feminino , Humanos , Lactente , Masculino , Tromboxano A2/fisiologia
7.
Chem Commun (Camb) ; 58(20): 3322-3325, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35179528

RESUMO

Two inorganic-organic hybrid isopolyoxoniobates (1 and 2) based on new high-nuclearity {Nb54O151} clusters have been synthesized under hydrothermal conditions. In particular, the combination of the unique {Nb54O151} clusters with copper-amine complexes has led to rare helical nanotubes, which are further linked by alkali metal cations or copper-amine complexes into two 2D similar bamboo-raft-like layered networks (1 and 2), respectively. Compound 1 exhibits effective base-catalytic decomposition of chemical warfare agent simulants dimethyl methylphosphonate (DMMP) and diethyl cyanophosphonate (DECP).

8.
Mol Cell Biochem ; 340(1-2): 7-14, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20157766

RESUMO

The Notch signaling pathway has been implicated in the development of several leukemia and lymphoma. In order to investigate the relationship between Notch signaling and acute myeloid leukemia (AML), in this study, we expressed a recombinant Notch ligand protein, the DSL domain of the human Jagged1 fused with GST (GST-Jag1). GST-Jag1 could activate Notch signaling in the human promyelocytic leukemia cell line HL60, as shown by a reporter assay and the induced expression of Notch effector gene Hes1 and Hes5. However, GST-Jag1 had no effect on the proliferation and survival of HL60 cells. HL60 cells expressed both Notch ligands and receptors, and had a potential of reciprocal stimulation of Notch signaling between cells. We, therefore, blocked Notch signaling in cultured HL60 cells using a gamma-secretase inhibitor (GSI). We found that GSI inhibited the proliferation of HL60 cells significantly by blocking the cell-cycle progression in the G1 phase. Furthermore, GSI induced remarkably apoptosis of HL60 cells. These changes in GSI-treated HL60 cells correlated with the down-regulation of c-Myc and Bcl2, and the low phosphorylation of the Rb protein. These results suggested that reciprocal Notch signaling might be necessary for the proliferation and survival of AML cells, possibly through the maintenance of the expression of c-Myc and Bcl2, as well as the phosphorylation of the Rb protein.


Assuntos
Proliferação de Células , Leucemia Promielocítica Aguda/metabolismo , Receptores Notch/metabolismo , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Secretases da Proteína Precursora do Amiloide/metabolismo , Apoptose , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Ciclo Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Células HL-60 , Células HeLa , Proteínas de Homeodomínio/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteína Jagged-1 , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/patologia , Proteínas de Membrana/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Repressoras/metabolismo , Proteínas Serrate-Jagged , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Fatores de Transcrição HES-1 , Transfecção
9.
Front Chem ; 8: 586009, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33392148

RESUMO

This study reported a series of cube-shaped polyoxoniobates, {MCu12O8)(Cu12XmOn)(Nb7(OH)O21)8} [M = Nb(1, 2), Ln3+(3), X = I(1, m = 3, n = 3; 2, m = 5, n = 1), Br(3, m = 5, n = 1)]. As the first octahedral Cu12XmOn cluster incorporated polyoxoniobate, the cube-shaped three-shell structure of {MCu12O8)(Cu12XmOn)(Nb7(OH)O21)8} polyanion contains a {MCu12O8} body-centered cuboctahedron, a {Cu12XmOn} octahedron and a {Cu12(Nb7(OH)O21)8} cube. Compounds 1, 2, 3 show effective catalytic activities for the hydrolytic decomposition of chemical warefare agent simulants.

10.
Chem Asian J ; 15(10): 1574-1579, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32222037

RESUMO

In this work, two rare high-dimensional polyoxoniobates with formulas of H9 [Cu(en)(H2 O)2 ][Cu(en)2 ]8 [Dy(H2 O)4 ]3 [Nb24 -O69 (H2 O)3 ]2 ⋅ 36H2 O (1) and H9 K[Cu(en)2 (H2 O)]5 [Cu(en)2 ]4 -[Eu(H2 O)4 ]3 [Nb24 O69 (H2 O)3 ]2 ⋅ 2en ⋅ 45H2 O (2) have been obtained under hydrothermal conditions. These extended materials are constructed from lanthanide-incorporated triangular-prism-like polyoxoniobate secondary building units (SBUs) {[Ln(H2 O)4 ]3 [Nb24 O69 (H2 O)3 ]2 } (Ln=Dy, Eu). 1 and 2 represent the first examples of high-dimensional polyoxometalate materials based on such lanthanide-incorporated triangular-prism-like polyoxoniobate SBUs. Furthermore, the proton conduction property and the luminescent emission of these materials were evaluated.

11.
Ying Yong Sheng Tai Xue Bao ; 27(12): 3905-3912, 2016 Dec.
Artigo em Zh | MEDLINE | ID: mdl-29704349

RESUMO

Huizhou-Styled Village is a typical representative of the traditional Chinese ancient villages. It preserves plentiful information of the regional culture and ecological connotation. The Huizhou-Style is the apotheosis of harmony between the Chinese ancient people and nature. The research and protection of Huizhou-Styled Village plays a very important role in fields of ecology, geography, architecture and esthetics. This paper took Chengkan Village of Anhui Province as an exa-mple, and proposed a new model of ideal ecosystem oriented in theories of Feng-shui and psychological field. The new method of characterizing 3D landscape index was introduced to explore the spatial patterns of Huizhou-Styled Village and the functionality of the composited landscape components in a quantitative way. The results indicated that, Chengkan Village showed a spatially composited pattern of "mountain-forest-village-river-forest". It formed an ideal settlement ring structure with human architecture in the center and natural landscape around in the horizontal and vertical horizons. The traditional method based on the projection distance caused the deviation of the landscape index, such as underestimating the area and distance of landscape patch. The 3D landscape index of average patch area was 6.7% higher than the 2D landscape index. The increasing rate ofarea proportion in 3D index was 1.0% higher than that of 2D index in forest lands. Area proportion of the other landscapes decreased, especially the artificial landscapes like construction and cropland landscapes. The area and perimeter metric were underestimated, whereas the shape metric and the diversity metric were overestimated. This caused the underestimation of the dominance of natural patches was underestimated and the overestimation of the dominance of artificial patches during the analysis of landscape pattern. The 3D landscape index showed that the natural elements and their combination in Chengkan Village ecosystem reflected better ecological function, the key elements and the composited landscape ecosystem preserved higher stability, connectivity and aggregation. The quantitative confirmation showed that the Huizhou-Styled Village represented by Chengkan Village is an ideal ecosystem.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Planejamento Ambiental , Arquitetura , China , Ecologia , Florestas , Geografia , Humanos , Rios , Análise Espacial
12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 19(6): 1415-8, 2011 Dec.
Artigo em Zh | MEDLINE | ID: mdl-22169294

RESUMO

The purpose of this study was to compare the efficacy of CEP plus G-CSF and CVP plus G-CSF regimens in the mobilization and collection of peripheral blood hematopoietic stem cells (PBHSC), and in the hematopoietic recovery. 57 patients with non-Hodgkin's lymphoma (NHL) underwent autologous PBHSC transplantation were analyzed retrospectively. The PBHSC were mobilized and collected by using CEP plus G-CSF and CVP plus G-CSF respectively, and were retransfused into these NHL patients after preconditioning, then the mobilization efficacy, adverse reactions and hematopoietic recovery were analyzed. The results showed that the WBC count decreased to ≤ 1.0 × 10(9)/L, platelet amount dropped to ≤ 40 × 10(9)/L during peripheral blood stem cell mobilization of all patients, which indicated successful collection of PBHSC. The mean value of (4.38 ± 3.40) × 10(8)/kg mononuclear cells (MNC) containing (2.79 ± 2.53) × 10(6)/kg CD34(+) cells were collected in CEP plus G-CSF group, while the mean value of (3.31 ± 1.23) × 10(8)/kg MNC containing (2.02 ± 0.87) × 10(6)/kg CD34(+) cells were collected in CVP plus G-CSF group. The efficacy of mobilization in CEP plus G-CSF group was significantly higher than that in CVP plus G-CSF group (p < 0.05). After preconditioning, bone marrow was suppressed in all patients. The average time of WBC count recovery to ≥ 1.0 × 10(9)/L was 11.4 days in CEP plus G-CSF group and 12.3 days in CVP plus G-CSF group; the average time of platelet amount recovery to ≥ 50 × 10(9)/L was 18.6 days in CEP plus G-CSF group and 19.3 days in CVP plus G-CSF group. The statistical analysis showed no significant difference in the average time of hematopoietic recovery between 2 groups. It is concluded that autologous PBHSC transplantation shows significant effect for treatment of patients with NHL. Either modified CEP or CVP plus G-CSF regimen is safe and effective in PBHSC mobilization. The CEP plus G-CSF regimen is better than CVP plus G-CSF regimen.


Assuntos
Mobilização de Células-Tronco Hematopoéticas/métodos , Linfoma não Hodgkin/terapia , Transplante de Células-Tronco de Sangue Periférico , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplante Autólogo , Adulto Jovem
13.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 24(5): 450-2, 2008 May.
Artigo em Zh | MEDLINE | ID: mdl-18466699

RESUMO

AIM: To construct a Pichia pastoris expression vector PIC- hDll1(ext)-Fc, and to express the fusion protein containing the extracellular domain of human Delta-like1 and the Fc fragment of human IgG1 fusion gene in Pichia pastoris. METHODS: The extracellular domain of human Delta-like1 gene was amplified from pEF-BOSneo-hdll1(ext)-Fc by PCR. The expression vector was constructed by DNA recombination. The constructed plasmid was transformed into yeast GS115 by electroporation. The recombinant transformants with a high copy number of the plasmid were selected by using MD plate and G418. The expression of protein was induced by addition of methanol.Then analyzed protein expression by SDS-PAGE and Western blot. RESULTS: The extracellular domain of human Delta-like1 gene was effectively amplified. The DNA sequencing result showed that the constructed plasmid containing hDll(ext)-Fc fusion gene was the same as designed. The fusion protein was successfully expressed in Pichia pastoris. CONCLUSION: The hDll1(ext) gene has been successfully cloned and expressed in the form of Fc fusion protein, which provides a new fusion protein for further experiments.


Assuntos
Fragmentos Fc das Imunoglobulinas/metabolismo , Pichia/genética , Proteínas Recombinantes/farmacologia , Eletroporação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Vetores Genéticos/genética , Humanos , Fragmentos Fc das Imunoglobulinas/genética , Imunoglobulina G/genética , Imunoglobulina G/metabolismo , Metanol/química , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Proteínas Recombinantes de Fusão
14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 16(4): 910-4, 2008 Aug.
Artigo em Zh | MEDLINE | ID: mdl-18718088

RESUMO

In order to construct a pichia pastoris expression vector containing the extracellular domain of human Jagged1 and the Fc fragment of human IgG1 fusion gene, or containing only the Fc fragment of human IgG1 and to express them in pichia pastoris. The extracellular domain of human Jagged1 gene was cloned from normal human bone marrow cells. After DNA sequencing, the extracellular domain of Jagged1 gene was inserted into pIC-Fc vector constructed previously, which is Pichia pastoris expression vector containing only the Fc fragment of human IgG1. The constructed plasmid was transformed into yeast GS115 by means of electroporation. The recombinant transformants with a high copy number of the plasmid were selected on MD plate with G418. The expression of protein was induced by addition of methanol. Then, protein expression was analyzed by SDS-PAGE. The results indicated that the extracellular domain of human Jagged1 gene was effectively amplified. The DNA sequencing result showed that the constructed plasmid containing hJagged1(ext)-Fc fusion gene was the same as designed. The fusion protein was successfully expressed in Pichia pastoris. It is concluded that the hJagged1(ext) gene has been successfully cloned and expressed, which provides a new fusion protein for further experiments, the hJagged1(ext)-Fc fusion protein can be used as a new stimulator for proliferation of hematopoietic stem/progenitor cells in vitro.


Assuntos
Proteínas de Ligação ao Cálcio/biossíntese , Vetores Genéticos/genética , Fragmentos Fc das Imunoglobulinas/biossíntese , Imunoglobulina G/biossíntese , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Proteínas de Membrana/biossíntese , Pichia/metabolismo , Proteínas de Ligação ao Cálcio/genética , Humanos , Fragmentos Fc das Imunoglobulinas/genética , Imunoglobulina G/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteína Jagged-1 , Proteínas de Membrana/genética , Pichia/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Serrate-Jagged , Transfecção
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