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1.
J Nanosci Nanotechnol ; 18(3): 1847-1850, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448670

RESUMO

The surface activated bonding (SAB) method generally has the advantage of high bonding strength, low contact resistance, and high microstructural stability at room temperature. In this study, Ti-Al laminates were produced by surface activated bonding with aluminum and titanium foils. Heat treatment was conducted at the temperature range from 200 to 550 °C in vacuum. The bonding strength Ti-Al laminates was measured by a peel test, and the interfacial characteristics were investigated microstructural observation. The results showed that the bonding strength was the highest with heat treatment at 400 °C, microstructure observation revealed that the bonding strength of the Ti-Al laminate was influenced by the interfacial characteristics.

2.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 2): m122-3, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23424413

RESUMO

In the title compound, [Ca(C(19)H(11)F(2)O(2))(2)(CH(3)OH)(4)]·4CH(3)OH, the Ca(2+) ion is located on an inversion centre and is hexa-coordinated by two O atoms of two 4,4''-difluoro-1,1':3',1''-terphenyl-2'-carboxyl-ate ligands and four O atoms of four methanol ligands, forming a CaO(6) polyhedron with a slightly distorted octa-hedral coordination geometry. The Ca-O-C angle between the carboxyl-ate group and the calcium ion is 171.8 (2)°. Two types of inter-molecular hydrogen-bond inter-actions (C=O⋯H and O-H⋯O) between the carboxyl-ate ligand, the methanol solvent mol-ecules and the coordinating methanol ligands generate a two-dimensional network parallel to (001).

3.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): m1264-5, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125592

RESUMO

The structure of the title compound, [Co(2)(C(19)H(11)F(2)O(2))(4)(C(5)H(5)N)(2)(H(2)O)(2)]·2C(4)H(10)O, comprises two Co(II) atoms in a distorted square pyramidal coordination environment, straddling a crystallographic inversion center with a Co⋯Co separation of 3.1923 (15) Å. Each Co(2+) cation is coordinated by three O atoms of three 4,4''-difluoro-1,1':3',1''-terphenyl-2'-carboxyl-ate ligands, one water O atom and one pyridine N atom, forming a CoO(4)N polyhedron. Strong intra-molecular O-H⋯O hydrogen bonds are observed between terminal metal-bound carboxyl-ate groups and water O atoms.

4.
Materials (Basel) ; 14(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203845

RESUMO

In this work, the microstructure and corrosion behavior of a novel Al-6Mg alloy were investigated. The alloy was prepared by casting from pure Al and Mg+Al2Ca master alloy. The ingots were homogenized at 420 °C for 8 h, hot-extruded and cold-rolled with 20% reduction (CR20 alloy) and 50% reduction (CR50 alloy). The CR50 alloy exhibited a higher value of intergranular misorientation due to a higher cold rolling reduction ratio. The average grain sizes were 19 ± 7 µm and 17 ± 9 µm for the CR20 and CR50 alloys, respectively. An intergranular corrosion (IGC) behavior was investigated after sensitization by a nitric acid mass-loss test (ASTM G67). The mass losses of both the CR20 and CR50 alloys were similar at early periods of sensitization, however, the CR20 alloy became more susceptible to IGC as the sensitization time increased. Grain size and ß phase precipitation were two critical factors influencing the IGC behavior of this alloy system.

5.
Arch Pharm Res ; 31(11): 1399-404, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19023535

RESUMO

Methanol extracts of the root of Dipsacus asper Wall (Dipsacaceae) were found to exhibit apoptosis-inducing activities in U937 (human monocyte-like histiocytic) cells. Investigation of the active n-BuOH fraction led to the isolation of akebia saponin D (ASD). Structure was established by spectroscopic methods. Treatment of U937 cells with ASD induced apoptosis in a dose dependent manner. ASD exerted strong cytotoxicity against human and murine leukemia cells. It is significantly increased the subG1 cell population and expression of p53 and Bax gene. And also ASD enhanced NO production from RAW264.7 macrophage cells. Taken together, these results strongly indicate that ASD may exert apoptosis-inducing activity via induction of apoptosis through activation chiefly via the nitric oxide and apoptosis-related p53 and Bax gene expression. These data provide scientific evidence that Dipsacus asper Wall can be useful as a chemopreventive agent.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Dipsacaceae/química , Saponinas/farmacologia , Antibióticos Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Expressão Gênica/efeitos dos fármacos , Genes p53/efeitos dos fármacos , Humanos , Modelos Moleculares , Conformação Molecular , Óxido Nítrico/biossíntese , Óxido Nítrico/fisiologia , Raízes de Plantas/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saponinas/isolamento & purificação , Células U937 , Proteína X Associada a bcl-2/genética
6.
Dalton Trans ; 45(4): 1727-36, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26698631

RESUMO

Using the sterically hindered terphenyl-based carboxylate, the tetrameric Co(ii) complex [Co4(µ3-OH)4(µ-O2CAr(4F-Ph))2(µ-OTf)2(Py)4] () with an asymmetric cubane-type core has been synthesized and fully characterized by X-ray diffraction, UV-vis spectroscopy, and electron paramagnetic resonance spectroscopy. Interestingly, the cubane-type cobalt cluster with 3-chloroperoxybenzoic acid as the oxidant was found to be very effective in the epoxidation of a variety of olefins, including terminal olefins which are more challenging targeting substrates. Moreover, this catalytic system showed a fast reaction rate and high epoxide yields under mild conditions. Based on product analysis and Hammett studies, the use of peroxyphenylacetic acid as a mechanistic probe, H2(18)O-exchange experiments, and EPR studies, it has been proposed that multiple reactive cobalt-oxo species Co(V)[double bond, length as m-dash]O and Co(IV)[double bond, length as m-dash]O were involved in the olefin epoxidation.

7.
Chem Asian J ; 8(6): 1152-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23509044

RESUMO

Using two kinds of carboxylate ligands with small but significant differences in steric size, symmetric and asymmetric Fe(II) and Ni(II) cubanes have been synthesized in a controlled fashion. Fast sweeping pulsed field measurements showed magnetization hysteresis loops for two cubane-type molecular complexes, [Ni4(µ-OMe)4(O2CAr(4F-Ph))4(HOMe)8] and [Ni4(µ-OMe)4(O2CAr(Tol))4(HOMe)6], thus suggesting single-molecule magnet behavior. To differentiate the magnetic properties between the symmetric and asymmetric cubanes, detailed electron paramagnetic resonance (EPR) measurements were performed. From the EPR data, taken at various frequencies and temperatures, zero-field splitting parameters D, E, and other higher-order parameters for both cubane samples were extracted. Compared to the symmetric Ni-cubane, the asymmetric one shows an increase in the D and E values by about 20%, thereby suggesting structural engineering effects on the magnetic properties. By using the magnetic parameters determined by EPR, a static magnetization curve at 2 K and a temperature dependence of the magnetic susceptibility were simulated. A good agreement between theoretical and experimental data confirms the validity of the values obtained from EPR measurements.

8.
Cyberpsychol Behav Soc Netw ; 14(11): 665-72, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21595524

RESUMO

The objective of this article is to fully understand Internet addiction, we aimed to compare the attachment styles and psychopathologies associated with problematic Internet use with those related to alcohol use. Through the participation of 141 male participants, the present study assessed problematic Internet and alcohol use, attachment, psychopathology, and demographic data via the use of self-rating questionnaires. We explored the significant predictors among avoidant and anxious attachments, depression, anxiety, and phobia to explain problematic Internet and alcohol use. The results showed that anxious attachment, depression, and anxiety could explain problematic alcohol use. In contrast, both anxious and avoidant attachment as well as depression and phobia explained problematic Internet use. Additionally, depression moderated the effects of avoidant attachment on problematic Internet use. We demonstrated that the interaction of attachment and psychopathology predicts problematic Internet use originating from an earlier stage of life than that associated with problematic alcohol use.


Assuntos
Transtornos Relacionados ao Uso de Álcool/psicologia , Comportamento Aditivo/psicologia , Internet/estatística & dados numéricos , Transtornos Mentais/psicologia , Apego ao Objeto , Adulto , Fatores Etários , Transtornos Relacionados ao Uso de Álcool/complicações , Comportamento Aditivo/complicações , Humanos , Masculino , Transtornos Mentais/complicações , Pessoa de Meia-Idade , República da Coreia , Estatísticas não Paramétricas , Adulto Jovem
9.
J Med Food ; 14(3): 240-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21332403

RESUMO

In the present study, we investigated the effects of gallic acid (GA) (3,4,5-trihydroxybenzoic acid), a polyhydroxyphenolic compound, isolated from Rhus chinensis, on the human monocytic lymphoma cell line U937. In vitro experiments showed that treating U937 cells with various amounts of GA inhibited cell viability and induced apoptosis in a dose-dependent manner. In order to understand the mechanism by which GA induces apoptosis, we examined the gene expression of p53, nuclear factor κB (NF-κB), and inhibitor of NF-κB (I-κB) after treating the cells with GA and found that expression levels of the genes for p53 and NF-κB increased and that for I-κB decreased. The results obtained from western blotting with U937 cells showed up-regulation of NF-κB protein and down-regulation of proliferating cell nuclear antigen and I-κB protein. These results demonstrate that GA efficiently induces apoptosis in U937 cells and that GA is a potential chemotherapeutic agent against lymphoma.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Ácido Gálico/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacos , Linfoma/tratamento farmacológico , Monócitos/efeitos dos fármacos , Fitoterapia , Rhus/química , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ácido Gálico/farmacologia , Humanos , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Linfoma/genética , Linfoma/metabolismo , Monócitos/fisiologia , NF-kappa B/genética , NF-kappa B/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Células U937
10.
Arch Pharm Res ; 33(4): 545-50, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20422363

RESUMO

Three compounds were isolated from the ethyl acetate soluble fraction of the methanolic extract of the leaves of Catalpa ovata (Bignoniaceae) through repeated column chromatography. We investigated the effects of these compounds on T cell-mediated responses for tumor surveillance and proliferation in U937, HL60, and Molt-4 leukemia cells. Compounds 1-3 inhibited proliferation of those cells in a dose-dependent manner. Compound 3 showed mild effect in Molt-4 cell cytotoxicity. Compound 3 enhanced gene expressions of p53 and IL-4, but decreased IL-2 and IFN-Gamma genes in Molt-4 cell. Our findings indicate that compound 3 may enhance T cell-mediated immune responses and anticancer properties.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Bignoniaceae/química , Imunidade Celular/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Linfócitos T/efeitos dos fármacos , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Apoptose/genética , Apoptose/imunologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/biossíntese , Citocinas/imunologia , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Imunidade Celular/imunologia , Medicina Tradicional Coreana , Estrutura Molecular , Folhas de Planta/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/imunologia , Células U937
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