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The current study replicated Wang and Singer's ([2021]. A cross-cultural study of self-defining memories in Chinese and American college students. Frontiers in Psychology, 11. ) finding that Chinese college students from the People's Republic of China (PRC) recalled more self-defining memories (SDMs) focused on high school academic stress than their American counterparts. Seventy-eight American students from a private 4-year liberal arts college and 96 Chinese students from 13 different Chinese universities recalled two SDMs and rated them for affect, recall frequency, and importance. Once again, Chinese college students were more likely than American students to recall academic stress SDMs, but also expressed more redemptive themes in these memories. Overall, Chinese students rated their SDMs as more positive than the Americans, while the American sample tended to recall their negative memories more frequently. Contrasting the SDMs, American students self-reported higher levels of stress about their high school workload and less academic self-confidence. Regressions linked more negative affect in American SDMs to these work load and self-confidence concerns. Chinese students' SDM negative affect was most strongly predicted by perceived academic stress linked to parental and teachers' expectations. The discussion highlights the potential influence of Confucian values in the Chinese students' responses to past academic stress and their internalisation of academic stress memories in their narrative identity. [ABSTRACT FROM AUTHOR]

In this paper, the unsolvability of inverse singular value problems almost everywhere is discussed. Applying the method described by Sun and Ye [J Comput Math. 1986;4:212-226], a sufficient condition is given such that the inverse singular value problems are unsolvable almost everywhere. This result shows that inverse singular value problems are unsolvable almost everywhere if the multiplicity of zero singular values is sufficiently large. [ABSTRACT FROM AUTHOR]

Two new oxidovanadium(V) complexes with the general formula [VOL(bha)], where L represents the deprotonated hydrazone ligands 2-hydroxy-N'-(4-methoxybenzylidene)naphthohydrazide (H2L1) for1andN'-(2-chlorobenzylidene)-2-hydroxynaphthohydrazide (H2L2) for2, and bha represents the monoanionic form of benzohydroxamic acid (Hbha), have been prepared and characterized by elemental analysis, infrared and UV-Vis spectra, and thermal behavior. Structures of the complexes have been further determined by single-crystal X-ray diffraction. The V atoms in the complexes are coordinated by the three donor atoms of the hydrazone ligands, the oxygen atoms of the benzohydroxamate ligands, and oxido oxygen atoms, constituting octahedral coordination spheres. [ABSTRACT FROM AUTHOR]

A new oxovanadium(V) complex, [N'-(3-ethoxy-2-hydroxybenzylidene)-4-fluorobenzohydrazido](quinolin-8-olato)oxovanadium(V), [VO(EFH)(QN)], where EFH is the anion ofN'-(3-ethoxy-2-hydroxybenzylidene)-4-fluorobenzohydrazide, and QN is the anion of 8-hydroxyquinoline, was prepared and characterized by elemental analysis, infrared spectra, thermal analysis and single-crystal X-ray diffraction. The complex crystallizes in the monoclinic space groupP21/n, with unit cell dimensionsa= 8.3921(4) Å,b= 28.200(1) Å,c= 10.0237(5) Å, β = 102.394(1)°,V= 2316.9(2) Å3,Z= 4, GOOF = 1.101,R1= 0.0464, andwR2= 0.1081. The V atom is coordinated by the three donor atoms of EFH and two donor atoms of QN, as well as one oxo oxygen group, forming an octahedral coordination. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the association between basal serum testosterone levels andin vitrofertilization (IVF) parameters in cycling women. A retrospective cohort study was performed at a clinical IVF center, and 495 women with regular menstruation were enrolled. Serum testosterone levels were measured before the start of IVF treatment cycle. We found that basal serum testosterone levels were negatively associated with female age and FSH/LH ratios. In contrast, we found a positive correlation between serum testosterone levels and the number of oocytes and available embryos. However, there was no significant association between testosterone levels and pregnancy outcome. Our results suggest that basal serum testosterone levels were significantly related to certain classic indicators of ovarian reserve, such as age and FSH/LH ratios. Increased testosterone levels improved ovarian response in cycling women, but they fail to predict pregnancy and miscarriage rate. [ABSTRACT FROM AUTHOR]

A new copper(II) complex, [Cu(AA)(EDA)2] (1), and a new zinc(II) complex, [Zn(PA)2(EDA)] (2), where AA is 1-naphthylacetate, PA is 4-nitrophenylacetate, and EDA isN,N-dimethylethane-1,2-diamine, have been prepared and characterized. Structures of the complexes have been characterized by single-crystal X-ray diffraction. Complex1crystallizes as monoclinic space groupP21/n, with unit cell dimensionsa= 7.3327(4) Å,b= 24.031(1) Å,c= 13.9031(7) Å, β = 91.803(2)°, V = 2448.7(2) Å3, Z = 4,R1= 0.0487,wR2= 0.1199, S = 1.053. Complex2crystallizes as monoclinic space groupP21/c, with unit cell dimensionsa= 24.693(4) Å,b= 12.023(2) Å,c= 7.524(1) Å, β = 89.95(3)°, V = 2233.8(6) Å3, Z = 4,R1= 0.0696,wR2= 0.1845, S = 0.999. Complex1is a mononuclear copper(II) species, with the Cu atom coordinated in a square pyramidal geometry. Complex2is a mononuclear zinc complex, with the Zn atom coordinated in a tetrahedral geometry. Single crystals of the complexes are stabilized by hydrogen bonds and π…π interactions. [ABSTRACT FROM AUTHOR]

A new dinuclear bromido-coordinated Schiff base zinc(II) complex, [Zn2Br2L1(MeOH)]·MeOH (1), and a new mononuclear bromido-coordinated Schiff base zinc(II) complex, [ZnBr2L2] (2), where L1is the dianionic form ofN,N’-bis(5-fluoro-2-hydroxybenzylidene)propane-1,3-diamine (H2L1), and L2is the zwitterionic form of 2-[(3-dimethylammoniopropylimino)methyl]-4-fluorophenol, have been preprared and characterized mainly by single-crystal X-ray diffraction. Complex 1 crystallizes in the monoclinic space groupP21/nwith unit cell dimensionsa= 10.0876(9) Å,b= 8.9549(8) Å,c= 26.586(2) Å, β = 95.134(2)º, V = 2391.9(4) Ǻ3, Z = 4,R1= 0.0547, andwR2= 0.1025. Complex 2 crystallizes in the monoclinic space groupP21/cwith unit cell dimensionsa= 7.359(1) Å,b= 13.798(2) Å,c= 17.676(2) Å, β = 114.602(2)º, V = 1631.8(4) Ǻ3, Z = 4,R1= 0.0877, andwR2= 0.2197. The inner Zn atom in 1 is five-coordinated in a square pyramidal geometry. The outer Zn atom in 1 and the Zn atom in 2 are four-coordinated in tetrahedral geometry. The crystals of the complexes are stabilized by intermolecular hydrogen bonds. [ABSTRACT FROM PUBLISHER]

In this paper, the backward error of periodic invariant subspaces for regular periodic pairs is defined and its explicit expression is derived. In particular, we also present the expression of the backward error of generalized invariant subspaces for the regular matrix pair. The results are illustrated by two numerical examples. [ABSTRACT FROM AUTHOR]

A μ-oxido-bridged dinuclear iron(III) complex, [Fe2O(L1)2(L2)2], where L1and L2are the deprotonated forms of 2,4-dichloro-6-[(2-morpholin-4-ylethylimino)methyl]phenol and 3,5-dichlorosalicylaldehyde, respectively, has been prepared and characterized by elemental analysis, infrared spectrum, and single-crystal X-ray determination. The complex crystallizes in the triclinic space groupP, with unit cell dimensionsa= 10.670(1) Å,b= 11.585(1) Å,c= 19.748(2) Å, α = 86.766(2)°, β = 85.038(2)°, γ = 73.973(2)°,V= 2336.1(4) Å3,Z= 2, GOOF = 1.019,R1= 0.0422, andwR2= 0.1024. Structural analysis shows that the iron atoms in the complex are hexacoordinate with a normal Fe-O-Fe bridging angle of 150.84(13)°. Each Fe atom is coordinated by the NNO donor atoms of L1, OO donor atoms of L2, and one bridging O atom. The Fe· · ·Fe distance is 3.467(2) Å. [ABSTRACT FROM PUBLISHER]

The financial crises of 1997–98 and 2008–09 each had a debilitating effect on Southeast Asian market economies because of the dominance of exports and foreign ownership. However, the 1997–98 financial crisis positively impacted electronics exports, production and employment, due to a booming US economy. The contraction in demand in the US during the 2008–09 crisis reduced electronics exports from Southeast Asia with the exceptions of Indonesia and the Philippines, which were shielded by regional linkages with Singapore, Malaysia and China. Foreign labour repatriation and fiscal stimulus packages helped Malaysia and Thailand rebound quickly from the 2008–09 crisis. In the Philippines, the 2008–09 crisis expanded further the casualisation of labour as retrenched workers from Malaysia and Singapore returned home. State grants encouraged upgrading in Singapore and to some extent in Malaysia, but the liberal approach of Indonesia, the Philippines and Thailand limited them to low-value-added activities. However, Singapore’s and Malaysia’s transnational-based strategy failed to reproduce the technological leapfrogging experience of South Korea and Taiwan. Also, Malaysia’s ethno-patronage policies discouraged upgrading in national firms. [ABSTRACT FROM PUBLISHER]

Two new mononuclear Schiff base nickel(II) complexes, [Ni(ClSal)] (1) and [Ni(MeSal)] (2) (H2ClSal =N,N′-bis(3,5-dichlorosalicylidene)-1,3-pentanediamine; H2MeSal =N,N′-bis(3-methylsalicylidene)-1,2-ethanediamine), have been synthesized and characterized by elemental analyses, infrared spectra, and single-crystal X-ray diffraction. Complex 1 crystallizes in the orthorhombic space groupP212121, with unit cell dimensionsa= 9.788(1) Å,b= 10.206(1) Å,c= 20.458(2) Å,V= 2043.7(4) Å3,Z= 4,R1= 0.0814, andwR2= 0.1689. Complex 2 crystallizes in the monoclinic space groupP21/n, with unit cell dimensionsa= 11.6353(5) Å,b= 11.8807(6) Å,c= 12.8241(6) Å,β= 115.213(1)°,V= 1603.9(1) Å3,Z= 4,R1= 0.0243, andwR2= 0.0675. The Ni atoms in the complexes are four-coordinated in square planar geometry by the N2O2donor set of the ligands. [ABSTRACT FROM AUTHOR]

A pair of mononuclear Schiff base zinc(II) complexes, [ZnLCl2] (1) and [ZnLBr2] (2), have been prepared by the reaction of equimolar quantities of a new Schiff base ligand 2-[(2-dimethylammonioethylimino)methyl]-4-methylphenolate with ZnCl2and ZnBr2, respectively, in methanol. The structures of the complexes have been characterized by single-crystal X-ray diffraction. Complex 1 crystallizes as orthorhombic space groupP212121, with unit cell dimensionsa= 7.518(1) Å,b= 13.518(2) Å,c= 14.766(2) Å, V = 1500.7(3) Å3, Z = 4,R1= 0.0301,wR2= 0.0780, S = 1.028. Complex 2 crystallizes as orthorhombic space groupP212121, with unit cell dimensionsa= 7.731(1) Å,b= 13.761(1) Å,c= 14.705(1) Å, V = 1564.4(1) Å3, Z = 4,R1= 0.0230,wR2= 0.0488, S = 1.031. The Zn atom in each of the complexes is four-coordinated in a tetrahedral geometry by the phenolate O and imine N atoms of the Schiff base ligand, and two halide anions. Single crystals of the complexes are stabilized by hydrogen bonds. [ABSTRACT FROM AUTHOR]

New sensor technologies (e.g. surveillance cameras, loop detectors) enable the synthesis of disaggregated vehicle information from multiple locations. This article studies the camera location problem for traffic surveillance in urban road networks with multiple user classes. All users are differentiated by their own acceptance degree of camera monitoring and make their route choices in a logit-based stochastic user equilibrium manner. A bi-level programming model is proposed to formulate the problem and solved by the sensitivity analysis based branch and bound method. Numerical examples are presented to illustrate the model application and show the effectiveness of the solution method. [ABSTRACT FROM AUTHOR]

A new mononuclear Schiff base cobalt(III) complex, [Co(MEA) (N3)(DMF)] (1), and a new mononuclear Schiff base manganese(III) complex, [Mn(EEA)(N3)(OH2)] (2) (MEA is bis (5-methoxysalicylidene)ethylenediamine; EEA is bis(6-ethoxys alicylidene)ethylenediamine), have been prepared and structurally characterized by physicochemical and single-cyrstal X-ray diffraction. Complex 1 crystallizes in the monoclinic space groupP21/cwith unit cell dimensionsa= 9.910(1) Å,b= 19.279(1) Å,c= 12.410(1) Å,β= 102.729(2)°, V = 2312.8(2) Å3, Z = 4,R1= 0.0319, andwR2= 0.0779. Complex 2 crystallizes in the monoclinic space groupP21/cwith unit cell dimensionsa= 14.252(2) Å,b= 22.227(3) Å,c= 13.613(2) Å,β= 91.512(2)°, V = 4310.7(11) Å3, Z = 8,R1= 0.0392, andwR2= 0.0839. The metal atom in each complex is in an octahedral coordination. Crystal of complex 2 was stabilized by hydrogen bonds. [ABSTRACT FROM PUBLISHER]

The involvement of oxidized proteins to the development of biological diseases has been studied for a few decades, but the effects and the mechanisms of protein oxidation in food systems are largely unknown. Protein oxidation is defined as the covalent modification of a protein induced either by the direct reactions with reactive oxygen species (ROS) or indirect reactions with secondary by-products of oxidative stress. ROS can cause oxidation in both amino acid side chains and protein backbones, resulting in protein fragmentation or protein–protein cross-linkages. Although all amino acids can be modified by ROS, cysteine, and methionine that are the most susceptible to oxidative changes due to high reaction susceptibility of the sulfur group in those amino acids. Oxidative modifications of proteins can change their physical and chemical properties, including conformation, structure, solubility, susceptibility to proteolysis, and enzyme activities. These modifications can be involved in the regulation of fresh meat quality and influence the processing properties of meat products. Oxidative stress occurs when the formation of oxidants exceeds the ability of antioxidant systems to remove the ROS in organisms. Increased levels of protein oxidation have been associated with various biological consequences, including diseases and aging, in humans and other animal species. The basic principles and products of protein oxidation and the implications of protein oxidation in food systems, especially in meat, are discussed in this review. [ABSTRACT FROM AUTHOR]

Matrine is an alkaloid isolated from the medicinal plant Sophora flavescens Ait (Leguminosae) with various pharmacological and physiological effects. Here, we investigate its combined effects with imatinib, a specific tyrosine kinase inhibitor used clinically against leukemia cells, on bcr/abl-positive leukemia K562 cells. The results indicate that matrine enhanced imatinib-induced apoptosis in K562 cells through downregulation of protein levels of bcr/abl and phospho-Erk1/2. [ABSTRACT FROM AUTHOR]

Matrine is an alkaloid obtained primarily from roots of Sophora flavescens Ait. (Leguminosae), an herb used in traditional Chinese medicine to treat a range of disease. So far, the underlying molecular mechanism for the therapeutic effects of matrine has been poorly understood. In this work, we investigated the effects of matrine on tyrosine protein phosphorylation in human cells through immunoblotting. In bcr/abl-positive K562 cells, tyrosine phosphorylations of several proteins are altered in both time-and dose-dependent manners. Such alternations are distinct from those induced by the bcr/abl-targeting inhibitor STI571 and can be blocked by the later. The treatment of bcr/abl-negative lymphocytic and myeloid cell lines by matrine produced different patterns. In Raji cells, the tyrosine phosphorylation was the only protein affected. In U937 cells, no changes were observed. The findings in this work protein the first piece of evidence that matrine can alter the cellular signal transduction network at a molecular level. The observed changes in tyrosine phosphorylation of specific proteins provide important clues for uncovering the molecular mechanism of the therapeutic effects of matrine. [ABSTRACT FROM AUTHOR]

Malignant pleural effusion (MPE) is a functional 'cold' tumor microenvironment in which the antitumor activity of CD8+ T cells and natural killer T (NKT)-like cells is suppressed and the function of regulatory T (Treg) cells is enhanced. Using flow cytometry and immunofluorescence staining, we detected a distinct subset of NKT-like cells expressing FOXP3 in MPE. Through single-cell RNA sequencing (scRNA-seq) analysis, we found that the glycolysis pathway and pyruvate metabolism were highly activated in FOXP3+ NKT-like cells. Similar to Treg cells, FOXP3+ NKT-like cells highly expressed monocarboxylate transporter 1 (MCT1) and lactate dehydrogenase B to uptake and utilize lactate, thereby maintaining their immunosuppressive function and hyperlactylation in MPE. Furthermore, we found that MCT1 small molecule inhibitor 7ACC2 significantly reduced FOXP3 expression and histone lactylation levels in NKT-like cells in vitro. In conclusion, we reveal for the first time the altered phenotypic and metabolic features of FOXP3+ NKT-like cells in human MPE. [ABSTRACT FROM AUTHOR]

Cynomorium songaricum Rupr. (CSR), an edible and medicinal material, is widely cultivated in desert regions of Eastern and Western Asia, Europe, and North Africa. Ten glycoside constituents 1–10 including one new songaricumone A (1) were isolated from the fresh C. songaricum. Their structures were elucidated by comprehensive NMR data analysis. Further, various antioxidant effects of isolated compounds (1–3 and 5–10) were comprehensively and comparatively investigated. In conclusion, it is obvious that different glycosides vary significantly toward different sources of free radicals, which are attributed to different aglycones and substituted positions of sugar unit in structures. [ABSTRACT FROM AUTHOR]

A sensor was proposed and experimentally demonstrated to improve temperature and pressure sensitivity by the Vernier effect. The sensor is composed of a cascaded Fabry-Perot interferometer (FPI) and a Sagnac interferometer (SI), which has almost the same free spectral range (FSR) forming the Vernier effect. The SI is a fiber-loop consisting of a segment of polarization maintaining fiber (PMF). The FPI consists of a section of quartz capillary inserted between two sections of single mode fiber. A micro-channel is drilled in the quartz capillary using a femtosecond laser to circulate air inside and outside the Fabry-Perot (F-P) cavity. SI and FPI in the sensor structure are selectively sensitive to temperature and pressure. In temperature sensing, the SI acts as the sensor and FPI as the reference, whereas in pressure measurements, the FPI is the sensing unit and SI the reference unit. Thus, in Vernier effect sensing, they perform the functions of reference or sensing units to each other. The sensor provides high sensitivity for both temperature and pressure. Experimental results show that the temperature sensitivity is ∼23.14 nm/°C, which is ∼13.4 times higher for the single SI sensor (–1.73 nm/°C), and the pressure sensitivity is ∼49.2 nm/MPa, which is ∼12.2 times higher than for the single FPI sensor (4.02 nm/MPa). The sensor has a simple structure, easy preparation, and high sensitivity of both temperature and gas pressure, and has widespread prospective application. [ABSTRACT FROM AUTHOR]

A new azido-bridged polymeric copper(II) complex, [CuL(μ1,3-N3)]n·2nH2O (1), and a new thiocyanato-bridged polymeric copper(II) complex, [CuL(μ1,3-NCS)]n(2) (L = 4-methoxy-2-[(2-morpholin-4-ylethylimino)methyl]phenolate), have been prepared and structurally characterized by elemental analysis, IR spectra, and single-crystal X-ray determination. Each Cu atom in the complexes is coordinated by three donor atoms of Schiff bases and by two atoms of the pseudohalide ligands, forming a square pyramidal geometry. Azide and thiocyanate anions are preferred bridging groups for the construction of polymeric copper complexes with Schiff bases. [ABSTRACT FROM AUTHOR]

A novel bromido- and azido-bridged dinuclear copper(II) complex, [Cu2Br2L2]·[Cu2Br(N3)L2]·H2O, where L is the deprotonated form of the Schiff base 4-chloro-2-[(2-hydroxyethylimino)methyl]phenol, has been prepared and structurally characterized by elemental analysis, IR spectra, and single crystal X-ray crystallography. Each Cu atom in the complex is coordinated by three donor atoms of Schiff base ligand and by two bridging atoms, forming a square pyramidal geometry. The bromide and azide ligands are preferred bridging groups for the construction of dinuclear copper complexes with Schiff bases. [ABSTRACT FROM AUTHOR]

This study aimed to use different dose verification methods Treatment Planning System (TPS), thimble ionization chamber and two-dimensional matrix ionization chamber (MatriXX) to explore the compensating effects of several materials on high-energy electron beam irradiation. In this study, we positioned plexiglass panels, wet medical gauze, colloidal compensatory material and Vaseline compensator, all of the same thickness, flat on the surface of a MatriXX. The above four materials were placed on the surface of a thimble ionization chamber and irradiated with a linear accelerator. Under the same irradiation parameters, the compensation dose of of the tested materials was worked out by a dosimeter, which was connected at the thimble ionization chamber. Under vertical irradiation from the linear accelerator, the accelerator used the same irradiation conditions for the four materials, which were flat on the surface of the MatriXX, then determined the distribution of compensation doses by the soft system matching with the MatriXX. The results showed that the compensation dose of moist medical gauze was lower than the other three materials, the compensation dose of Plexiglass plate, colloidal compensatory material and vaseline compensation were approximate. The dose compensation effect of the vaseline compensation material made by our research group was close to the plexiglass plate and colloidal compensatory material used in radiotherapy in real life. Its physical and chemical properties are stable, easy to manufacture and store, and economical and practical. [ABSTRACT FROM AUTHOR]

Three new oxidovanadium(V) complexes, [VOLL′] (L = 2-chloro-N′-(3-ethoxy-2hydroxybenzylidene)benzohydrazide, L′ = acetohydroxamate for1, methylmaltolate for2, and ethylmaltolate for3), have been prepared. The complexes have been characterized by physicochemical methods and single-crystal X-ray determination. Vanadium in each complex is coordinated by the NOO donor set of L, the OO donor set of L′, and one oxido, forming octahedral coordination. The complexes were administered intragastrically to both normal and alloxan-diabetic mice for two weeks. The biological activities show that the complexes at doses of 10.0 and 20.0 mg V·kg−1can significantly decrease the blood glucose level in alloxan-diabetic mice, but the blood glucose level in the treated normal mice was not altered. [ABSTRACT FROM AUTHOR]

New oxidovanadium(V) complexes, [VOL1(bzh))]·H2O (1) and [VOL2(bzh))] (2), were prepared by the reaction of [VO(acac)2] (where acac?=?acetylacetonate) and benzohydroxamic acid (Hbzh) withN?-(5-bromo-2-hydroxybenzylidene)-3-methylbenzohydrazide (H2L1) andN?-(5-bromo-2-hydroxybenzylidene)-4-methylbenzohydrazide (H2L2), respectively, in methanol. Structures of the complexes were determined by elemental analysis, infrared and UV–vis spectra. Single crystal structures of the complexes were determined by X-ray diffraction. Vanadiums have octahedral coordination. Thermal stability and the inhibition of urease of the complexes were studied. [ABSTRACT FROM PUBLISHER]

Three Cu(II) complexes, [CuII2(L1)4(L2)2] (1), [CuII2(L1)4(H2O)2]·HL (2), and [CuII2(L1)3(L3)2]ClO4(3), with a ligand derived from protocatechuic acid (HL1 = C9H8O4=2,3-dihydrobenzo[b][1,4]dioxine-6-carboxylic acid, L2 = C7H9N=o-toluidine, L3 = C6H16N2=N,N-diethylethylenediamine) were synthesized and characterized by C, H, and N elemental analysis and single-crystal X-ray diffraction, which revealed that the three complexes have similar binuclear structures. Complexes1and3crystallized in triclinic space groupP-1and2in orthorhombic space groupP212121. The urease inhibitory activities of the three complexes were tested. All three complexes showed strong inhibitory activity againstjack beanurease with an IC50value of 6.8, 5.5, and 3.5 μM compared with the acetohydroxamic acid (IC50 = 7.5 μM), which was a positive control. [ABSTRACT FROM AUTHOR]

Gamboge is a dry resin secreted from Garcinia hanburryi, and gambogenic acid (GNA) is one of the main active compounds of gamboge. We have previously demonstrated the anticancer activity of GNA in A549 cells and pointed out its potential effects in anticancer therapies. Previous studies reported that GNA induced apoptosis in many cancer cell lines and inhibited A549 tumor growth in xenograft of nude mice in vivo. However, the anticancer mechanism of GNA has still not been well studied. In this paper, we have investigated whether GNA-induced apoptosis is critically mediated by the p38 mitogen-activated protein kinase (MAPK) pathway. Our findings revealed that GNA could induce apoptosis, inhibit proliferation, down-regulate the expression of p38 and MAPK, increase the activations of caspase-9, caspase-3, and cytochrome c release. Furthermore, using SB203580, an adenosine triphosphate-competitive inhibitor of p38 MAPK, inhibit the expression of p-p38 and the experimental results show that it may promote the occurrence of apoptosis induced by GNA. Taken together, these results suggested that up-regulation of the p38 MAPK cascade may account for the activation of GNA-induced apoptosis. [ABSTRACT FROM AUTHOR]

Arsenic trioxide (ATO) is an effective therapeutic agent for acute promyelocytic leukemia (APL) and other hematopoietic malignancies. We found that ATO down-regulated the global DNA methylation level in HL-60 cells with high-performance capillary electrophoresis (HPCE) assay. Using combination index method of Chou and Talalay, interactions between ATO and epigenetic therapeutic agents were analyzed in three human leukemia cell lines (HL-60, U937, and K562). A synergistic interaction was observed in HL-60 cells between ATO and 5-Aza-2′-Deoxycytidine (DAC), while an antagonistic interaction was found in U937 cells between ATO and valproic acid (VPA). The combination of ATO with trichostatin A (TSA) caused an antagonistic interaction in U937 and K562 cells. These results not only highlight possible diversity of the anti-leukemia mechanisms of ATO, but also provide initial guide for further investigation of leukemia therapies based on the combination of ATO with epigenetic agents. [ABSTRACT FROM AUTHOR]