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Bei Zhang

Publications and source records attributed to Bei Zhang.

At least 19 recordsLinked to original sources
PubMed2026

Transcriptomic Insights into Acupuncture Mechanisms in Protecting Ovarian Function in Mice with Premature Ovarian Insufficiency.

OBJECTIVE: To explore the molecular mechanisms underlying the protective effect of acupuncture on ovarian function in mice with cyclophosphamide-induced premature ovarian insufficiency (POI) via transcriptomic analysis. METHODS: Twenty female C57BL/6 mice were divided into 4 groups: control, model, acupuncture, and non-meridian/non-acupoint (NOMA). POI was induced in the model, acupuncture, and non-meridian/non-acupoint groups via cyclophosphamide injection. The acupuncture group received acupuncture at Guanyuan (CV 4), bilateral Guilai (ST 29), and Sanyinjiao (SP 6) for 3 weeks. After the intervention, ovarian tissue weight and ovarian coefficient were calculated, serum levels of key reproductive hormones including follicle-stimulating hormone (FSH), luteinizing hormone (LH) and anti-M&#xfc;llerian hormone (AMH) were detected, and ovarian histopathological changes were observed to evaluate ovarian function. Transcriptome sequencing was performed to identify differentially expressed genes (DEGs), followed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses to explore key functional terms and signaling pathways. Western blot was finally applied to validate the expression of core proteins related to mitochondrial function, endoplasmic reticulum stress and inflammatory pathways. RESULTS: The model group showed reduced ovarian weight and elevated FSH levels. The acupuncture group exhibited significantly higher ovarian weight and coefficient, lower FSH levels, and increased E2 and AMH levels compared to the model group (all P<0.01). Transcriptomic analysis revealed 4,021 DEGs between groups. GO and KEGG analyses revealed that these DEGs were mainly involved in oocyte development, steroid hormone synthesis, and pathways related to mitochondrial function, endoplasmic reticulum stress, and inflammatory signaling. Western blot analysis showed that acupuncture partially restored mitochondrial function markers cytochrome c oxidase subunit IV and NADH dehydrogenase 1 beta subcomplex subunit 8 and reduced endoplasmic reticulum stress markers (glucose-regulated protein 78 and Calnexin, P<0.01). It also downregulated pro-inflammatory proteins (IL-17R, IL-17A, NF-&#x3ba;B p65, p-NF-&#x3ba;B p65, ERK1/2, and p-ERK1/2) and upregulated proteins related to metabolic homeostasis (peroxisome proliferator-activated receptor &#x3b3;, receptor-interacting protein 140, nicotinamide phosphoribosyltransferase, and sirtuin 1, P<0.01). CONCLUSION: Acupuncture effectively alleviates cyclophosphamide-induced POI in mice, improves ovarian function and follicular quality by regulating cellular functions and inflammatory pathways, suggesting a novel therapeutic approach for POI.

acupuncture↗
PubMed2024

Dysfunction of ATP7B Splicing Variant Caused by Enhanced Interaction With COMMD1 in Wilson Disease.

BACKGROUND & AIMS: The association between Wilson disease and various ATP7B mutations is well-established; however, the molecular mechanism underlying the functional consequence of these mutations, particularly the splicing mutations, remains unclear. This study focused on the ATP7B c.1543+1G>C variant, to reveal a universal pathogenic mechanism of the ATP7B mutants with altered N-terminus. METHODS: The splicing assay and RNA pull-down were performed to explore the mechanism of the aberrant splicing. The ATP7B knockout HuH-7 cell line and Atp7b-/- mice were created, and the functional consequence of the mutant ATP7B were evaluated in&#xa0;vitro and in&#xa0;vivo. RESULTS: The c.1543+1G>C mutation resulted in the skipping of ATP7B exon 3, and the mutant ATP7B showed a loss of trans-Golgi network localization and was degraded via the ubiquitin-proteasome pathway, facilitated by enhanced interactions with COMMD1. Elevated intercellular copper concentration and reduced survival rate were observed in HuH-7 cells expressing mutant ATP7B. Restoration of wild-type ATP7B in Atp7b-/- mice resulted in a substantial improvement in phenotype, whereas mice treated with mutant ATP7B did not demonstrate equivalent benefits. CONCLUSIONS: Our research investigated the pathogenicity and mechanism of ATP7B c.1543+1G>C variant, with particular focus on its enhanced interaction with COMMD1 as a potential universal mechanism contributing to the dysfunction of various ATP7B variants. These findings provide a foundation for the development of innovative therapeutic strategies that target abnormal splicing events in a range of hereditary diseases, including Wilson disease.

Copper-Transporting ATPases↗
PubMed2006

A biocompatible method of decorporation: bisphosphonate-modified magnetite nanoparticles to remove uranyl ions from blood.

We report on the use of bisphosphonate to functionalize Fe3O4 magnetic nanoparticles via dopamine (DA) linkage. Using tetraethyl-3-aminopropane-1,1-bisphosphonate (BP) as the functional molecule, we created a system with an Fe3O4-DA-BP nanostructure, which possesses high specificity for removing uranyl ions from water or blood. This work demonstrates that magnetic nanoparticles, combined with specific receptor-ligand interactions, promise a sensitive and rapid platform for the detection, recovery, and decorporation of metal toxins from biological environment.

Biocompatible Materials↗
PubMed2006

(3R)-4-[(3R)-3-Amino-4-(2,4,5-trifluorophenyl)butanoyl]-3-(2,2,2-trifluoroethyl)-1,4-diazepan-2-one, a selective dipeptidyl peptidase IV inhibitor for the treatment of type 2 diabetes.

Replacement of the triazolopiperazine ring of sitagliptin (DPP-4 IC(50)=18nM) with 3-(2,2,2-trifluoroethyl)-1,4-diazepan-2-one gave dipeptidyl peptidase IV (DPP-4) inhibitor 1 which is potent (DPP-4 IC(50)=2.6nM), selective, and efficacious in an oral glucose tolerance test in mice. It was selected for extensive preclinical development as a potential back-up candidate to sitagliptin.

Animals↗
PubMed2006

Major histocompatibility complex variation in the endangered crested ibis Nipponia nippon and implications for reintroduction.

The major histocompatibility complex (MHC), with its extraordinary levels of genetic variation, is thought to be an essential aspect of the ability of an organism to recognize different parasites and pathogens. It has also been proposed to regulate reproductive processes in many aspects. Here we examine the genetic variation of the second exon of the MHC class II B genes of the crested ibis, an endangered species known to descend from just two breeding pairs rediscovered in 1981. Only five alleles are identified by single-strand conformation polymorphism (SSCP) analysis of 36 samples taken from both wild and captive populations, and a comparatively low level of divergence between MHC alleles is observed. We suggest that representative sampling of individuals with most of the different MHC allele genotypes to constitute a founder population, together with the monitoring of the pathogen status of candidate sites before release, is of great importance for raising the success rate of reintroduction for the crested ibis.

Amino Acid Sequence↗
PubMed2006

Inhibitive effect of genistein on hypoxia-induced basic fibroblast growth factor expression in human retinal pigment epithelium cells.

AIM: The time course changes of basic fibroblast growth factor (bFGF) expression induced by hypoxia and the effects of genistein on hypoxia-induced bFGF expression in the human retinal pigment epithelium (RPE) cells were studied. METHODS: The bFGF mRNA expression was examined by reverse transcription polymerase chain reaction. The bFGF protein expression was detected by Western blot. RESULTS: Hypoxia significantly increased bFGF mRNA expression. The maximal level detected at 24 h was approximately two times that at the start of treatment. With pretreatment of genistein (10, 20, 50, 100, and 200 microM) for 30 min, the elevated expression of bFGF mRNA was suppressed in a concentration-dependent manner. bFGF mRNA expression was reduced to 30.4% by 200 microM of genistein when compared with that untreated with genistein. Hypoxia treatment also remarkably increased the expression of bFGF protein. At 24 h after hypoxia, when the highest expression of bFGF protein was observed, it was approximately two times as much as that at the start of treatment. Genistein (10, 20, 50, 100, and 200 microM) could also suppress bFGF protein expression in a concentration-dependent manner. The highest suppression was observed when exposed to 200 microM of genistein, which was 43% of control. CONCLUSIONS: These results suggested that suppression of bFGF expression in RPE cells might partly account for the inhibitive effect of genistein on retinal neovascularization in vivo.

Angiogenesis Inhibitors↗
PubMed2006

Recurrence of lattice corneal dystrophy caused by incomplete removal of stroma after deep lamellar keratoplasty.

PURPOSE: To report clinical and histopathological characteristics of postoperative amyloidosis recurrence in a patient with lattice corneal dystrophy (LCD) type I. METHODS: The clinical manifestation of recurrent amyloidosis in the residual stroma was delineated in a patient with LCD type I after deep lamellar keratoplasty (DLKP) for 6.5 years. Complete removal of the residual recipient stroma and regrafting of a new cryopreserved donor button were accomplished by a secondary DLKP. The primary DLKP donor graft and the underlying residual stroma of the recipient obtained by the secondary DLKP were examined for analysis of histopathologic and ultrastructural changes. RESULTS: A tongue-shaped retained stroma with linear opacity was observed underneath the primary DLKP donor graft. The retained stromal layer was thoroughly detached from Descemet membrane, removed, and followed by grafting a new cryopreserved button. The primary donor button exhibited a normal epithelium, fewer keratocytes, an intact Descemet membrane, and mild positive Congo red staining in the middle layer of the stroma. The total retained recipient stroma removed by the secondary DLKP measured approximately 20 mum in thickness, showing thick and massive amyloid accumulation. The surface of the removed residual stroma toward Descemet membrane showed collagen fibers in an interwoven fashion without bundle structure under a scanning electron microscope. CONCLUSION: Incomplete removal of the recipient stroma by DLKP can lead to the recurrence of amyloidosis in the residual stroma in patients with LCD. Clinical and histologic findings in the primary graft and in the residual recipient stroma implicate stromal genesis of recurrence of LCD after DLKP.

Amyloid↗
PubMed2006

Identification of an HLA-A*0201-restricted cytotoxic T-lymphocyte epitope in rotavirus VP6 protein.

The function of cytotoxic T lymphocytes (CTLs) in rotavirus (RV) infection in humans is poorly understood. To date, no RV-specific human leukocyte antigen (HLA) class I-restricted T-cell epitopes have been described. In this study, four peptides derived from human RV Wa strain VP6 protein were predicted by computer algorithms and verified by an HLA*0201-binding assay. Two peptides with high affinity for HLA-A*0201 molecules were further assessed. The CTLs induced in vitro by P340-348 (TLLANVTAV)-loaded autologous dendritic cells from peripheral blood lymphocytes of HLA-A*0201-matched healthy donors released gamma interferon specifically upon stimulation with P340-348-loaded T2 cells. The CTLs lysed both P340-348-loaded T2 cells and human RV Wa strain-infected HLA-A*0201(+) Caco-2 cells in an antigen-specific and HLA-A*0201-restricted manner. At the same time, P340-348 was shown to be immunogenic in vivo in HLA-A*0201/Kb transgenic mice. It is proposed that P340-348 is an HLA-A*0201-restricted CTL epitope.

Animals↗
PubMed2006

Ginkgo biloba extract suppresses hypertrophy and extracellular matrix accumulation in rat mesangial cells.

AIM: To observe the effects of Ginkgo biloba extract (EGb) on the hypertrophy of mesangial cells and the accumulation of extracellular matrix (ECM) in mesangial cells. METHODS: Cultured mesangial cells were allotted into 7 groups: normal group, solvent control group, high glucose group, low dose of EGb group, moderate dose of EGb group, high dose of EGb group, and captopril group. Activities of cell antioxidases, S phase percentage and G(0)/G(1) phase percentage, collagen IV and laminin, Smad2/3 and Smad7, TGF-beta(1) mRNA were measured by different methods. RESULTS: For EGb-treated groups, when compared with high glucose group, the cell percentage of S phase was raised and the percentage of G(0)/G(1) was lowered. The intensity of oxidative stress was weakened. The expression of Smad2/3 was greatly decreased and Smad7 was increased. Collagen IV, laminin and TGF- beta(1)mRNA were also reduced. CONCLUSION: EGb can suppress cell hypertrophy and the accumulation of ECM in rat mesangial cells, which means it could play a vital role in the delay of glomerulosclerosis in diabetic nephropathy.

Animals↗
PubMed2006

Combined treatment of ionizing radiation with genistein on cervical cancer HeLa cells.

The anticancer agent genistein inhibits cell growth of tumor cell lines from various malignancies. In our study, we investigated the effectiveness of combined treatment of ionizing radiation (IR) with genistein on cervical HeLa cells and its possible mechanism. It was found that the inhibitory rate in cells with combined treatment was significantly higher than that of the cells treated with IR or genistein alone. After treatments of IR (4 Gy) combined with genistein (40 micromol/L), the apoptotic index of the cells was significantly increased and the cells were arrested in the G2/M phase. Survivin mRNA expression increased after IR (4 Gy), while it significantly decreased after combined treatment. These findings indicated that genistein enhanced the radiosensitivity of cervical cancer HeLa cells, and the mechanisms for this action might include increase of apoptosis, decrease of survivin expression, and prolongation of cell cycle arrest.

Antineoplastic Agents, Phytogenic↗
PubMed2006

A double-blind, placebo-controlled trial assessing pramlintide treatment in the setting of intensive insulin therapy in type 1 diabetes.

OBJECTIVE: To assess safety, efficacy, and tolerability of pramlintide dose escalation with proactive mealtime insulin reduction, followed by insulin optimization, in patients with type 1 diabetes. RESEARCH DESIGN AND METHODS: This 29-week, double-blind, placebo-controlled study randomized 296 patients to pramlintide or placebo as an adjunct to insulin. During initiation, pramlintide was escalated from 15 to 60 microg/meal (15-microg increments) with recommended reductions (30-50%) in mealtime insulin. Insulin was subsequently adjusted to optimize glycemic control. End points included safety and change in HbA1c (A1C), postprandial glucose, insulin, weight, and tolerability. RESULTS: Baseline A1C was 8.1% for both groups and at week 29 had decreased comparably (pramlintide -0.5% [95% CI -0.61 to -0.33]; placebo -0.5% [-0.63 to -0.35]). Pramlintide treatment significantly reduced postprandial glucose excursions (incremental area under the curve [AUC](0-3h): pramlintide -175 +/- 40, placebo -64 +/- 38 mg x h(-1) x dl(-1); P < 0.0005) and weight (pramlintide -1.3 +/- 0.30, placebo +1.2 +/- 0.30 kg; P < 0.0001). At week 29, insulin dose decreased by 28 and 4% in pramlintide- and placebo-treated groups, respectively. Nausea, reported by 63 and 36% of patients in pramlintide and placebo groups (P < 0.01), respectively, was predominately mild to moderate in intensity. Severe hypoglycemia rates were low in both groups (pramlintide 0.57 +/- 0.09, placebo 0.30 +/- 0.06 event rate/patient-year; P < 0.05), with increased rates observed in patients remaining at 30 microg pramlintide. CONCLUSIONS: Pramlintide dose escalation with reduced mealtime insulin was effective during therapy initiation in patients with type 1 diabetes. While both groups experienced equivalent A1C reductions relative to placebo, pramlintide-treated patients experienced reductions in postprandial glucose excursions and weight, not achievable with insulin therapy alone.

Adult↗
PubMed2006

[Expression of the transcription factor PAX5 in childhood acute leukemic cells].

To investigate transcription factor PAX5 expression characteristics in childhood acute leukemic cells, expression levels of PAX5 and CD19 mRNA in 6 hematological tumor cell lines and bone marrow cells of 6 normal children, 58 de novo patients and 4 relapse acute leukemic children, including 39 cases of B-ALL, 10 cases of T-ALL and 13 cases of AML, were detected by a real-time RT-PCR. The results showed that PAX5 and CD19 mRNA expression levels were 2.35% and 2.52% in Namalwa (B-cell lines) respectively, but almost not detectable in other T- and myeloid cell lines. Among clinical samples, expression of PAX5 mRNA in B-ALL was significantly higher than that in T-ALL and AML (P = 0.029 and P = 0.013 respectively). PAX5 expression was significantly lower in T-ALL and AML than that in normal controls. The difference of PAX5 mRNA expression levels between T-ALL and AML was not significant. Individual difference of PAX5 mRNA expression levels in children with B-ALL was great. Moreover, PAX5 mRNA expressions in de novo and relapse patients with B-ALL were significantly higher than those in remission (P = 0.011 and P = 0.006 respectively). As binding sites for B-cell specific activator protein have been identified in the promoter regions of CD19, the study found that in B-ALL, there was clear correlation between the expression levels of PAX5 and CD19, which was also studied by real-time RT-PCR. It is concluded that PAX5 transcripts are readily detectable and quantifiable in clinical materials with B-ALL by real-time RT-PCR. The strong PAX5 mRNA expression in some B-ALL can be considered to be particularly interesting for further analysis.

Adolescent↗
PubMed2006

[A study on expression of HIF-1alpha and EPO in the hippocampus of rats with vascular dementia].

OBJECTIVE: To observe the expression rule of hypoxia inducible factor-1 (HIF-1alpha) and erythropoietion (EPO) in the formation of vascular dementia (VD) and investigate the possible pathogenesis of VD. METHODS: Rats of experimental group were treated with a permanent bilateral common carotid arteries (CCA) occlusion (2-VO) for establishing vascular dementia model. Rats were evaluated on learning-memory ability by Y-type water maze test. The dynamic expression of HIF-1alpha and EPO in hippocampal CA1 region were measured by immunohistochemical assay method. RESULTS: (1) The learning-memory ability of rats in VD groups was progressively decreased as the ischemic duration prolonged (P < 0.05); (2) In VD group, the expression of HIF-1alpha and EPO in hippocampal CA1 region were most obvious at 1 w, and then declined progressively but still above the normal level (P < 0.01); (3) In VD group, the expression of HIF-1alpha and EPO at each ischemic point and their corresponding learning-memory ability were in significant correlation at the 0.01 level. CONCLUSION: Both HIF-1alpha and EPO contribute to the formation of VD, and HIF-1/EPO anoxic signal transduction may play a protecting role in this process.

Animals↗
PubMed2005

[Angiotensin-converting enzyme inhibitors potentiate subthreshold preconditioning through NO and mitoK(ATP) channel.].

The aim of the present study was to determine whether angiotensin-converting enzyme inhibitors (ACEI) could contribute to the protective effects of preconditioning, and to explore its underlying mechanism. The Langendorff model of isolated rat heart was used. Cardiac contractility and lactate dehydrogenase (LDH) in the coronary effluent were measured, and infarct area of hearts after 30 min of ischemia followed by 120 min of reperfusion was analyzed. We found that: (1) The subthreshold preconditioning (2 min of ischemia and 10 min of reperfusion), captopril (an ACEI with sulfhydryl groups) or perindoprilate (an ACEI without sulfhydryl groups) alone did not protect the hearts from being injured by 30 min of ischemia and 120 min of reperfusion. (2) However, the combination of captopril or perindoprilate with subthreshold preconditioning could decrease left ventricular end-diastolic pressure (LVEDP), increase left ventricular developed pressure (LVDP) and coronary flow compared with the subthreshold preconditioned group. The combination treatments also inhibited the release of LDH from ischemia/reperfusion hearts, and reduced the infarct area in ischemic heart after 2 h of reperfusion (P<0.05). (3) By using NOS inhibitor L-NAME (100 mumol/L) before combined administration of ACEI with subthreshold preconditioning, the protection effect triggered by the combination treatment was significantly reduced. Pretreatment of the hearts with mitochondrial ATP-sensitive potassium (mitoK(ATP)) channel inhibitor 5-HD (100 mumol/L) also abolished the protection effect (P<0.05). (4) Subthreshold preconditioning, captopril or perindoprilate alone could enhance the NO content in coronary effluent (P<0.05), but the combination of captopril or perindoprilate with subthreshold preconditioning could further augment the NO content compared with the subthreshold preconditioned group (P<0.05). The results indicate that ACEIs with or without sulfhydryl groups may potentiate the subthreshold preconditioning to trigger cardiac protection effect against the ischemia/reperfusion injury. This protection effect in the heart is possibly mediated by the generation of NO and the activation of mitoK(ATP) channel.

English Abstract↗
PubMed2005

Fungal spectrum identified by a new slide culture and in vitro drug susceptibility using Etest in fungal keratitis.

PURPOSE: To investigate the spectrum of fungal species causing keratitis and to test antifungal drug susceptibility to each isolate using Etest. METHODS: Microbial cultures were performed for patients who were clinically diagnosed with fungal keratitis between September 2002 and July 2004. Modified slide culture was established to identify the fungal species of the isolates. Etest (AB BIODISK, Solna, Sweden) was applied to determine the antifungal agent susceptibility of each isolate to itraconazole, fluconazole, and amphotericin B in vitro, respectively. RESULTS: Among 73 eyes of 73 patients with clinical diagnosis of fungal keratitis, 61 strains of fungi were isolated from 61 eyes. The rate of positive culture was 81.3% of all cases. The spectrum of fungal species involved: 58 (95.1%) isolates of filamentous fungi, including the two most common genera-Fusarium (n = 33, 54.1%) and Aspergillus (n = 9, 14.8%),-followed by 16 (26.2%) isolates of other genera of filamentous fungi such as Alternaria (n = 3, 4.9%), Trichophyton (n = 3, 4.9%), Curvularia (n = 2, 3.3%), Chrysosporium (n = 2, 3.3%), Acremonium (n = 2, 3.3%), and Scedosporium (n = 1, 1.6%), 1 (1.6%) yeast of Candida, as well as two (3.3%) dimorphic fungi of Blastomyces and Sporothrix isolate each. Three filamentous fungi of the isolates failed to be identified according to the information provided by slide culture. The results of Etest showed that 20 (60.6%) isolates of Fusarium were susceptible to amphotericin B, whereas all of them were resistant to itraconazole and fluconazole. All nine (100%) isolates of Aspergillus were sensitive to itraconazole, whereas four (44.4%) of them were sensitive to amphotericin B, and only two (22.2%) of them were sensitive to fluconazole. Seventeen (89.5%), 13 (68.4%), and 10 (52.6%) isolates of the remaining 19 organisms were sensitive to amphotericin B, itraconazole, and fluconazole, respectively. CONCLUSIONS: Fusarium and Aspergillus are the most frequent pathogenic organisms in causing fungal keratitis, whereas other species of fungi can also cause corneal infection. In vitro Etest for assessing antifungal drug susceptibility is a simple and practical method and may provide referential information for clinical consideration of choosing antifungal agents to treat fungal keratitis.

Antifungal Agents↗
PubMed2005

[Magnetic properties and transport behaviors in double doped La(0.67+1.33x)Sr(0.33-1.33x)Mn(1-x)Mg(x)O3 system].

The M-T curves, M-H curves, ESR curves, infrared spectrum, Raman spectrum, rho-T curves and MR-T curves of La(0.67+1.33x)Sr(0.33-1.33x)Mn(1-x)Mg(x)O3 (0.00 < or = x < or = 0.25) were studied. The experiment pointed out that all samples exhibit a paramagnetic-ferromagnetic (PM-FM) transition associated with metallic-insulating (MI) transition in the low doping region, which does not occur in the heavy doping zone. The authors suggest that this behavior is attributed to the difference between the Jahn-Teller distortion of the Mn3+ ion neighboring Mg2+ and that of the Mn3+ ion non-neighboring Mg2+, which is confirmed by the IR and Raman spectra. The anomalous transport behavior is dominated by the differerent Jahn-Teller distortion.

Electron Spin Resonance Spectroscopy↗
PubMed2005

[Apoptosis mechanism in human chronic myelogenous leukemia K562 cells induced by tetra-arsenic tetra-sulfide].

To explore the effects of tetra-arsenic tetra-sulfide (As(4)S(4)) in treatment of human chronic myelogenous leukemia K562 cells and its mechanism, trypan blue staining and microculture MTS assay were used to measure the effects of As(4)S(4) on growth inhibition of K562 cells; the morphologic change was determined by Wright's staining assay. The apoptosis rate and cell cycle were detected by flow cytometry; the changes of transcript and protein level were determined by real-time quantitative RT-PCR and Western blot analysis, respectively. The results indicated that As(4)S(4) had significant cytotoxicity on K562 cells. At the concentration of 0.5 micromol/L, the cell viability decreased significantly after being cultured with As(4)S(4) for 24 hours. When the concentration was lower than 0.1 micromol/L, As(4)S(4) had a little effect on K562 cells. The effect of As(4)S(4) on K562 was time- and concentration- dependent. After being cultured with As(4)S(4) at the concentration of 1.0 micromol/L for 24 to 48 hours, K562 cells displayed typical morphological changes of apoptosis. At a concentration greater than or equal to 1.0 micromol/L, As(4)S(4) could induce apoptosis significantly. After 12 hours of incubation with 1.0 micromol/L As(4)S(4), the apoptosis rate increased from (3.47 +/- 0.42)% to (6.16 +/- 0.98%). At the same time, the percentage of cells in G(1) phase decreased from (69.65 +/- 3.24)% to (50.53 +/- 2.86)%, whereas the percentage of cells in G(2)/M phase increased from (9.56 +/- 2.51)% to (12.91 +/- 2.13)%. The mRNA level of Bcl-X(L) and the protein level of pAkt were down-regulated after the inhibition of As(4)S(4), while the mRNA expression of Bcl-2, Bad and Bax had no change. Both of the transcript and protein level of bcr-abl had no change after incubation with As(4)S(4). It is concluded that As(4)S(4) can inhibit the growth of K562 cells efficiently through inducing apoptosis and cell cycle arrest. It seems that As(4)S(4) interferes with pAkt pathway and down-regulates Bcl-X(L), which may be involved in the response of K562 to this agent.

Antineoplastic Agents↗