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1.
Acta Pharmacol Sin ; 44(7): 1429-1441, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36697978

RESUMO

Aristolochic acid I (AAI) is a well established nephrotoxin and human carcinogen. Cytosolic NAD(P)H quinone oxidoreductase 1 (NQO1) plays an important role in the nitro reduction of aristolochic acids, leading to production of aristoloactam and AA-DNA adduct. Application of a potent NQO1 inhibitor dicoumarol is limited by its life-threatening side effect as an anticoagulant and the subsequent hemorrhagic complications. As traditional medicines containing AAI remain available in the market, novel NQO1 inhibitors are urgently needed to attenuate the toxicity of AAI exposure. In this study, we employed comprehensive 2D NQO1 biochromatography to screen candidate compounds that could bind with NQO1 protein. Four compounds, i.e., skullcapflavone II (SFII), oroxylin A, wogonin and tectochrysin were screened out from Scutellaria baicalensis. Among them, SFII was the most promising NQO1 inhibitor with a binding affinity (KD = 4.198 µmol/L) and inhibitory activity (IC50 = 2.87 µmol/L). In human normal liver cell line (L02) and human renal proximal tubular epithelial cell line (HK-2), SFII significantly alleviated AAI-induced DNA damage and apoptosis. In adult mice, oral administration of SFII dose-dependently ameliorated AAI-induced renal fibrosis and dysfunction. In infant mice, oral administration of SFII suppressed AAI-induced hepatocellular carcinoma initiation. Moreover, administration of SFII did not affect the coagulation function in short term in adult mice. In conclusion, SFII has been identified as a novel NQO1 inhibitor that might impede the risk of AAI to kidney and liver without obvious side effect.


Assuntos
Ácidos Aristolóquicos , Camundongos , Humanos , Animais , Ácidos Aristolóquicos/toxicidade , NAD(P)H Desidrogenase (Quinona)/metabolismo , Rim/patologia , Fígado/metabolismo
2.
Clin Transl Med ; 11(4): e379, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33931972

RESUMO

BACKGROUND AND AIMS: 4-phenylbutyric acid (4-PBA) is a low molecular weight fatty acid that is used in clinical practice to treat inherited urea cycle disorders. In previous reports, it acted as a chemical chaperone inhibiting endoplasmic reticulum (ER) stress and unfolded protein response signaling. A few studies have suggested its function against hepatic fibrosis in mice models. However, its role in hepatocarcinogenesis remained unknown. METHODS: 4-PBA was administered alone or in combination with diethylnitrosamine to investigate its long-term effect on liver tumorigenesis. The role of 4-PBA in oncogene-induced hepatocellular carcinoma (HCC) mice model using sleeping beauty system co-expressed with hMet and ß-catenin point mutation (S45Y) was also observed. RNA-seq and PCR array were used to screen the pathways and genes involved. In vitro and in vivo studies were conducted to explore the effect of 4-PBA on liver and validate the underlying mechanism. RESULTS: 4-PBA alone didn't cause liver tumor in long term. However, it promoted liver tumorigenesis in HCC mice models via initiation of liver cancer stem cells (LCSCs) through Wnt5b-Fzd5 mediating ß-catenin signaling. Peroxisome proliferator-activated receptors (PPAR)-α induced by 4-PBA was responsible for the activation of ß-catenin signaling. Thus, intervention of PPAR-α reversed 4-PBA-induced initiation of LCSCs and HCC development in vivo. Further study revealed that 4-PBA could not only upregulate the expression of PPAR-α transcriptionally but also enhance its stabilization via protecting it from proteolysis. Moreover, high PPAR-α expression predicted poor prognosis in HCC patients. CONCLUSIONS: 4-PBA could upregulate PPAR-α to initiate LCSCs by activating ß-catenin signaling pathway, promoting HCC at early stage. Therefore, more discretion should be taken to monitor the potential tumor-promoting effect of 4-PBA under HCC-inducing environment.


Assuntos
Carcinoma Hepatocelular/induzido quimicamente , Neoplasias Hepáticas/induzido quimicamente , Células-Tronco Neoplásicas/efeitos dos fármacos , PPAR alfa/metabolismo , Fenilbutiratos/farmacologia , Animais , Carcinogênese/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Via de Sinalização Wnt/efeitos dos fármacos
3.
Acta Pharmacol Sin ; 42(2): 282-289, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32555508

RESUMO

Identification of the functional impact of mutated and altered genes in cancer is critical for implementing precision oncology and drug repurposing. In recent years, the emergence of multiomics data from large, well-characterized patient cohorts has provided us with an unprecedented opportunity to address this problem. In this study, we investigated survival-associated genes across 26 cancer types and found that these genes tended to be hub genes and had higher K-core values in biological networks. Moreover, the genes associated with adverse outcomes were mainly enriched in pathways related to genetic information processing and cellular processes, while the genes with favorable outcomes were enriched in metabolism and immune regulation pathways. We proposed using the number of survival-related neighbors to assess the impact of mutations. In addition, by integrating other databases including the Human Protein Atlas and the DrugBank database, we predicted novel targets and anticancer drugs using the drug repurposing strategy. Our results illustrated the significance of multidimensional analysis of clinical data in important gene identification and drug development.


Assuntos
Antineoplásicos/farmacologia , Reposicionamento de Medicamentos/métodos , Neoplasias/genética , Bases de Dados Factuais , Desenvolvimento de Medicamentos/métodos , Humanos , Terapia de Alvo Molecular , Mutação , Neoplasias/patologia , Sobrevida
4.
Int J Biol Macromol ; 129: 140-151, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30731163

RESUMO

Previous study has shown heterogeneous nuclear ribonucleoprotein A1(HNRNPA1) is highly expressed in various human cancers. In order to study the clinical value and potential function of HNRNPA1 in HBV-related hepatocellular carcinoma (HCC), three datasets from the GEPIA, GEO and TCGA were analyzed. HNRNPA1 expression was found to be significantly higher in HBV-positive HCC samples, which was supported with IHC validation. Both GO and KEGG analyses demonstrated that HNRNPA1 co-expressed genes were involved in translation, ribonucleoprotein complex biogenesis and assembly, ribosome biogenesis, RNA processing, RNA splicing, etc. Survival analysis showed a significant reduction in overall survival of patients with high HNRNPA1 expression from both the GSE14520 cohort and 151 patients with HBV-related HCC cohort. Furthermore, Gene set enrichment analysis (GSEA) revealed that HNRNPA1 may regulate HCC progression by influencing the cell cycle and WNT signaling pathway, etc. HNRNPA1 overexpression has diagnostic value in distinguishing between HCC and non-HCC liver tissue (AUC = 0.730). Finally, HNRNPA1 was a directly target gene of miR-22 manifested by the reduced luciferase activity and decreased HNRNPA1 expression in the cells with overexpression of miR-22. HNRNPA1 might function as an oncogene through the EGFR signaling pathway in HBV-related HCC, which has not been reported in previous studies.


Assuntos
Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/mortalidade , Vírus da Hepatite B , Hepatite B/complicações , Ribonucleoproteína Nuclear Heterogênea A1/genética , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/mortalidade , Adulto , Idoso , Biomarcadores Tumorais , Carcinoma Hepatocelular/diagnóstico , Linhagem Celular Tumoral , Biologia Computacional/métodos , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Genes Reporter , Hepatite B/virologia , Ribonucleoproteína Nuclear Heterogênea A1/metabolismo , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/diagnóstico , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico
5.
Fish Physiol Biochem ; 45(1): 199-208, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30242696

RESUMO

The γ-aminobutyric acid type A (GABAA) receptor is an important pentameric inhibitory neurotransmitter receptor, and the γ2 subunit of this receptor plays a key role in potentiation of the GABAA response. We previously detected that the expression of GABAA receptor in the livers of Carassius auratus gibelio significantly increased after medication (avermectin and difloxacin treatment). In order to better understand the mechanism of action of the GABAA receptor γ2 subunit in the livers of C. auratus gibelio, we constructed a C. auratus gibelio liver cDNA library (the titer value of 1.2 × 106 cfu/mL) and identified the proteins that interact with the GABAA receptor γ2 subunit by using a yeast two-hybrid assay. The yeast two-hybrid screening yielded seven positive clones, namely, prelid3b, cdc42, sgk1, spg21, proteasome, chia.5, and AP-3 complex subunit beta-1, all of which have been annotated by the NCBI database. The functions of these proteins are complex; therefore, additional studies are required to determine the specific interactions of these proteins with the GABAA receptor γ2 subunit in the liver of C. auratus gibelio. Although the interactions identified by the yeast two-hybrid system should be considered as preliminary results, the findings of this study may provide further direction and a foundation for future research focusing on the mechanisms of the GABAA receptor γ2 subunit in C. auratus gibelio livers.


Assuntos
Carpa Dourada/fisiologia , Fígado/metabolismo , Receptores de GABA-A/metabolismo , Animais , Regulação da Expressão Gênica , Ligação Proteica , Técnicas do Sistema de Duplo-Híbrido
6.
J Cell Biochem ; 119(10): 8035-8047, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29377305

RESUMO

Calcium binding protein calbindin-D28K (CaBP28K) mediates the relationship between vitamin D and calcium, but its mechanism remains unclear during bone formation. The present study reports that maternal CaBP28K levels were positively correlated with paired umbilical cord CaBP28K levels. In addition, CaBP28K levels were positively correlated with the body length, and head and chest circumferences of neonates, but negatively correlated with maternal 25(OH)D3 levels. CaBP28K was also downregulated in MC3T3-E1 osteoblasts when treated with 1,25(OH)2D or VDR overexpression, but was upregulated in the femur of 1α(OH)ase(-/-) mice. Furthermore, it was found CaBP28K may influence cell differentiation and matrix formation through the regulation of DMP1 and the interaction with MMP13 in osteoblasts. This suggests that CaBP28K could be a candidate for the negative role of 1,25(OH)2D/VDR in regulating bone mass.


Assuntos
Calbindina 1/metabolismo , Calcitriol/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Metaloproteinase 13 da Matriz/metabolismo , Osteogênese/fisiologia , Receptores de Calcitriol/metabolismo , Adolescente , Adulto , Animais , Calbindina 1/genética , Linhagem Celular , Proteínas da Matriz Extracelular/genética , Feminino , Humanos , Metaloproteinase 13 da Matriz/genética , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Osteogênese/genética , Adulto Jovem
7.
Radiat Oncol ; 12(1): 92, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28569169

RESUMO

BACKGROUND: This study aimed to highlight the type of tumor thrombus and identify the prognostic factors influencing the long-term survival outcomes in patients with hepatocellular carcinoma (HCC) having a tumor thrombus. A tumor thrombus in HCC is associated with poor prognosis. METHODS: Eighty patients diagnosed with HCC having a tumor thrombus between May 2006 and April 2014 were enrolled in this study. Age, gender, clinical characteristics, laboratory findings, Child-Pugh classification, performance status (ECOG), types of tumor thrombi, radiotherapy method, biologically effective dose (BED), and primary treatment method were analyzed to identify the prognostic factors associated with the overall survival (OS) rates. Statistical analyses were performed using SPSS version 19.0. RESULTS: The median follow-up duration was 24 months (range 6-90). The 1-, 3-, and 5-year OS rates of the patients were 77.6%, 37.6%, and 18.8%, respectively. On univariate analysis, gender, radiotherapy method, BED, types of tumor thrombi, Child-Pugh classification, ECOG, and total bilirubin were associated with OS (P < 0.001, P = 0.001, P = 0.016, P = 0.003, P < 0.001, P < 0.001, P = 0.039, respectively). The prognostic factors for OS in multi-variate analyses were gender (P < 0.001), BED (P = 0.044), Child Pugh classification (P = 0.020), performance status (ECOG) (P = 0.004), and types of tumor thrombi (P = 0.001). The median OS for the high-BED group was better than that for the low-BED groups (42 months vs. 19 months, P = 0.016). CONCLUSIONS: Gender, BED, performance status (ECOG), Child-Pugh classification, and types of tumor thrombi seemed to affect OS, and a stepwise decrease in survival was observed with the types of tumor thrombi ranging from I to IV. High-BED palliative radiotherapy might improve the long-term outcomes for patients with HCC having a tumor thrombus.


Assuntos
Carcinoma Hepatocelular/mortalidade , Neoplasias Hepáticas/mortalidade , Cuidados Paliativos , Trombose/mortalidade , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/radioterapia , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/radioterapia , Masculino , Pessoa de Meia-Idade , Prognóstico , Dosagem Radioterapêutica , Estudos Retrospectivos , Taxa de Sobrevida , Trombose/patologia , Trombose/radioterapia
8.
Medicine (Baltimore) ; 96(26): e7343, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28658151

RESUMO

To establish a risk scoring system for predicting locoregional recurrence (LRR) and explore the potential value of radiotherapy in T1 to T2 node-negative breast cancer patients treated with mastectomy. From January 2001 to February 2008, a total of 353 node-negative T1 to T2 breast cancer cases treated with mastectomy without adjuvant radiotherapy were retrospectively analyzed. Preliminary screening of the prognostic factors was accomplished by Kaplan-Meier univariate analysis, and survival curves between different groups were compared by log-rank test. Risk factors were determined using Cox proportional hazards model. A categorical risk scoring system was generated according to the Cox model, weighing the relative importance of each risk variable. Median follow-up was 115.7 months (range, 1.2-238.4 months). The overall 5-year locoregional recurrence-free survival (LRFS) was 89.8% (95% confidence interval [CI] = 86.7%-92.9%). Chest wall (53.8%) was found to be the most common site of LRR, followed by supraclavicular nodes (48.7%). Age ≤40 years, primary tumor size ≥4.5 cm and number of nodes resected ≤10 were found to be independent factors for poor prognosis of LRR. Two risk stratifications based on the scoring system were subsequently obtained. The 5-year LRFS was 91.6% (95% CI = 88.5%-94.7%) with low risk (score <2) and 75.7% (95% CI = 61.8%-89.6%) with high risk (score ≥2), respectively (χ = 7.544, P = .006). In addition, significant differences in overall survival (P = .045) and disease-free survival (P = .019) were presented between them. Patients with T1-2N0M0 breast cancer achieved favorable prognosis in general. Those with risk factors, including age ≤40 years, primary tumor size ≥4.5 cm and number of nodes resected ≤10, were at higher risk of LRR. The established scoring system could help to distinguish the subgroups that might potentially benefit from postoperative radiotherapy.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/cirurgia , Mastectomia , Recidiva Local de Neoplasia/diagnóstico , Medição de Risco/métodos , Adulto , Fatores Etários , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Tomada de Decisão Clínica , Intervalo Livre de Doença , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Análise Multivariada , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Prognóstico , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Estudos Retrospectivos , Fatores de Risco , Carga Tumoral
9.
Biomed Res Int ; 2016: 5382047, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27738632

RESUMO

Purpose. This study aimed to evaluate the characteristics of the HVGGSSV peptide, exploring radiation-guided delivery in a mouse model of nasopharyngeal carcinoma. Methods. Mice with CNE-1 nasopharyngeal carcinoma were assigned to two different groups treated with Cy7-NHS and Cy7-HVGGSSV, respectively. Meanwhile, each mouse received a single dose of 3 Gy radiation. Biological distribution of the recombinant peptide was assessed on an in vivo small animal imaging system. Results. The experimental group showed maximum fluorescence intensity in irradiated tumors treated with Cy7-labeled HVGGSSV, while untreated (0 Gy) control tumors showed lower intensity levels. Fluorescence intensities of tumors in the right hind limbs of experimental animals were 7.84 × 107 ± 1.13 × 107, 1.35 × 108 ± 2.66 × 107, 4.05 × 108 ± 1.75 × 107, 5.57 × 108 ± 3.47 × 107, and 9.26 × 107 ± 1.73 × 107 photons/s/cm2 higher compared with left hind limb values at 1, 2, 15, 24, and 48 h, respectively. Fluorescence intensities of tumor in the right hind limbs of the experimental group were 1.66 × 108 ± 1.71 × 107, 1.51 × 108 ± 3.23 × 107, 5.38 × 108 ± 1.96 × 107, 5.89 × 108 ± 3.57 × 107, and 1.62 × 108 ± 1.69 × 107 photons/s/cm2 higher compared with control group values at 1, 2, 15, 24, and 48 h, respectively. Fluorescence was not specifically distributed in the control group. Compared with low fluorescence intensity in the heart, lungs, and tumors, high fluorescence distribution was found in the liver and kidney at 48 h. Conclusions. HVGGSSV was selectively bound to irradiated nasopharyngeal carcinoma, acting as a targeting transport carrier for radiation-guided drugs that are mainly metabolized in the kidney and liver.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Raios gama , Neoplasias Nasofaríngeas/terapia , Neoplasias Experimentais/terapia , Peptídeos/farmacologia , Animais , Carcinoma , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Camundongos Nus , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(2): 523-6, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-25970925

RESUMO

Coupled plasma atomic emission spectrometry (ICP-AES) was used to determine the trace impurities of Ca, Mg, Al, Fe and Si in industrial sodium chromate. Wavelengths of 167.079, 393.366, 259.940, 279.533 and 251.611 nm were selected as analytical lines for the determination of Al, Ca, Fe, Mg and Si, respectively. The analytical errors can be eliminated by adjusting the determined solution with high pure hydrochloric acid. Standard addition method was used to eliminate matrix effects. The linear correlation, detection limit, precision and recovery for the concerned trace impurities have been examined. The effect of standard addition method on the accuracy for the determination under the selected analytical lines has been studied in detail. The results show that the linear correlations of standard curves were very good (R2 = 0.9988 to 0.9996) under the determined conditions. Detection limits of these trace impurities were in the range of 0.0134 to 0.0280 mg x L(-1). Sample recoveries were within 97.30% to 107.50%, and relative standard deviations were lower than 5.86% for eleven repeated determinations. The detection limits and accuracies established by the experiment can meet the analytical requirements and the analytic procedure was used to determine trace impurities in sodium chromate by ion membrane electrolysis technique successfully. Due to sodium chromate can be changed into sodium dichromate and chromic acid by adding acids, the established method can be further used to monitor trace impurities in these compounds or other hexavalent chromium compounds.

11.
Huan Jing Ke Xue ; 31(8): 1755-61, 2010 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-21090289

RESUMO

Organic carbon (OC) and elemental carbon (EC) in PM2.5 samples collected in urban (Xujiahui) and industrial (Baoshan) areas in Shanghai during 2007-2008 were analyzed with a DRI carbon analyzer using IMPROVE-TOR protocol. The results showed that the seasonal average concentrations of OC and EC were highest in the winter and lowest in the summer. The annual average concentrations of OC and EC were 8.10 and 3.91 microg x m(-3) at the urban sampling site, and 11.91 and 4.69 microg x m(-3) in the industrial area. The annual average OC/EC ratios at the two sites were 2.01 and 2.42, respectively. Strong correlations (R2 0.52-0.87) between OC and EC were found in all seasons, with the highest correlation coefficients in the winter ( R2 0.87 and 0.80) and the lowest in the spring (R2 0.52 and 0.58), indicating that the pollutant sources in spring was more complicated due to the varying wind directions. The annual average concentrations of secondary organic carbon (SOC) were 2.72 and 5.07 microg x m(-3) at the urban and industrial sites, accounting for about 30% of the total OC. The contribution of SOC to OC was the highest (about 40%) in the summer, in accordance with the high temperature and strong solar radiation in the summer. It was also found that precipitation had significant impact on the concentrations of OC and EC, especially in the winter. The average concentrations during periods without precipitation were two times higher than that during periods with precipitation in the winter, whereas no significant difference was found between the concentrations of OC and EC in the periods with and without precipitation in the summer, possibly due to the more stable atmospheric conditions during the periods with precipitation in comparison with those without precipitation. The OC/EC and SOC/OC ratios decreased significantly during precipitation.


Assuntos
Poluentes Atmosféricos/análise , Carbono/análise , Monitoramento Ambiental , Material Particulado/análise , Aerossóis/análise , China , Cidades , Compostos Orgânicos/análise , Tamanho da Partícula , Chuva , Estações do Ano
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(3): 829-33, 2010 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-20496720

RESUMO

A rapid multi-element analysis method for clay mineral samples was described. This method utilized a polarized wave-length dispersive X-ray fluorescence spectrometer--Axios PW4400, which had a maximum tube power of 4 000 watts. The method was developed for the determination of As, Mn, Co, Cu, Cr, Dy, Ga, Mo, P, Pb, Rb, S, Sr, Ni, ,Cs, Ta, Th, Ti, U, V, Y, Zn, Zr, MgO, K2O, Na2O, CaO, Fe2O3, Al2O3, SiO2 and so on. Thirty elements in clay mineral species were measured by X-ray fluorescence spectrometry with pressed powder pellets. Spectral interferences, in particular the indirect interferences of each element, were studied. A method to distinguish the interference between each other periodic elements in element periodic table was put forward. The measuring conditions and existence were mainly investigated, and the selected background position as well as corrected spectral overlap for the trace elements were also discussed. It was found that the indirect spectral overlap line was the same important as direct spectral overlap line. Due to inducing the effect of indirect spectral overlap, some elements jlike Bi, Sn, W which do not need analysis were also added to the elements channel. The relative standard deviation (RSD) was in the range of 0.01% to 5.45% except three elements Mo, Cs and Ta. The detection limits, precisions and accuracies for most elements using this method can meet the requirements of sample analysis in clay mineral species.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(8): 2268-71, 2009 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-19839355

RESUMO

In the present paper a method for the determination of strontium, barium, calcium, magnesium, silicon, iron, aluminum and sulfur in the product of strontium carbonate by X-ray fluorescence spectrometry with pressed powder sample preparation was developed, and the standard samples were synthesized by high purity reagent. As the contents of strontium in the product of strontium carbonate were very high, the phenomenon of spectrum-peak-saturated occurred and the count rate was overflowed according to the measuring condition which was automatically given by the software system of X-ray fluorescence spectrometry. As a result, the deviation of the measurement is greater. According to analyzing the measuring condition of strontium, a method was given for reducing the count rate by reducing the measuring power of strontium, thus achieving the goal of measurement. When sulfate was measured with pressed powder sample, the results were enhanced with the increase in measuring number. In light of this situation, a method was proposed to solve the problem. As the self-forming characteristic of the product of strontium carbonate was not so well, it was very difficult to press the sample successfully. So, the condition of squash method involving the kinds of the adhesives, the mixing technique with powder sample and the pressing-time technique was discussed. During making the sample, it was found that the effects of pellet formation were better if the time could be delayed by 120 seconds. Matrix effect was corrected by alpha coefficient method, the accuracy of the method was evaluated by analysis of synthetic sample. Detection limits of 0.623-107.6 mg x g(-1) were obtained. The results were in good agreement with certified values with precision of < 2.5% RSD.

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