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Objective To establish a method of solid phase extraction-reversed-phase high performance liquid chromatography(SPE-HPLC)for determination of methomyl in plasma of rat.Methods The sample pretreatment method,the test conditions,the linear range,the sensitivity,the specificity,the precision, the accuracy,the stability and the recoveries for plasma were investigated by using rat plasma spiked with standard methomyl and intemal standard substance.Results The linear range was 0.1～20μg/mL ( r= 0.9993,P<0.001).The limit of detection was 0.03μg/mL(S/N ≥3).The intra and inter-day precision of assay for methomyl was less than 8.33%and 11.11%in plasma respectively.The intra and inter-day accuracy of assay for methomyl was between 90%and 120%in plasma respectively.The recoveries for methomyl were more than 88%±4.4%in plasma.Conclusion The HPLC method for quantitative and qualitative analysis of methomyl is simple,rapid and accurate,which is suitable for the identification of methomyl in the cases.
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We studied the effect of photodynamic therapy with phycobiliproteins on human liver cancer cells in vitro. With 3-(4, 5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT assay), we used two phycobiliproteins, R-phycoerythrin (R-PE) and C-phycocyanin (C-PC) prepared from Porphyra yezoensis, to determine the killing rates and apoptosis rates of human liver cancer cells (SMMC-7721) mediated by laser. When the concentration of R-PE was 120 mg/L, the survival rate of human liver cancer cells was 27% after treated by Argon laser with 100 J/cm2 doses, while the survival rate in the control group (without adding R-PE) was 65%. When the C-PC concentration was 120 mg/L, the survival cell rate was 47% after treated by He-Ne laser with 35 J/cm2 dose, while the survival rate in the control group (without adding C-PC) was 70%. After handled only with these two kinds of phycobiliproteins for 72 h, the growth of cancer cells presented significant inhibition. The maximal inhibition rates reached up to 31% with R-PE (120 mg/L concentration) and 27% with C-PC (250 mg/L concentration) respectively. After irradiated by laser for 8 h, the maximal cell apoptosis rates were 31.54% with R-PE and 32.54% with C-PC, respectively. It indicated that R-PE and C-PC extracted from Porphyra yezoensis could develop to new photosensitizers for cancer photodynamic therapy.
Subject(s)
Humans , Apoptosis , Radiation Effects , Cell Line, Tumor , Lasers , Liver Neoplasms , Pathology , Photochemical Processes , Photochemotherapy , Methods , Phycobiliproteins , Pharmacology , Phycoerythrin , Pharmacology , Porphyra , ChemistryABSTRACT
AIM: It is tested that the suppressive effects of (-)-Epigallocatechin-3-gallate (EGCG ) on the migration, invasion and RhoA expression of human lung carcinoma 95-D cells and B16BL6 melanoma cells invasion in vivo,which will possibly help to understand the molecular mechanisms by which EGCG inhibits the invasion of tumor cells. METHODS: The inhibitory effect of EGCG on the migration of 95-D cells was tested by cell migration assay. Cell invasion was analyzed by the matrigel invasion assay. Assay of tumor metastasis in an animal model, RT-PCR and Western blot analysis of expression of RhoA was also performed. RESULTS:EGCG was effective in inhibiting the migration of 95-D cells in a dose-dependent manner. EGCG dose-dependently inhibited 95-D cells invasion in vitro and 40 μmol·L-1 EGCG exhibited 79.9% inhibition and EGCG 50 mg·kg-1·d-1 for 3 weeks inhibited B16BL6 melanoma cells invasion by 71.7% in vivo. EGCG could down-regulate the expression of RhoA. CONCLUSION: EGCG strongly inhibits metastasis of 95-D cells, and the mechanism of EGCG is possible associated with the inhibition of RhoA expression.
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Objective: No complete study has been reported on methomyl and its metabolite in rat plasma at home and abroad.This study aimed to detect methomyl and its metabolite in rat plasma by high performance liquid chromatography-mass spectrometry(HPLC-MS).Methods: Ten Wistar rats received intragastric administration of methomyl 50mg/kg,and then executed and kept at room temperature for 72 hours.After that,methomyl and its metabolite in the heart-blood of the rats were determined by solid phase extraction(SPE) and HPLC-MS.Results: Compared with the blank controls,methomyl and its metabolite were detected in the plasma of the experimental rats,and so were protonate ions and multistage fragment ions.Conclusion: The methomyl metabolite in the rat plasma was S-methyl-N-hydroxythioacetamidate.
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<p><b>OBJECTIVE</b>To investigate telomerase gene expression in precancerous mammary lesion, such as atypical ductal hyperplasia and breast cancer and to study the relationship between expression and malignant transformation.</p><p><b>METHODS</b>Expression of human telomerase genes (hTR) and human reverse transcriptase gene (hTRT) in 76 cases of mammary tissue was evaluated using in situ hybridization and included 50 cases of mammary hyperplasia, 6 of which were benign hyperplasia, 9 were mild atypical hyperplasia, 12 were moderate atypical hyperplasia, 23 were severe atypical hyperplasia and 26 were mammary cancer.</p><p><b>RESULTS</b>The expressions of hTR and hTRT mRNA were much weaker or negative in benign hyperplasia (16.6%, 0), weak to mild moderate in atypical hyperplasia (22.2%, 11.1%, 33.3%, 25.0%), strong in severe atypical hyperplasia (60.9%, 52.1%), and significantly strong in mammary cancer (88.5%, 80.8%). The difference between mild-moderate atypical hyperplasia, invasive ductal carcinoma and severe atypical hyperplasia was significant (P < 0.05) and the difference between severe atypical hyperplasia and intraductal carcinoma was not significant (P > 0.05).</p><p><b>CONCLUSION</b>Telomerase genes (hTR and hTRT) expressions are related to the transformation of atypical hyperplasia. Activated telomerase may play a role in mammary cancer development.</p>
Subject(s)
Female , Humans , Breast , Metabolism , Pathology , Breast Neoplasms , Genetics , Pathology , DNA-Binding Proteins , Gene Expression , Precancerous Conditions , Genetics , Pathology , RNA , Genetics , Physiology , RNA, Messenger , Telomerase , Genetics , PhysiologyABSTRACT
<p><b>OBJECTIVE</b>To investigate the relationship of telomerase genes and the malignant transformation of atypical mammary ductal hyperplasia.</p><p><b>METHODS</b>Telomerase genes hTR and hTRT in 50 cases of mammary hyperplasia (the cases included 6 benign hyperplasia, 9 mild atypical hyperplasia, 12 medium atypical hyperplasia, 23 severe atypical hyperplasia) and 26 cases of breast carcinoma were detected by in situ hybridization.</p><p><b>RESULTS</b>The expression of hTR and hTRT mRNA were weak or negative in benign hyperplasia (1/6, 0), weaker in mild-moderate atypical hyperplasia (2/9, 1/9, 4/12, and 3/12), strong in severe atypical hyperplasia (14/23, 60.9% and 12/23, 52.1%), while very strong expression (23/26, 88.5% and 21/25, 80.8%) in carcinoma of the breast. The difference between mild-moderate atypical hyperplasia, invasive ductal carcinoma and severe atypical hyperplasia was significant (P < 0.05) and the difference between severe atypital hyperplasia and intraductal carcinoma was not significant (P > 0.05).</p><p><b>CONCLUSIONS</b>Telmerase genes (hTR, hTRT) expression is closely related to the malignant transformation of atypical hyperplasia. The reactivated telomerase may play a crucial role in the development of breast cancer.</p>