1.The effect of 3'-meisoindigo on the function of splenocytes and thymocytes of C57BL/6 mouse
Hongbo GUO ; Haiyan HU ; Zhaoyang SONG ; Lan DENG ; Meixia ZHANG
Chinese Journal of Tissue Engineering Research 2008;12(31):6173-6176
BACKGROUND: The effect of Chinese traditional medicine 3'-meisoindigo as well as indimbin derivatives on normal immunocytes is less reported while it is used for antitumor.OBJECTIVE: To investigate the effect of 3'-meisoindigo on the proliferation of the splenocytes and thymocytes of C56BL/6 mouse.DESIGN, TIME AND SETTING: The randomized cytopathology observation was performed between August 2007 and January 2008 at Zhujiang Hospital of Southern Medical University, Guangzhou, Guangdong Province, China.MATERIALS: C57BL/6 mice, clean, male, 6-8 weeks old, weighing (20±2) g.METHODS: The thymus gland and the spleen of C57BL/6 mice were ground to get the single-cell suspension and cells were treated by 5, 10, 15, 20 and 25 μ mol/L 3'-meisoindigo,respectively. Cells without any drug treatment were used as blank control and cells treated by concanavalin A were used as positive control.MAIN OUTCOME MEASURES: Proliferation of splenocytes and thymocytes detected using MTT method; IL-12 activity in culture supematant detected using ELISA method; the cell cycle, apoptosis rate, cell death rate and intracellular reactive oxygen species level detected using flow cytometry; the mRNA level of bcl-2 and cdk2 detected using reverse transcription-polymerase chain reaction; the expression rate of Bcl-2, CDK2 and Bax detected using fluorescence microscope.RESULTS: After treating for 24 hours, 15, 20 and 25 μ mol/L 3'-meisoindigo can significantly inhibit the proliferation of thymocytes and splenocytes (P < 0.05) and the inhibition was dose-dependent and time-dependent. Cells resumed proliferation after removing the 3'-meisoindigo, although they had been treated by 25 μ mol/L 3'-meisoindigo for 72 hours. The secretion of IL-12 was markedly reduced in all 3'-meisoindigo groups versus control groups at each time point (P < 0.05). 15 μ mol/L 3'-meisoindigo could decrease the mRNA expression level of apoptosis-related protein bcl-2 and cyclin cdk2 gene, decrease the expression level of BCL-2 protein and CDK protein, increase Bax expression level, decrease Bcl-2/Bax ratio markedly and started apoptosis.15 μ mol/L 3'-meisoindigo arrested cells in the G2/M stage of the thymocytes and splenocytes, and intracellular reactive oxygen species level elevated dose-dependently and time-dependently.CONCLUSION: In certain concentration range, 3'-meisoindigo can reversibly inhibit the proliferation of thymocytes and splenocytes of C57BL/6 mouse and can inhibit IL-12 secretion in parallel, and start apoptosis.
2.Effects of cucurbitacin B on cell proliferation and apoptosis in Hep-2 cells.
Tingyan LIU ; Meixia ZHANG ; Yihui DENG ; Hongliang ZHANG ; Chunyan SUN ; Xiaolin YANG ; Wenyue JI
Journal of Clinical Otorhinolaryngology Head and Neck Surgery 2008;22(9):403-407
OBJECTIVE:
To investigate the mechanism underlying the anticancer activity of cucurbitacin B on human laryngeal cancer.
METHOD:
Hep-2 cells were treated with different concentrations of cucurbitacin B for different time. MTT assay was used to evaluate cell proliferation. Flow cytometry with PI staining and fluorescent microscopy with Hoechst 33258 staining were used to estimate cell cycle distribution and cell apoptosis. Expression of p-STAT3, cyclin B1 and Bcl-2 proteins was evaluated by Western blot assay. In vivo inhibitory effects of cucurbitacin B on tumor growth was evaluated in a nude mouse xenograft model.
RESULT:
Cucurbitacin B inhibited cellular proliferation in a dose and time dependent manner (P <0.05 or 0.01). Flow cytometry analysis showed that treatment with cucurbitacin B resulted in accumulation of cells at the G2/M phase of the cell cycle and cell apoptosis in a dose and time dependent manner (P <0.05 or P <0.01). Marked morphological changes of cell apoptosis including condensation of chromatin, nuclear fragmentation and apoptotic bodies were observed clearly by Hoechst 33258 staining. Western blot analysis demonstrated that the expression of p-STAT3, cyclin B1 and Bcl-2 proteins was suppressed significantly. In vivo studies showed that the inhibitory rates on laryngeal squamous carcinoma xenograft model were 32.43%, 43.24% and 70.27% for lower, moderate and higher dosage group, respectively.
CONCLUSION
Cucurbitacin B inhibited cell proliferation and induced apoptosis of Hep-2 cells by suppressing STAT3 signal pathway, down regulating the expression of cyclin B1 and Bcl-2 proteins.
Animals
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Apoptosis
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drug effects
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Cell Cycle
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drug effects
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Cell Line, Tumor
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Cell Proliferation
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drug effects
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Cyclin B1
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metabolism
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Gene Expression Regulation, Neoplastic
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Humans
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Mice
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Mice, Inbred BALB C
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Mice, Nude
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Proto-Oncogene Proteins c-bcl-2
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metabolism
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STAT3 Transcription Factor
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metabolism
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Triterpenes
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pharmacology
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Xenograft Model Antitumor Assays
3.Epidemiological survey and analysis on an outbreak of gastroenteritis due to water contamination.
ZhiCong YANG ; XinWei WU ; TieGang LI ; MeiXia LI ; Yi ZHONG ; YuFei LIU ; Zhiai DENG ; Biao DI ; Cong HUANG ; HuiYing LIANG ; Ming WANG
Biomedical and Environmental Sciences 2011;24(3):275-283
OBJECTIVETo document the investigation and control of an outbreak of gastroenteritis in City G, South China, and provide a reference for preventing future outbreaks.
METHODSAn ambispective cohort study was designed. Attack rate (AR) and relative risks (RR) were calculated to identify the causes of gastroenteritis. Investigations using questionnaires included personal interviews with patients and doctors, reviews of medical records, laboratory examinations of fecal specimens and continuous hygiene monitoring of water samples from the waterworks.
RESULTSOverall, 427/71534 (AR=5.97%) cases were identified between October 31 and November 12 2010. Geographic distribution was highly localized, with 80% of cases occurring in the areas supplied by waterworks-A. Consumption of water provided solely by waterworks-A was found to be associated with illness (RR=8.20, 95 CI%:6.12-10.99) compared with that from waterworks-B. Microbiological analyses confirmed the presence of Norovirus in six of eight fecal samples from symptomatic patients, two water samples from waterworks-A and two sewage samples. After taking effective measures, the hygienic indices of waterworks-A met health criteria again on November 9 and no cases were reported 3 days later.
CONCLUSIONThe outbreak reported here was caused by drinking tap water contaminated with sewage at the source. Early identification of possible contamination sources and awareness of changes that might negatively impact water quality are important preventive measures to protect public health.
Adolescent ; Adult ; Aged ; Child ; Child, Preschool ; Disease Outbreaks ; Female ; Gastroenteritis ; epidemiology ; etiology ; Humans ; Infant ; Male ; Middle Aged ; Water Pollution ; adverse effects ; Young Adult
4.Identification of in vivo-induced antigen Tp0462 of Treponema pallidum and evaluation of its application to serodiagnosis of syphilis
Wen LIU ; Meixia DENG ; Xiaohong ZHANG ; Tie ZHAO ; Xi LUO ; Feijun ZHAO ; Weiguo YIN
Chinese Journal of Dermatology 2018;51(5):352-357
Objective To screen and identify the in vivo-induced antigen Tp0462 of Treponema pallidum (Tp),and to evaluate its value for clinical serological diagnosis of syphilis.Methods Genomewide DNA was extracted from the Tp Nichols strain,and polymerase chain reaction (PCR) was performed to amplify the Tp0462 gene.A recombinant plasmid pET30a (+)-Tp0462 was constructed and transfected into the Escherichia coli (E.coli) Rosetta (DE3) strain.Recombinant protein Tp0462 was abundantly expressed,purified and identified.A total of 18 New Zealand rabbits were randomly and equally divided into 3 groups:viable Tp-incubating group incubated with viable Tp in the testes,inactived Tp-incubating group incubated with ultraviolet irradiation-killed Tp in the testes,and control group receiving no treatment.After incubation,blood samples were collected at different time points,and the sera were isolated for identification of characteristics of in vivo-induced antigen Tp0462.Enzyme-linked immunosorbent assay for Tp0462 (Tp0462-ELISA),Treponema pallidum particle agglutination assay (TPPA),preliminary syphilis screening ELISA and rapid plasma reagin (RPR) card test were applied in 336 clinical serum samples from patients with syphilis,so as to preliminarily evaluate the value of Tp0462 for the diagnosis of syphilis.Results The optimum conditions for expression of the recombinant plasmid Tp0462-pET30a(+) in E.coli Rosetta (DE3) strains were the treatment with 0.5 mmol/L isopropyl thiogalactoside (IPTG) on a shaker at 180 rpm for 4 hours.In the viable Tp-incubating group,the serum level of specific anti-Tp0462 antibody sharply increased from week 2,and went steady after week 5.However,the specific anti-Tp0462 antibody maintained a low level in the inactived Tp-incubating group and the control group.The viable Tp-incubating group showed a significantly higher level of specific anti-Tp0462 antibody compared with the inactived Tp-incubating group and the control group (both P < 0.05),while no significant difference was observed between the inactived Tp-incubating group and the control group (P =0.256).The level of anti-Tp92 antibody was significantly higher in the viable Tp-incubating group and the inactived Tp-incubating group than in the control group (P < 0.05),while there was no significant difference between the viable Tp-incubating group and the inactived Tp-incubating group (P =0.127).Compared with TPPA,the sensitivity,specificity,consistency rate and area under the curve (AUC) of Tp0462-ELISA for the diagnosis of syphilis were 91.7%,98.8%,95.2% and 0.997 respectively.Tp0462-ELISA was consistent to preliminary syphilis screening ELISA and RPR with a Kappa coefficient of 0.846 and 0.293,respectively.Conclusion Tp0462-ELISA has shown evidently higher sensitivity and specificity in the serodiagnosis of syphilis,and Tp0462 can serve as promising antigens for the diagnosis of syphilis.