1.Mutagenicity of Selenium and Lead and Antagonistic Effects of Selenium on Lead
Hua XIANG ; Jin CAI ; Mei WANG
Journal of Environment and Health 1993;0(03):-
ve To explore the mutagenicity of selenium and lead, the antagonistic effects of selenium on lead. Methods The ICR mice were orally perfused with sodium selenite (Na2SeO3) at different concentrations of 2.5,5.0 and 10 mg/kg and lead acetate [Pb(Ac)2] at different concentrations of 5,10 and 25 mg/kg jointly and con-tinuously for 3 days, and then the numbers of bone marrow polychromative erythrocytes were counted. Results The frequencies of micronucleus of mice only exposed to 10 mg/kg Na2SeO3, 10, 25 mg/kg Pb(Ac)2 respectively showed higher levels compared with those of control (P
2.Epidemiological analysis of brucellosis in Jinan city, Shandong province from 2002 to 2008
Hua-ru, XU ; Cai-yun, CHANG ; Qing-mei, SUI
Chinese Journal of Endemiology 2010;29(5):556-558
Objective To evaluate the epidemiological characteristics of brucellosis in Jinan city and to identify its cause in order to provide evidence for development of specific preventive strategies in the future.Methods Epidemic information of the disease and survey data of brucellosis cases from 2002 to 2008 in the Infectious and Endemic Disease Control Jinan Centre for Disease Control and Prevention were analyzed statistically.Results From 2002 to 2008, 52 cases were diagnosed as brucellosis, among which 39 cases from Zhangqiu city.The incidence rate ranged from 0.02 to 0.10 hundred thousandth from 2002 to 2006, and 0.25 and 0.26 hundred thousandth in 2007 and 2008, respectively. The disease was found each mouth throughout the year, marked with summer peak[38.46%(20/52)]. Patients increased year after year in summer and spring seasons(r = 0.92, P < 0.01) .The disease was most commonly found in 30 - 59 age group[69.23%(36/52)];men women incidence ratio was 1.67: 1.00;farmers accounting for 94.23%(49/52). There were 5 clusters of family outbreak brucellosis, involving 12 cases. Forty five patients contacted with sheep, accounting for 86.54% (45/52). Conclusions Brucellosis epidemic in Jinan is in an upward trend, mainly in summer and spring, elderly and middle-aged men farmers are the majority of patients. Zhangqiu of Jinan city is a key place for prevention and control of brucellosis;source of infection is not completely eliminated, exotic livestock have not been effectively quarantined, practitioners with weak sense of self-protection is the main reason of the epidemic rise.
3.The optimized cytokinesis-block assay for radiation-induced nucleoplasmic bridge
Hua ZHAO ; Tianjing CAI ; Xue LU ; Mei TIAN ; Qingjie LIU
Chinese Journal of Radiological Medicine and Protection 2021;41(3):178-182
Objective:To explore the feasibility of the optimized cytokinesis-block (CB) assay on radiation-induced nucleoplasmic bridge (NPB), and to provide a scientific basis for the application of NPB in biological dose estimation.Methods:Human peripheral blood in vitro was irradiated with 2 Gy 60Co γ-rays at a dose rate of 1 Gy/min (0 Gy control group). According to the culture time after irradiation, blood samples were divided into group 48, 56, 68 and 72 h. Cytochalasin-B (Cyt-B) with a concentration of 6 μg/ml was added into the samples at 28 h and harvested at 48, 56, 68 and 72 h after irradiation, respectively. On the other hand, the blood samples were treated with different concentration of Cyt-B i. e., 0.6, 1, 2, 6 and 10 μg/ml at the beginning of culture (0 h) and harvested at 68 h after irradiation. The proportion of mononucleated, binucleated and multinucleated cells, radiation-induced NPB and micronucleus (MN) frequencies were analyzed. Results:The nuclear division index (NDI) and proportion of binucleated cells at 2 Gy and 0 Gy had tendency of increasing with cell culture time. NPB frequencies (0.023 0-0.033 0/cell) and MN frequencies had no significantly difference ( P> 0.05). With the increase of Cyt-B concentration, NDI and the proportion of binucleated cells in group 2 Gy and 0 Gy also increased, but NPB frequencies (0.023 0-0.047 0/cell) had no significant difference ( P> 0.05). MN frequencies of group 10 μg/ml were significantly lower than that of group 6 μg/ml ( U=2.74, P< 0.01). Conclusions:Cell culture time and Cyt-B concentration had no significant influence on radiation-induced NPB frequencies, suggesting that NPB could be obtained by appropriately reducing cell culture time and Cyt-B could be added into blood samples at the beginning of culture. But this protocol reduced the number of cells for further analysis, and thus its feasibility for dose estimation still need to be studied.
5.Immunological Injury on the retina in streptozotocin-induced diabetic rats
Chun-Mei MENG ; Hua GAO ; Ming-Cai QIU ; Xin ZHANG ; Jin-Shi ZHANG ;
Chinese Journal of Endocrinology and Metabolism 2000;0(06):-
The depositions of immunoglobulins on the retina of diabetic rat were studied with immunohistochemistry,immunofluorecence and computer analysing system.In comparison with control group, depositions of IgG,IgA and IgM on the retina of diabetic rat induced by streptozotocin were significantly increased (all P<0.05 ).So the immunoglobulin depositions may contribute to the pathogenesis of diabetic retinopathy.
6.Association between Graves'disease and polymorphism of CTLA-4 gene in patients of the Han nationality in Tianjin area
Peng ZHANG ; Mei LI ; Yong ZHAO ; Meng-Hua YUAN ; Ming-Cai QIU ;
Chinese Journal of Endocrinology and Metabolism 1986;0(03):-
The polymorphism of (AT) repeat within the 3' untranslated region in exon 3 of CTLA-4 gene was evaluated by PCR-SSCP in 139 patients with Graves' disease (GD) and 110 normal subjects in Tianjin. The gene frequency of 106 bp in patients with GD was significantly increased than that in the control group (RR =1.992,P
7.APPLICATION OF TRICKLING FILTERS IN TREATMENT OF WASTEWATER FROM GAS-GENERATING WITH HEAVY OIL
Guo-Qu ZENG ; Mei-Ying XU ; Yong-Hua LUO ; Wen-Juan CAI ; Guo-Ping SUN ;
Microbiology 1992;0(04):-
A research combined trickling filter system and active sludge aeration system was applied in the treatment of industrial wastewater from gas-generating with heavy oil. The wastewater contained both high contents of NH+4-N and mixed hydrocarbons including various PAHs. Its BOD5/COD ratio was less than 0.3 and belongs to recalcitrant, toxic wastewater. The results showed a touch-growth biofilms system was formed on the porous packing material and it played a key role in the decrease of toxicity of the influent. It could also improve the biodegradability of the wastewater.
8.Study on the Biochemical Mechanism of Degrading Keratins by Streptomyces fradiae
Lin HUANG ; Zhi-Qiang XIONG ; Hua-Jing CAI ; Mei-Jin GUO ; Guo-Quan TU ;
Microbiology 1992;0(04):-
The biochemical mechanism of degrading keratins by S.fradiae var S-221 was primarily studied.The compounds (Na_ 2 SO_ 4 , Na_ 2 SO_ 3 and sulfdryl acohol), which respecitively enhance specific activity of keratinase, activate keratinase intensively and mainly act on the disulfide bonds reductase in the keratinase, Na_ 2 SO_ 3 activates intensively both disulfide bonds reductase and polypeptide hydrolytase at 0.01 mol/L, whereas Na_ 2 S_ 2 O_ 3 , which acts on the disulfide bonds reductase, inhibits keratinase.On the condition that substrate, keratins exists, S.fradiae var S-221 is induced to produce exo-keratinase, which is a multiproteinase, containing disulfide bonds reductase, which is a key enzyme degrading keratins, then, with polypeptidic, hydrolytase, graduately hydrolyzates denatured keratins into polypeptides, oligopeptides and free amino acids, so that keratins have been decomposed completely.Sulfur in the keratins was transferred into sulfhydryl compounds, H_ 2 S and sulfates in the course of keratinolysine.
9.Inhibitory effect of adenovirus mediated VEGF-siRNA on transplanted osteosarcoma in nude mice
You-Shui GAO ; Jiong MEI ; Tian-Lang TONG ; Mu HU ; Hua-Ming XUE ; Xuan-Song CAI ;
Chinese Journal of Cancer Biotherapy 1995;0(03):-
Objective: To investigate the inhibitory effect of adenovirus-mediated VEGF-siRNA on transplanted osteo- sarcoma in nude mice.Methods: VEGF-siRNA gene was cloned into the genome of replication-deficient adenovirus to construct Ad-VEGF-siRNA;the latter was then used to infect osteosarcoma MG63 cell line in vitro;and the expression of VEGF gene was detected by RT-PCR.Osteosarcoma transplantation model was established in nude mice;VEGF expression in tumor tissue was analyzed and the inhibitory effect on tumor growth and lung metastasis were also observed.Results: The recombinant adenovirus vector Ad-VEGF-siRNA was successfully constructed.In vivo and in vitro experiment both showed that Ad-VEGF-siRNA significantly downregulated VEGF expression in MG63 cells and transplanted tumor tissue. It was found that Ad-VEGF-siRNA significantly inhibited transplanted osteosarcoma growth(P
10.Effects of thiamine and riboflavin on H_2O_2-induced DNA oxidative damage
xiu-ling, LIU ; li, WANG ; chun-hua, JIANG ; wei-jun, CHEN ; mei-qin, CAI
Journal of Shanghai Jiaotong University(Medical Science) 2006;0(09):-
Objective To explore the effects of thiamine and riboflavin on H2O2-induced DNA oxidative damage in human umbilical vein endothelial cell line ECV304.Methods ECV304 cells were incubated with 10,100,500,1000 mg/L of thiamine or 20,100,300,500 nmol/L of riboflavin for 24 h,and then oxidative damage of cells were induced by 25 mol/L H2O2 for 30 min.DNA damage was detected with single cell gel electrophoresis(SCGE)assay.ECV304 cells incubated without H2O2,thiamine and riboflavin were served as negative controls,and those incubated with H2O2 and without thiamine and riboflavin were served as positive controls.Results H2O2 induced DNA damage,and the indices of percent of DNA damage cells,percent of tail DNA,tail length and Olive tail moment were increased.The indices of cells pretreated with 10,100,500 mg/L of thiamine or 20,100,300 nmol/L riboflavin were significantly decreased(P0.05).Conclusion Proper supplementation of thiamine and riboflavin may decrease H2O2-induced DNA oxidative damage,while excess thiamine and riboflavin supplementation may be harmful to DNA and enhance the susceptibility to H2O2 potentially.