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

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.

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.

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.

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

Background The condition of the sclera is associated with many ocular diseases.The measurement of human scleral thickness in vivo is helpful for us to understand the features of the sclera and related diseases.Objective The present study was to measure the anterior sclera thickness(AST) in patients with senile cataract and to analyze the relationship among AST and other associated ocular parameters.Methods This study was approved by the Ethic Commission of First Hospital of Peking University.Written informed consent was obtained from each individual prior to examination.One hundred and five senile cataract patients were recruited in this study.Central corneal thickness (CCT),corneal curvature (CCV) and axial length were measured using ultrasonic pachymeter,keratometer,and A-scan unit,respectively.The AST was measured at 2 mm posterior to the scleral spur in the temporal meridian using ultrasound biomicroscope (UBM).The differences of CCT,CCV,ocular axial length and AST between bilateral eyes and the different sexes were compared by the Paired test and independent sample t test.The correlations among various parameters were assessed by the Pearson linear correlation analysis.The differences of CCT and AST among different axial length groups were evaluated by one-way ANOVA.Results No significant differences were found in the CCT,CCV,axial length and AST between bilateral eyes (t =0.584,P =0.561 ; t =1.161,P =0.248 ; t =0.140,P =0.889 ; t =0.342,P =0.773).Temporal AST at 2 mm posterior to the sclera spur was (0.589 ±0.051)mm in the right eyes.An insignificant decline in CCT was found in the male group compared with the female group (right eyes:t =0.469,P =0.641 ; left eyes:t =0.465,P =0.643).However,compared with the female group,the increase of axial length,reduction of the mean CCV value and enhancement of the mean AST were observed(right eyes:all P＜0.01 ;left eyes:all P＜0.01).CCV showed a negative correlation with ocular axial length (r =-0.50,P＜0.01),but no significant correlation was found among age,CCT,ocular axial length and AST(P＞0.05).No remarkable differences were found in CCT and AST among the various axial length groups (CCT:F =0.998,P=0.372;AST:F=1.919,P=0.383).Conclusions In senile cataract patients,correlation is not found between AST and CCT;the increase of axial length is not associated with the thinning of the eyeball wall to a certain extent.Differences exist in some ocular parameters between different sexes.

Background A close relation between sclera thickness and glaucoma has been determined.Clinical features vary in different types of glaucoma patients,which hints that the scleral thickness might be distinct among these patients.Objective The aim of this study was to investigate the differences of central corneal thickness(CCT),anterior scleral thickness(AST) and axial length in glaucomatous patients.Methods This study was approved by the Ethic Commission of First Hospital of Peking University.Written informed consent was obtained from each individual prior to the examination.A retrospective descriptive study was designed.One hundred and sixty consecutive patients were recruited from March,2009 to November,2010 in First Hospital of Peking University,including 35 eyes with primary angle closure glaucoma(PACG) (35 cases),34 eyes with primary open-angle glaucoma POAG) (34 cases),37 eyes with normal tension glaucoma(NTG) (37 cases)and 17 eyes of ocular hypertension OHT) (17 cases).Thirty-seven eyes of 37 subjects with incipient cataract served as the control group.CCT and ocular axial length were measured with ultrasonic pachymeter and A-scan unit,respectively,and AST at the temporal quadrant 2 mm posterior to the scleral spur was measured by ultrasonic biomicroscopy (UBM).The measuring parameters among different groups were compared by analysis of covariance,and the correlations of AST,CCT with ocular axial length were analyzed using Pearson linear correlation and linear regression.The differences and correlation of CCT,AST and AL among five groups were analyzed.Results The CCT values in PACG group,POAG group,NTG group,OHT group and control group were (535.54 ± 5.20),(550.47 ± 5.28),(521.61 ± 5.07),(575.75 ± 7.76) and (535.06± 5.06) μm,respectively,showing a significant difference among them (F =9.560,P =0.000),and the CCT value of OHT group was increased in comparison with POAG group,PACG group,NTG group and control group(all P =0.000).The CCT of the POAG group was thicker than that in the PACG group,NTG group and control group(P=0.046,0.000,0.040).No significant difference was found in CCT among NTG group,PACG group and control group(P=0.950,0.060).The AST values of PACG group,POAG group,NTG group,OHT group and control group were(0.593±0.050),(0.600±0.050),(0.592-±0.060),(0.610-±0.060) and(0.604±0.060) mm,respectively,showing a insignificant difference among them (F =0.700,P =0.590).The axial length in the patients with PACG was shorter than that of the POAG group,NTG group,OHT group and control group (all P =0.000).The Pearson correlation analysis showed significantly positive correlation between CCT and AST in POAG group and NTG group(r=0.445,P=0.008;r=0.400,P=0.014).Conclusions This study confirms that there is dissimilarity in CCT but not in AST among different types of glaucomatous patients.The changes of CCT and AST are consistent in POAG and NTG patients.

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.

Acupuncture Points ; Adult ; Aged ; Female ; Humans ; Injections ; Intervertebral Disc Displacement ; drug therapy ; Lumbar Vertebrae ; drug effects ; Male ; Middle Aged ; Ozone ; administration & dosage

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.