Objective To test the toxicity of genetically engineered strain R32 released to the environment.Methods Acute,chronic and cumulative toxicity test on mice,micronucleus assay of mice bone marrow cell and mice sperm malformation test were conducted to assess the toxicity of strain R32.Results R32 did not cause acute,chronic,cumulative and genetical toxic effect on mice before it absorbed heavy metal chromium.Although the mice bone marrow micronucleus frequency increased and some cumulative toxic effect emerged after R32 absorbed chromium,it did not cause acute and chronic toxicity effect on mice and mice sperm malformation rate did not increase neither.Furthermore,whether R32 absorbed heavy metal chromium or not,the effect of its secretion was not significant in all experiments compared with the control.Conclusion R32 can not cause toxic effect on mice before it absorbed chromium.Whether R32 absorbed chromium or not,the effect of its secretion was not significant in all toxicological experiments conducted in the present paper.Large content of R32 may cause some cumulative toxic effect in mice after it absorbed chromium.

Objective To investigate air bacteria pollution and the rule of microbes spread in some markets in Guangzhou, aiming at prevention and forecast airborne pathogenic microbes. Bacteria and Staphylococcus aureus were collected to provide reference on evaluation and of the spread of through the air in public. Methods Gravity exposure of microbial media plates was used to sample the airborne bacteria in eight different markets in Guangzhou on a given day, from 2003 to 2005. The simulated experiment in the laboratory was conducted based on the results of natural sampling stations. Results Samples taken at different times showed wide variations with quantities of airborne bacteria (total count) and Staphylococcus aureus ranged from 95 to 1.5?104 cfu per petri dish and from 2 to 1.2?104 cfu per petri dish respectively. Movement of airborne bacteria in the market obeyed quadratic equation pattern. The spread distance of airborne bacteria was among 24 to 26 meters. Maximum airborne bacteria were detected from 17:00 o'clock to 19:00 o'clock in a day. Conclusion The count of market airborne bacteria is markedly more than the limits stipulated in the related national standard GB 9670-1996. Live fowls sold in the markets are the main carriers of bacteria and the potential pollution resource of pathogenic bacteria.

Objective To observe the various influence of Imipenem/Cilastatin(IPM) and Cefoperazone(CPZ) on Gram-negative bacterial endotoxin release in severely burned patients.Methods Patients were divided into IPM group and CPZ group randomly. The bacterial cultures and microbial drug-sensitivities of burn wound swabs and subeschar tissues were performed on the 1st and 3rd day, At the same time, the levels of LPS in plasma were detected in seven burned patients administrated with IPM and six with CPZ at the time 0?2?4?12?24?48?72h of antibiotics administration.Results Patients were infected by Gram-negative bacterial. The counting of bacteria in subeschar tissues decreased 10~100 times after the administration of antibiotics 3 days; Plasma LPS levels elevated to the peak value at 2h after infusion of IPM or CPZ , and then showed significant decrease. The magnitude of increased LPS in CPZ group was higher than that in IPM group; The LPS levels of 72h were lower significantly than that of 0h.Conclusion IPM and CPZ could effectively control Gram-negative bacterial infection and induce the releases of LPS from bacteria, of which the former induced less LPS release than the latter; The levels of LPS came down with the decreasing of bacterial counting.

Insect viruses are attractive as biological control agents and could be a feasible alternative to chemical insecticides in the management of insect infestations. This review describes recent advances in the development of wild-type and genetically modified viruses as insecticides. A new strategy of application of insect viruses in China is reviewed. Also, the assessment of biosafety of genetically modified Helicoverpa armigera Nucleopolyhedovirus (HearNPV) is emphasized as a case-study.

Adult ; Female ; Health Knowledge, Attitudes, Practice ; Health Promotion ; Humans ; Lead ; Male ; Middle Aged ; Occupational Exposure ; prevention & control ; Occupational Health ; Occupational Health Services ; Stearates ; Young Adult

The purpose of risk assessment is to evaluate the permissible exposure level under specific risk factors.To extrapolate the human acceptable daily intake (ADI) and/or reference dose (RfD), the traditional method uses the no-observed-adverse-effect level ( NOAEL ) to quantify toxicity after being divided by uncertainty factor.There are many limitations with NOAEL method in safety evaluation,for it relies too much on experimental design.Benchmark dose ( BMD) approach is a more reliable method with many advantages.BMD approach and its analysis software, the advantages of BMD over NOAEL, the application and methodological perfection in risk assessment of long-team exposure toxicity are presented in this review.

The relationship of interleukin-4 (IL-4) C-33T and C-590T (C-589T) gene polymorphisms with allergic rhinitis was analyzed. Data about the case control studies of IL-4 gene promoter polymorphisms [C-33T and C-590T (C-589T)] and their association with allergic diseases and correlation between serum IL-4 levels and allergic rhinitis were retrieved. The Stata 12.0 statistical software was applied to analyze the correlation between IL-4 gene polymorphisms and allergic rhinitis. The meta-analysis result of TT/CC genotype of -590 (-589) polymorphism showed a significant association with allergic diseases [OR=1.93, 95% CI (1.61-2.31), P=0.00]. Meta-analysis of the TT+TC versus CC genotype of IL-4 C-33/T polymorphism revealed significant associations with allergic diseases [OR=3.23, 95% CI (1.13-9.25), P=0.03]. Meanwhile, there was a significant correlation between serum IL-4 levels and allergic rhinitis [OR=2.52, 95% CI=(1.80-3.23), P=0.00]. IL-4 gene -590 TT genotype may increase the risk of allergic rhinitis and the T allele mutation of -33 might be correlated with allergic rhinitis.

This study evaluated, over a 4-month study period, the amount of apical root resorption occurring in maxillary central incisors following their retraction when employing either micro-implant or J-hook headgear anchorage. The prospective randomised clinical trial was conducted in Orthodontic Clinic, College of Stomatology, China from 2008-2009. Subjects are patients requiring fixed appliances on waiting list (n=20). In female Han Chinese patients aged from 16-26 years, standardized periapical radiographs from 10 randomly assigned patients with maxillary protrusions comprising the micro-implant group, and from 10 similar patients comprising the J-hook headgear group, were assessed for maxillary central incisor apical root resorption. Measurements before and after orthodontic therapy were also obtained from lateral cephalometric radiographs to calculate incisor horizontal retraction and vertical intrusion distances. Estimated retraction force vectors were calculated in horizontal and vertical directions for both treatment groups. Data analysis employed t-tests and the Pearson correlation test, with α=0.05 for statistical significance. The results showed that when compared with the J-hook group, significantly more apical root resorption shortening of the maxillary central incisors was observed in the micro-implant group (1.27 mm difference, 95% CI=0.70-1.84, P<0.001), which was associated with a significantly larger retraction distance (P=0.004) and a smaller vertical force component (P<0.0001). We are led to conclude that continuous activation of the nickel-titanium coil springs used in the micro-implant group resulted in significantly more apical root resorption shortening and maxillary central incisor retraction than when intermittent J-hook retraction was employed. The employment of continuous duration orthodontic forces presents a risk for increased apical root resorption that requires careful radiographic monitoring.

0.05).The serum PICP of tubercular meningitis children after 4 neeks glucocorticoid therapy (108.85?46.13) ?g/L was significantly lower than that in control group((154.38)?47.98) ?g/L and glucocorticoid- pretreatment (152.99?44.78) ?g/L (P

0.05).We did not find any difference of the expression of fibronectin,laminin and type IV collagen in them.Expression of ICAM and VCAM were(56.4?14.8)% and(55.6?12.2)%,respectively,obviously higher than those in control group(P