ABSTRACT
<p><b>OBJECTIVE</b>To study 17β-estradiol (E2), ethinylestradiol (EE2), estriol (E3), estrone (E1) on MCF-7 proliferation effects, and compare the effects of independent action (IA) model with concentration addition (CA) model in assessing the combined effects of estrogen.</p><p><b>METHODS</b>The combinations of E2 + EE2, E2 + E3 and E2 + E1 were chosen and the cellular proliferation effects were examined by MTT assay.</p><p><b>RESULTS</b>The maximum proliferation effects at dose of 10⁻⁹ mol/L was 325.48% for E2, 330.34% for EE2, 255.22% for E3, and 199.61% for E1. In the E2 + EE2, E2 + E3, E2 + E1 groups, the results of IA model analysis were very close to the experimental results. The IA model tend to overestimated the experimental results, while the CA model often underestimated the experimental results. In the EC (E2, 30) + C (EE2, 70) group, the results exceed the maximum estrogen effects of E2, while in other groups, the results were lower.</p><p><b>CONCLUSIONS</b>The estrogenic effects of the four tested substances from high to low efficiency were that: EE2 > E2 > E3 > E1. The effect of IA model in predicting the combined effects of binary mixture was better than CA model. A small proportion of binary mixture showed synergy.</p>
Subject(s)
Female , Humans , Cell Line, Tumor , Cell Proliferation , Estradiol , Pharmacology , Estriol , Pharmacology , Estrogens , Pharmacology , Estrone , Pharmacology , Ethinyl Estradiol , PharmacologyABSTRACT
<p><b>OBJECTIVE</b>To observe the effect of chronic lead contaminant on protein expression of protein kinase (PKC) and calmodulin (CaM) in hippocampus of baby-rats.</p><p><b>METHODS</b>The Wistar pregnant rats were randomly divided into 3 groups fed with distilled water and lead-contained water (0.2% and 1.0% lead acetate) respectively. The lead exposure period ranged from the 0 day of pregnancy to the offspring weaned. Then the baby-rats were fed with lead water the same as their mothers. Pups were killed at postnatal day 8 and 50 respectively. Atomic absorption spectrometry was used to determine lead content of rats' brain. Western-blotting was used to observe protein expression of PKC and CaM in hippocampus of baby-rats.</p><p><b>RESULTS</b>The brain lead content of test groups was much higher than that of the control group in the same growth period (P < 0.01). The content of brain lead in rats of postnatal day 50 was significantly higher than that of rats of postnatal day 8 (P < 0.01). Compared with control group, PKC and CaM protein expressions of chronic lead exposure baby-rats in the hippocampus were down trend (P < 0.05).</p><p><b>CONCLUSION</b>The decrease of PKC and CaM protein expression level in hippocampus might be one of the molecular mechanisms of lead induced impairment of learning and memory.</p>
Subject(s)
Animals , Female , Male , Pregnancy , Rats , Calmodulin , Metabolism , Hippocampus , Metabolism , Lead , Toxicity , Prenatal Exposure Delayed Effects , Protein Kinase C , Metabolism , Rats, WistarABSTRACT
<p><b>OBJECTIVE</b>To study the genotoxicity of components of diesel engine exhausts with ethanol-diesel blending fuel. To provide scientific arguments to find more economical and less polluted fuels.</p><p><b>METHODS</b>Ames test, comet assay and GC-MS technique were used to test the genotoxicity and 16 kinds of PAHs on diesel engine exhausts with different proportions of ethanol (E0, E5, E10, E20).</p><p><b>RESULTS</b>Both Ames test and comet assay were positive. It shows that diesel engine exhausts can lead to mutation and DNA damage, especially in pure diesel oil. But the content of 16 kinds of PAHs and DNA damage level decreased in exhausts of E5. With the increase of ethanol proportion in diesel oil, the content of 16 kinds of PAHs and DNA damage level increased.</p><p><b>CONCLUSION</b>Compared with pure diesel oil and high proportion of ethanol fuel, E5 can reduce the genotoxicity and the brake specific exhausts of PAHs.</p>
Subject(s)
Air Pollutants , Toxicity , Air Pollution , Carbon Monoxide , Comet Assay , DNA Damage , Ethanol , Toxicity , Gasoline , Toxicity , Mutagenicity Tests , Particulate Matter , Vehicle Emissions , ToxicityABSTRACT
Objective To investigate the effects of repeated exposure by inhalation to several concentrations of formaldehyde 5 hours/day 7 consecutive days on the content of neurotransmitters in the brain of adult female BALB/c mouse. Methods The 24 mice were randomly divided into 3 groups(groups A to C) 8 in each and exposed respectively to formaldehyde of 0.02-0.07 mg/m3 controls 0.99-1.2 mg/m3(3 m2 plywood/m3 room)and 3.44-3.63 mg/m3(10 m2 plywood/m3 room). After sacrifice the brain were excised and the neurotransmitters were examined. Results Asp、NE、Glu、E and Ach in animals of the exposed groups were significantly decreased but GABA was increased. Conclusion Exposure of formaldehyde escaped from plywood may result in neurochemical change such as Asp NE GluE Ach and GABA in the brain of mouse.