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Decabromodiphenyl ether (BDE-209), a major component of brominated flame retardants, has been detected in considerable amounts in the soil. Given that BDE-209 is toxic, ubiquitous, and persistent, it may cause toxic effects on vegetables planted in contaminated soil. In this study, Chinese cabbage seedlings cultivated in the soil contaminated by BDE-209 (5 - 20 mg kg-1) for 60 d were investigated to evaluate the phytotoxicity of BDE-209 in terms of growth, physiological responses, photosynthetic function, and antioxidant capacity. The results showed that BDE-209-induced phytotoxicity was reflected in the growth suppression, the decrease of chlorophyll content and soluble protein content, and especially in the reduced photosynthetic parameters (net photosynthetic rate and stomatal conductance). BDE- 209 showed direct toxicities to plasma membranes causing their elevated permeability. In addition, BDE-209 induced the overproduction of reactive oxygen species (ROS), membrane lipid peroxidation and protein carbonylation, manifesting in the increased content of O2 •-, H2O2, malondialdehyde, and carbonyl. Chinese cabbage seedlings activated the antioxidant defence system (superoxide dismutase and peroxidase) to scavenge the ROS and counter-balance the oxidative stress caused by BDE-209, while the toxicity could not be effectively alleviated. Our study will provide valuable information for further understanding of the phytotoxicity of polybrominated diphenyl ethers. [ABSTRACT FROM AUTHOR]

Decabromodiphenyl ether (BDE-209), a major component of brominated flame retardants, has been detected in considerable amounts in the soil. Given that BDE-209 is toxic, ubiquitous, and persistent, it may cause toxic effects on vegetables planted in contaminated soil. In this study, Chinese cabbage seedlings cultivated in the soil contaminated by BDE-209 (5 - 20 mg kg-1) for 60 d were investigated to evaluate the phytotoxicity of BDE-209 in terms of growth, physiological responses, photosynthetic function, and antioxidant capacity. The results showed that BDE-209-induced phytotoxicity was reflected in the growth suppression, the decrease of chlorophyll content and soluble protein content, and especially in the reduced photosynthetic parameters (net photosynthetic rate and stomatal conductance). BDE-209 showed direct toxicities to plasma membranes causing their elevated permeability. In addition, BDE-209 induced the overproduction of reactive oxygen species (ROS), membrane lipid peroxidation and protein carbonylation, manifesting in the increased content of O2 •-, H2O2, malondialdehyde, and carbonyl. Chinese cabbage seedlings activated the antioxidant defence system (superoxide dismutase and peroxidase) to scavenge the ROS and counter-balance the oxidative stress caused by BDE-209, while the toxicity could not be effectively alleviated. Our study will provide valuable information for further understanding of the phytotoxicity of polybrominated diphenyl ethers. [ABSTRACT FROM AUTHOR]

Objective: To evaluated the unplanned coverage dose to the internal mammary chain (IMC) in patient treated with postmastectomy radiotherapy (PMRT). Methods: One hundred and thirty eight patients with breast cancer receiving radiotherapy (RT) in our hospital were retrospectively analyzed. Patients were divided into three groups: three-dimensional conformal radiotherapy (3D-CRT) group, forward intensity-modulated radiotherapy (F-IMRT) group and inverse IMRT (I-IMRT) group. The IMC were contoured according to Radiation Therapy Oncology Group (RTOG) consensus, and were not include into the planning target volume (PTV). The incidental irradiation dose to IMC among the three groups and the first three intercostal spaces IMC (ICS-IMC 1-3) were all compared, and explored the relationship between the mean doses (Dmean) of IMC and the OARs (ipsilateral lung and heart). Results: The dose delivered to IMC showed no difference in CRT, F-IMRT and I-IMRT(33.80 Gy, 29.65 Gy and 32.95 Gy). And 10.42%, 2.04%, and 9.76% patients achieved ≥45 Gy when treated with CRT, F-IMRT and I-IMRT. For the IMC dose in the first three intercostal spaces (ICS1-3), there was no difference to the three treatment plannings. The Dmean, V(20), V(30), V(40) and V(50) of the ICS-IMC2 and ICS-IMC3 were all obviously superior than ICS-IMC1 for all these three plannings. Moderate positive correlation was founded between Dmean for IMC and Dmean for heart for left breast cancer patients underwent CRT ( r =0.338, P =0.01). Whereas for F-IMRT and I-IMRT groups, positive correlation were founded between Dmean for IMC and Dmean and V(20) for ipsilateral lung for all patients (F-IMRT: r =0.366, P =0.010; r =0.318, P =0.026; I-IMRT: r =0.427, P =0.005; r =0.411, P =0.008). Conclusions: In 3D-CRT, F-IMRT and I-IMRT planning methods, partial patients get IMC irradiated doses that could achieve therapeutic doses. Compared with 3D-CRT, F-IMRT and I-IMRT further reduced the dose of irradiated organs. However, there is no difference in the dose coverage of IMC for the three planned approaches when the IMC made an unplanned target.