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Per- and polyfluoroalkyl substances (PFASs) were detected in the atmosphere of a source region in Tianjin, China. Fluorotelomer alcohols (FTOHs) were the dominant neutral PFASs in the atmosphere with total concentrations of 93.6-131 pg/m 3 and 8:2 FTOH contributing the most, whereas perfluorooctane sulfonamide derivatives (PFOSAs) were two magnitudes lower or undetected. In comparison, ionic PFASs (perfluoroalkyl carboxyl acids (PFCAs)) in the atmosphere were detected at similar or even higher levels. At wastewater treatment plants (WWTPs), the air over influent was found with higher levels of FTOHs than over aeration tank and effluent; whereas in the air over the aeration tank, the concentrations of PFOSAs and nonvolatile ionic PFASs substantially increased, suggesting a possible direct release of ionic PFASs to the atmosphere besides the atmospheric conversion from volatile precursors. In the air phase, a low proportion (1-5%) of PFCAs was subjected to dry deposition in the source region. Interestingly, the dry-deposition-to-bulk-air ratios of PFCA analogues were the lowest at medium chain lengths (C8 and C9) and increased with either shorter or longer chain length. The extraordinary affinity of shorter-chain PFCAs (C6-C7) to particles was presumed to be due to their smaller molecular size favoring the interactions between the carboxyl head groups and specific sorption sites on particulate matter. [ABSTRACT FROM AUTHOR]

State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China (People's Republic) Acute myeloid leukaemia (AML) is an aggressive hematologic neoplasm with distinct molecular and genetic features which is characterized by differentiation blockade and uncontrolled proliferation of malignant clones of immature myeloid cells. The growth arrest and DNA-damage induced 45 (GADD45) family protein GADD45g, has been shown to mediate DNA repair, cell cycle, senescence and apoptosis in response to various physiological and environmental stressors. Altered expression of GADD45g has been observed in multiple types of solid tumors, the function of GADD45g in hematopoietic malignancies remains almost completely unknown. Here, we found that GADD45g expression was preferentially silenced in AML, especially in AML with MLL rearrangements and FLT3-ITD mutations, and reduced expression of GADD45g correlates with poor prognosis in AML patients. Ectopic expression of GADD45g suppresses leukemic growth, induced apoptosis, senescence and differentiation of AML cells in vitro and in vivo. What's more, GADD45g caused downregulation of DNA repair proteins, resulting in inhibition of DNA double-strand break repair pathways and leading to DNA damage accumulation in AML cells. Moreover, GADD45g is epigenetically silenced in AML by both promoter DNA methylation and histone deacetylation, while the HDACi is more powerful. Exogenous expression of FLT3-ITD and MLL-AF9 repress GADD45G expression in AML, and the expression of GADD45G could be significantly induced by the small-molecule inhibitors FLT3 TKI or BRD4i target FLT3 or MLL respectively. Furthermore, the combination of HDACi and FLT3 TKI or BRD4i exerted a synergistic effect against FLT3-ITD+ or MLL-rearranged AML, respectively. These findings suggest that GADD45G may act as a tumor suppressor in AML and provide a novel and promising therapeutic target for AML. [ABSTRACT FROM AUTHOR]

Abstract: A nationwide investigation on the occurrence of artificial sweeteners (ASs) was conducted by collecting 98 paired outdoor dust and soil samples from mainland China. The ASs were widely detected in Chinese atmospheric dry deposition and soil samples, at concentrations up to 6450 and 1280ng/g, respectively. To give a picture on AS distribution and source in the whole environment, the concentrations and seasonal variations of ASs in Tianjin were studied, including atmosphere, soil, and water samples. The AS levels were significantly higher in Haihe river at TJW (a sampling site in central city) in winter, while no obviously seasonal trends were obtained at BYL (close to a AS factory) and the site at a wastewater treatment plant. Saccharin, cyclamate, and acesulfame were the dominant ASs in both gas and particulate phase, with concentrations varying from 0.02 to 1940pg/m3. Generally, gas phase concentrations of the ASs were relatively higher in summer, while opposite results were acquired for particulate phase. Wet and dry deposition fluxes were calculated based on the measured AS levels. The results indicated that both wet and dry deposition could efficiently remove ASs in the atmosphere and act as important pollutant sources for the ASs in surface environment. [Copyright &y& Elsevier]