Hahnlyng5634

9 ng/mL, 8 h, 69.4 ± 2.24 ng/mL) in mouse blood were found than those of TBMEHP (4 h, 17.2 ± 4.01 ng/mL, 8 h, 12.8 ± 3.20 ng/mL), indicating that TBB was more readily in vivo metabolized than TBPH. The in vivo metabolism of TBB and TBPH and the stronger toxicity of their metabolites underscore the potential risk through NBFR exposure and the importance of understanding NBFR metabolism process. PURPOSE To propose national diagnostic reference levels (DRLs) for radiotherapy (RT) computed tomography (CT) localization purposes, compare both CT units used in the largest RT department in the country and to compare gathered results with other published DRLs in order to discover any need of optimization. METHODS In total, 1631 patient data (time spend of 4 months) regarding sex, examination type, total dose-length product (DLP) and CTDIvol was collated on two CT units. Those simulation procedures account for more than 80 % of all simulation procedures performed nationwide. Then, total DLP and CTDIvol was calculated and mean, median and 3rd quartile for both units together were presented to determine national DRLs for simulation procedures. The same data was later compared between both units to discover any potential need for optimization. RESULTS 3rd quartile values of DLP for abdomen, breast, chest, head, head and neck, pelvis and spine were 1116.2, 606.6, 832.4, 1942.4, 969.2, 677.1 and 1042.4 mGy∙cm, respectively. 3rd quartile CTDIvol values for the same sequence of procedures were 18.7, 13.3, 19.2, 76.9, 22.6, 17.9 and 22.2 mGy, respectively. Among the two units, the mentioned dose values were on average significantly higher on one CT unit than on the other unit. CONCLUSIONS When comparing collected dose values with other studies, RT CT DRLs showed that radiation doses from our institution were similar or even lower. Some variations were found between both CT units in certain protocols, so exposure parameters should be reviewed and optimized. Mammalian cells have evolved multiple pathways to repair DNA double strand breaks (DSBs) and ensure genome stability. In addition to non-homologous end-joining (NHEJ) and homologous recombination (HR), cells evolved an error-prone repair pathway termed microhomology-mediated end joining (MMEJ). The mutagenic outcome of MMEJ derives from the activity of DNA polymerase theta (Polθ) - a multidomain enzyme that is minimally expressed in normal tissue but overexpressed in tumors. Polθ expression is particularly crucial for the proliferation of HR deficient cancer cells. As a result, this mutagenic repair emerged as an attractive target for cancer therapy, and inhibitors are currently in pre-clinical development. Here, we review the multifunctionality of this enigmatic polymerase, focusing on its role during DSB repair in mammalian cells and its impact on cancer genomes. Two typical polycyclic musks (PCMs), namely 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-(g)-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN), were determined in 63 surface water and 42 sediment samples collected from the North Canal River watershed, an urban catchment located in the megacity Beijing, China. Concentrations of HHCB and AHTN were 13.2 ng/L-395 ng/L and 2.98 ng/L-232 ng/L in surface water, while 4.10 ng/g-818 ng/g and 1.21 ng/g-731 ng/g in sediments. The results showed that PCM concentrations in the North Canal River watershed were at the high end when compared to that in other regions in China and worldwide. A watershed-wide annual mass budget showed that HHCB (∼150 kg/year) and AHTN (∼80 kg/year) mainly originated from urban wastewaters. Both PCMs were eliminated primarily by outflowing water (72 kg/year and 43 kg/year for HHCB and AHTN, respectively) and due to losses to the atmosphere (40 kg/year and 26 kg/year for HHCB and AHTN, respectively). An assessment of ecological risks posed by HHCB and AHTN to aquatic organisms in the North Canal River watershed was performed by using a tiered ecological risk assessment. The results showed that PCMs were unlikely to pose an ecological risk at the watershed scale (the probability of the incidence of adverse effect was less then 3.5% at the 99% protection level). However, according to the results from the risk quotient method, the tributaries draining wastewater effluents should be hotspots that warrant further research in future. Whereas there is broad consensus that smelting causes serious soil contamination during vanadium production, little is known about the vanadium content of soil near smelters and the associated health risk at continental scale. This study is the first to map the distribution of vanadium in farmland soil surrounding smelters throughout mainland China, and assess the associated health risk. Analysis of 76 samples indicated that the average vanadium content in such soil was 115.5 mg/kg - far higher than the 82 mg/kg background content in China (p  less then  0.05). Southwest China (198.0 mg/kg) and North China (158.3 mg/kg) possessed highest vanadium contents. Vanadium content was strongly related to longitude, altitude, and atmospheric temperature. The reducible fraction accounted for the largest percentages in vanadium speciation. The average Pollution Load Index for all samples was 1.51, denoting significant metal enrichment. The Children's hazard index was higher than unity, indicating elevated health risk. The relative contribution of vanadium to the total health risk ranged from 6.02% to 34.5%, while nickel and chromium were the two main contributors in most regions. This work may serve as a model providing an overview of continental vanadium contamination around smelters, and draw attention to their possible health risks. The objective of the present study was to investigate recent concentrations of perfluoroalkyl substances (PFASs) in white whales (Delphinapterus leucas) from Svalbard and compare them to concentrations found in white whales sampled from that same area 15 years ago. Plasma collected from live-captured white whales from two time periods (2013-2014, n = 9, and 1996-2001, n = 11) were analysed for 19 different PFASs. The 11 PFASs detected included seven C8-C14 perfluoroalkyl carboxylates (PFCAs) and three C6-C8 perfluoroalkyl sulfonates (PFSAs) as well as perfluorooctane sulfonamide (FOSA). Recent plasma concentrations (2013-2014) of the dominant PFAS in white whales, perfluorooctane sulfonate (PFOS; geometric mean = 22.8 ng/mL), was close to an order of magnitude lower than reported in polar bears (Ursus maritimus) from Svalbard. PFOS concentrations in white whales were about half the concentrations in harbour (Phoca vitulina) and ringed (Pusa hispida) seals, similar to hooded seals (Cystophora cristata) and higher than in walruses (Odobenus rosmarus) from that same area. From 1996 to 2001 to 2013-2014, plasma concentrations of PFOS decreased by 44%, whereas four C9-12 PFCAs and total PFCAs increased by 35-141%. These results follow a similar trend to what has been reported in other studies of Arctic marine mammals from Svalbard. The most dramatic change has been the decline of PFOS concentrations since 2000, corresponding to the production phase-out of PFOS and related compounds in many countries around the year 2000 and a global restriction on these substances in 2009. Still, the continued dominance of PFOS in white whales, and increasing concentration trends for several PFCAs, even though exposure is relatively low, calls for continued monitoring of concentrations of both PFCAs and PFSAs and investigation of biological effects. In order to determine the current levels, spatial distribution patterns, and potential pollution of trace elements (TEs) in the atmosphere of the Tibetan Plateau (TP), snow pit samples were collected in May 2016 from five TP glaciers Qiyi (QY), Hariqin (HRQ), Meikuang (MK), Yuzhufeng (YZF), and Xiaodongkemadi (XDKMD). Concentrations of 13 TEs (Al, Ba, Cd, Co, Cr, Cu, Fe, Li, Pb, Sb, Sr, U, and Zn) in the snow were measured. The spatial distribution patterns and depth profiles of TEs from the studies sites revealed that the influence of dust on TEs was more significant on the MK and YZF glaciers than on the QY, HRQ, and XDKMD glaciers. The spatial distributions of TE EFFe values differed from their concentrations, however. The enrichment factor (EF) values and concentrations of some TEs in the YZF, QY, and XDKMD glaciers revealed that the pollution levels of these elements were significantly lower than those found in previous research. Examination based on EFs, principal component analysis, as well as the calculated non-dust contributions of TEs, revealed that dust was the principal source for most TEs in all five glaciers, while biomass burning was another potential natural source for TEs in some glaciers, such as QY. In contrast, Cd, Ba, Sr, Cu, Pb, Zn, and Sb were occasionally affected by anthropogenic sources such as road traffic emissions, fossil fuel combustion, and mining and smelting of nonferrous metals in and beyond the TP. Air mass backward trajectories revealed that potential pollutants were transported not only from local sources but also from Xinjiang Province in northwestern China, as well as South Asia, Central Asia, the Middle East, and Europe. Plastics have been widely reported to be present in the environment yet there are still many questions regarding the extent of this and the impacts these may have on both the environment and human health. The purpose of this investigation is to determine levels of micro and mesoplastic (MP), in the 1-5000 μm range, in commercially important species of finfish and shellfish. Additionally, to determine and compare the relative MP levels in edible versus non-edible tissues, and consider the wider implications in terms of human health concerns with a preliminary risk identification approach. For several fish species, samples taken from typically non-edible (gills, digestive system) and edible (muscle) flesh, and were analysed separately. Scallops, where all tissues are edible, were analysed whole. Significant differences were observed in the number of particles isolated from the finfish gills and digestive tissues relative to the control samples, but not in the edible flesh. CH6953755 chemical structure For scallops, the abundance of particles in the Scottish samples did not vary significantly from the control, while the Patagonian scallops displayed significantly higher numbers of MPs. Characterisation of MPs by FTIR microscopy found that 16-60% (depending on species) were polyethylene terephthalate (PET) and polyethylene (PE) in origin. The risk identification results validate MPs as an emerging risk in the food chain and establish seafood as a vector for the exposure and uptake of MPs through the ingestion route for humans. Levels of MPs in seafood, and a direct link to the human food chain, suggests that their quantification be included as one food safety measure. Manure pH may vary depending on its inherent composition or additive contents. However, the effect of pH on the fate of antibiotics and antibiotic resistance determinants in manure remains unclear. This work demonstrated that pH adjustment promoted the removal of different sulfonamide antibiotics (SAs) within swine manure under incubation conditions, which increased from 26-60.8% to 75.0-86.0% by adjusting the initial pH from neutral (7.4) to acidic (5.4-4.8). Acidification was also demonstrated to inhibit the accumulation of antibiotic resistance genes in manure during incubation. Acidified manure contained both lower absolute and relative abundances of sul1 and sul2 than those at a neutral pH like 7.4. Further investigation indicated that acidification promoted the reduction of sul genes in manure by restricting sulfonamide-resistant bacteria (SRB) proliferation and inhibiting IntI1 accumulation. Furthermore, pH adjustment significantly influenced the composition of the manure bacterial community after incubation, which increased Firmicutes and decreased Proteobacteria.