Goodfitch9930

This study evaluated the allelopathy, uptake and accumulation, and potential agricultural and food safety risks of nicotine in broad bean (Vicia faba L.) during seed germination and seedling growth. Nicotine stress has an allelopathic inhibitory effect on seeds and a hormesis effect on germinated seeds and seedlings, which has an enhancement effect (200 mg kg-1) on the seedlings. Exogenous nicotine can be absorbed by broad bean roots from nicotine-contaminated soil and accumulated in the main organs of the seedlings, especially the leaves, which exceeded the maximum residue level (0.03 mg kg-1 DW) at 50 mg kg-1. Moreover, nicotine resulted in a bitter taste in the edible broad bean leaves, disrupting the balance of basic nutritional properties, decreasing sucrose, and increasing bitter substances such as choline and procyanidin. These results demonstrated that residual nicotine in the soil not only poses potential risks to sustainable agricultural development but also a food safety risk for consumers. The present study provides insight into the potential risks of nicotine in agroecosystems.Yeasts are the most predominant petroleum hydrocarbon-degrading fungi isolated from petroleum-contaminated soil. However, information of the transmembrane transport of petroleum hydrocarbon into yeast cells is limited. The present study was designed to explore the transmembrane transport mechanisms of the typical petroleum hydrocarbon n-hexadecane in Candida tropicalis cells with petroleum hydrocarbon biodegradation potential. Yeast cells were treated with n-hexadecane in different scenarios, and the percentage of intracellular n-hexadecane and transport dynamics were investigated accordingly. The intracellular concentration of n-hexadecane increased within 15 min, and transportation was inhibited by NaN3, an ATPase inhibitor. The uptake kinetics of n-hexadecane were well fitted by the Michaelis-Menten model, and Kt values ranged from 152.49 to 194.93 mg/L. All these findings indicated that n-hexadecane might cross the yeast cells in an energy-dependent manner and exhibit an affinity with the cell transport system. Moreover, the differentially expressed membrane proteins induced by n-hexadecane were identified and quantified by tandem mass tag labeling coupled with liquid chromatography tandem mass spectrometry analysis. The proteome analysis results demonstrated that energy production and conversion accounted for a large proportion of the functional classifications of the differentially expressed proteins, providing further evidence that sufficient energy supply is essential for transmembrane transport. Protein functional analysis also suggested that differentially expressed proteins associated with transmembrane transport processes are clearly enriched in endocytosis and phagosome pathways (p less then 0.05), and the analysis supported the notion that the underlying transmembrane transport mechanism might be associated with endocytosis and phagosome pathways, revealing a new mechanism of n-hexadecane internalization by Candida tropicalis.A total of 90 wooden toys were collected, and six wood preservatives (chlorophenols and lindane) were analyzed by using gas chromatography-tandem mass spectrometry to assess the exposure risk of children to wood preservatives through oral contact with wooden toys. The detection rates of six preservatives ranged from 2.2% to 22.2%. The contents of the preservatives ranged from 0.6 µg/kg to 9.6 µg/kg. 2,4-Dichlorophenol (2,4-DCP) and 2,4,6-trichlorophenol (2,4,6-TCP) had higher detection rates and contents than other preservatives. Thus, their migration behaviors from toys to saliva were further investigated. In 11 positive samples, the max migration ratios of 2,4-DCP and 2,4,6-TCP ranged from 7.1% to 20.3% and from 11.1% to 24.8%, respectively. For children aged 3-36 months, the daily average 2,4-DCP exposure level associated with wooden toys ranged from 2.7 pg/(kg day) to 46.9 pg/(kg day), and the daily average 2,4,6-TCP exposure ranged from 3.6 pg/(kg day) to 69.4 pg/(kg day). The contribution to exposure provided by the saliva mobilization pathway was more than that provided by the ingestion of scraped-off toys, and the exposure level of 2,4,6-TCP was greater than that of 2,4-DCP. The max hazard quotient for 2,4-DCP was 1.9 × 10-4, and the max cancer risk for 2,4,6-TCP was 1.2 × 10-9. The above results indicated that although wood preservatives were distributed in wooden toys, exposure arising from directly mouthing these materials currently does not pose unacceptable risks to children.Cell division cycle 37 (Cdc37) is an important cytoplasmic phosphoprotein, which usually functions as a complex with heat shock protein 90 (Hsp90), to effectively reduce the damage caused by heavy metals, such as cadmium (Cd), in aquatic animals. The high toxicity of Cd in aquatic systems generally has a deleterious effect on healthy farming of shrimps. In the present study, a novel Cdc37 gene from Penaeus monodon was identified and designated as PmCdc37. Selleck RIN1 Following exposure to Cd stress, the expression levels of PmCdc37 were upregulated at the transcriptional level in both the hepatopancreas and hemolymph. RNA interference and recombinant protein injection experiments were carried out to determine the function of PmCdc37 in P. monodon following Cd exposure. To clarify the correlations between PmCdc37 and PmHsp90, the respective recombinant proteins were expressed in vitro, and the ATPase activity of PmHsp90, with or without PmCdc37, was assessed. Moreover, a pull-down assay was conducted to detect the correlation between PmCdc37 and PmHsp90. After analyzing the expression patterns of PmHsp90 following Cd challenge, whether PmHsp90 can promote the ability of PmCdc37 to resist Cd stress or not was investigated. The results showed that formation of a PmHsp90/PmCdc37 complex protected shrimp against Cd stress-induced damage. Moreover, we also confirmed that PmSOD is involved in Cd stress, and that the PmHsp90/PmCdc37 complex can regulate SOD enzymatic activity. PmSOD was involved in decreasing the MDA content in shrimp hemolymph caused by Cd stress. We concluded that during exposure to Cd, the PmHsp90/PmCdc37 complex increases SOD enzyme activity, and in turn decreases the MDA content, thereby protecting shrimp against the damage caused by Cd stress. The present studies contribute to understanding the molecular mechanism underlying resistance to Cd stress in shrimp.