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Mesotrione, topramezone, tembotrione, and sulcotrione are four types of 4-hydroxyphenylpyruvate dioxidase (HPPD) inhibitor herbicides that are extensively employed in agricultural practices, but their usage also leads to environmental pollution and poses risks to human health. A probe (E)−1-((2-(pyridin-2-yl) hydrazineylidene) methyl) naphthalen-2-ol (CHMN) based on chelation enhancement (CHEF) effect synthesized. CHMN was first chelated with Zn2+ to form a probe system with green, which can be further used to detect mesotrione, topramezone, tembotrione and sulcotrione in complicated environment. CHMN-Zn2+ detection of four pesticides was accurate, with an excellent linear relationship between 0 and 100 μM. The detection limits were LOD mesotrione = 7.79 μM, LOD topramezone = 1.91 μM, LOD tembotrione = 1.38 μM and LOD sulcotrione = 2.43 μM. The detection time is 1 min, and it is successfully applied in real water sample and bioimaging. This work can provide a novel method for studying the migration and behavior of environmental pollutants. [Display omitted] • A novel Zn2+-coordination fluorescent probe for sensing HPPD inhibitors was synthesized. • CHMN has low cytotoxicity, high sensitivity and and good selectivity. • CHMN can detect HPPD inhibitors in environmental water samples. • CHMN can visualize the migration and behavior of HPPD inhibitors in vivo in real time. [ABSTRACT FROM AUTHOR]

Understanding the physiological effects of herbicides on crops is crucial for crop production and environmental management. The effects of 4-hydroxyphenylpyruvate dioxygenase inhibitor (HPPDi) herbicides at different concentrations on chlorophyll content in maize leaves, fresh weight of roots, stems and leaves, and fluorescence substances and functional groups in root exudates (REs) were studied by UV-Vis absorption spectroscopy, fluorescence spectroscopy, Fourier transform infrared spectroscopy (FTIR) and two-dimensional correlation analysis (2D-COS). The results showed that 5 mg/L and 10 mg/L HPPDi herbicides inhibited the synthesis of chlorophyll in maize leaves. The weight of roots, stems and leaves of maize after application was lighter than that of the control group. HPPDi herbicides affected the early growth of maize seedlings, and the effect was most obvious at high concentration. Synchronous fluorescence spectrum and three-dimensional (3D) fluorescence spectrum revealed that the fluorescence intensity of protein, fulvic acid and humic acid in maize REs changed prominently. With the increase of HPPDi herbicides concentration, the fluorescence intensity decreased gradually. Through FTIR and 2D-COS, functional groups such as C-H, C O, Cl, NO 3 -, C-O and O-H were found to participate in the interaction between HPPDi herbicides and maize REs as binding sites. C-O, C-Cl and C-C have the strongest binding ability, while C C and C O of aromatic rings, quinones or ketones first take part in the binding between HPPDi herbicides and maize REs. The results can provide a theoretical basis for evaluating the safety of HPPDi herbicides on maize and a method for discovering the effects of pesticides on environmental media and plant physiological effects. [Display omitted] • 5 mg/L and 10 mg/L HPPDi inhibited the synthesis of chlorophyll in maize leaves. • HPPDi affected the fresh weight of maize roots, stems and leaves. • HPPDi reduced the fluorescence intensity of protein, FA and HA in REs. • REs bind to HPPDi through C-H, C O, Cl, NO 3 -, C-O and O-H. [ABSTRACT FROM AUTHOR]

Eutrophication of lacustrine environments with frequent cyanobacterial blooms has become a serious problem. Overpopulation and runoff into groundwater and lakes from fertilizers with too much nitrogen and phosphorous have caused most of the problems. Here, we first devised a land use and cover classification system based on the local characteristics of the first-level protected area of Lake Chaohu (FPALC). Lake Chaohu is the fifth largest freshwater lake in China. The land use and cover change (LUCC) products were produced using sub-meter resolution satellite data from 2019 to 2021 in the FPALC. This study presents an evaluation of the effectiveness of the established protected areas. The results show the most impactful type was the reduction in cropland with an area that declined from 7446.4 hm2 to 6433.3 hm2 from 2019 to 2021. Most of the reduced cropland was converted into wetlands, with 460.2 hm2 and 152.0 hm2 of cropland restored to wetlands from 2019 to 2020 and 2020–2021, respectively. The area of cyanobacterial blooms in Lake Chaohu showed a downward trend, and the lacustrine environment was greatly improved after the establishment of the FPALC. These quantified data can inform decision-making related to Lake Chaohu conservation and provide a reference for managing the aquatic environment in other watersheds. [Display omitted] • Watershed LUCC was mapped using very high-resolution satellite data (∼0.5 m). • A new LUCC classification system is designed for protected area. • LUCC trends and underlying drivers in the protected area were quantified. • The effect of protected area on lacustrine environments was evaluated. • The establishment of FPALC improved the lacustrine environment. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs) have been developed with numerous beneficial applications. However, rodent models demonstrate that exposure to MWCNTs via respiratory pathways results in pulmonary fibrosis. Therefore, they could elicit a potential risk of pulmonary fibrosis in humans due to occupational or consumer exposure. Sirtuin 6 (SIRT6), a nicotinamide adenine dinucleotide (NAD)-dependent deacetylase, has been proved to prevent fibrosis in the liver, renal and myocardial tissues. In this present study, we aimed to explore the role of SIRT6 in MWCNTs-induced epithelial-mesenchymal transition (EMT), one of the major contributor of lung fibrogenesis in human bronchial epithelial BEAS-2B cells. We found that the protein level of SIRT6 was elevated after exposure to MWCNTs in BEAS-2B cells. Overexpression of SIRT6 significantly inhibited MWCNTs-induced EMT and EMT-like cell behaviors in BEAS-2B cells. Moreover, wild-type SIRT6 was found to decrease MWCNTs-induced phosphorylation of Smad2, but not mutant SIRT6 (H133Y) without histone deacetylase activity. In conclusion, our study demonstrated that SIRT6 inhibited MWCNTs-induced EMT in BEAS-2B cells through TGF-β1/Smad2 signaling pathway, which depended on its deacetylase activity, and provided evidences that targeting SIRT6 could be a potential novel therapeutic strategy for MWCNTs-induced pulmonary fibrosis. • Sirtuin 6 (SIRT6) was elevated after exposure to MWCNTs in BEAS-2B cells. • SIRT6 overexpression inhibited MWCNTs-induced epithelial-mesenchymal transition (EMT). • SIRT6 inhibited EMT via TGF-β1/Smad2 pathway, depending on its deacetylase activity. • SIRT6 is a promising target to protect against MWCNTs-induced pulmonary fibrosis. [ABSTRACT FROM AUTHOR]

The key odorants of Jiugui -series Baijiu (Y and R) were explored systematically for the first time by a sensory-directed flavor analysis approach. A total of 144 aroma-active compounds were identified by pH regulated liquid-liquid extraction (LLE) and headspace solid phase microextaction (HS-SPME) combined with gas chromatography-olfactometry-mass spectrometry (GC-O-MS), and 92 of these were first reported. The aroma extract dilution analysis (AEDA) was used for screening the potential important aroma compounds. The overall aroma profiles of Y and R were successfully simulated (similarity = 95.47%, and 90.21%, respectively) by mixing the odorants (OAV ≥ 1) with their natural concentrations in 52% ethanol/water solutions. The omission tests revealed that ethyl acetate, ethyl lactate, ethyl butyrate, ethyl pentanoate, ethyl hexanoate, ethyl octanoate, ethyl dodecanoate, dimethyl trisulfide, acetic acid, propionic acid, butanoic acid, isovaleric acid, hexanoic acid, octanoic acid, and p -cresol were identified as the key aroma compounds. In particular, benzenemethanethiol played an important role in the typical aroma of Y and R, which had a burnt or baked-like odor and was a new finding. • The key odorants of Fuyu-flavor-type Baijiu (FFTB) were explored for the first time. • 92 compounds were newly identified as aroma-active odorants in FFTB. • Benzenemethanethiol played an important role in the typical aroma of FFTB. • 10 important compounds' odor thresholds in ethanol/water solution were evaluated. [ABSTRACT FROM AUTHOR]

Infertility affects about 10–15% couples over the world, among which a large number of cases the underlying causes are still unclear. Recent studies suggest that environmental factors may play an important role in these idiopathic infertilities. Arsenic is a heavy metal found in drinking water over the world. Its effect on the development of female reproductive system at the environmental-relevant levels is still largely unknown. To test the hypothesis that arsenic exposure during juvenile and puberty may affect sex maturation and female reproductive system development, SD rats of 3 weeks of age were exposed to arsenic with environmental-relevant levels (0, 0.02, 0.2, or 2 mg/L, n = 16/group) through drinking water for about 44 days until the rats reached adulthood (65 days of age). Arsenic exposure significantly reduced the weights of both ovary and uterus without affecting the body weight. Also, arsenic exposure disturbed estrus cycles and reduced the numbers of primordial follicles and corpora lutea while increased atretic follicles. In addition, arsenic reduced serum levels of estradiol, progesterone and testosterone but increased LH and FSH levels in dose-dependent manners. QPCR and Western blot experiments indicated arsenic selectively down-regulated ovarian steroidogenic-related proteins FSHR, STAR, CYP17A1, HSD3B1 and CYP19A1 and signaling molecules PKA-ERK-JNK-cJUN, without affecting AKT and CREB. As about reproductive capacity, arsenic-exposed dams had smaller pups, reduced litter size and lower number of male pups without a change in female pups. In conclusion, juvenile and pubertal arsenic exposures at environmental-relevant levels significantly reduced reproductive functions and capacity by adult. Since the lowest effective dose is very close to the government safety standards, the relevancy of arsenic over exposure to reproductive defects in human deserves further study. [Display omitted] • Pubertal arsenic exposure significantly disturbed the estrous cycles by adult. • Arsenic affected the numbers of primordial and atretic follicles and corpora lutea. • Arsenic reduced serum levels of E2, P4 and T but increased the levels of LH and FSH. • Arsenic down-regulated steroidogenic proteins STAR, HSD3B1, CYP17A1 and CYP19A1. • Arsenic reduced pup weights, litter size and changed the sex-ratio of the offspring. [ABSTRACT FROM AUTHOR]

4-Hydroxyphenylpyruvate dioxygenase (HPPD) inhibitor is one of the important herbicides to solve the problem of weed control. With the widespread and continued use of HPPD inhibitor (HPPDi) herbicides, it may inevitably put pressure on the environment. Humic acid (HA) can effectively interact with pesticides through sorption or covalent bond formation and promote the degradation of pesticides, which can reduce the risk of pesticides in the environment. In the present study, the interactions of four HPPDi herbicides (sulcotrione, tembotrione, topramezone and mesotrione) with HA were reported and comparative assessment of the binding using multispectral technology, density functional theory (DFT) calculation and two-dimensional correlation spectroscopy (2D-COS). Time-resolved measurements and the Stern-Volmer constant at different temperature verified that HPPDi can bind with HA through the static quenching mechanism. From the thermodynamic parameters, the interaction force between HA and sulcotrione, tembotrione, topramezone and mesotrione was provided by electrostatic force. DFT, binding constant and three-dimensional (3D) fluorescence peak variation all indicated that the order of the binding ability of the four HPPDi and HA was mesotrione > tembotrione > sulcotrione > topramezone. According to dynamic light scattering (DLS), pH 7 is most conducive to the formation of HA-HPPDi complexes. Fourier transform infrared spectroscopy (FTIR) and 2D-COS showed that HA combined with HPPDi through aromatic C-H, C O and C-X, and the first binding group to HA was almost all C O. Sulcotrione, tembotrione, topramezone and mesotrione quench the endogenous fluorescence of HA by a static quenching mechanism and bind to HA through electrostatic interaction to form a complex. These results provide important insights into the combination of environmental pollutants with HA. [Display omitted] • HPPDi quenched the endogenous fluorescence of HA. • HA-HPPDi complex was formed through electrostatic interaction. • The binding capacity of mesotrione with HA was the strongest. • The main functional group of HA binding to HPPDi is C O. • pH 7 is prone to the formation of HA-HPPDi complex. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) have been demonstrated to play critical roles in the pathogenesis of human cancers and carcinogenesis of several environmental pollutants. Nevertheless, the function of circRNAs in cadmium carcinogenesis is unclear. circ-SHPRH is down-regulated in many cancers including non-small cell lung cancer. In our present study, during cadmium-induced transformation of human bronchial epithelial BEAS-2B cells, epithelial-mesenchymal transition (EMT) was induced. Meanwhile, at the middle and late stages of cell transformation, cadmium down-regulated the expression of circ-SHPRH, as well as QKI, a tumor suppressor protein known to prevent the proliferation and EMT during progression of human cancers, compared with passage-matched control BEAS-2B cells. Overexpression of circ-SHPRH in cadmium-transformed BEAS-2B cells promoted the expression of QKI and significantly inhibited proliferation, EMT, invasion, migration and anchorage-independent growth in soft agar of the cells. Mechanistic studies showed that circ-SHPRH functioned as a sponge of miR-224–5p to regulate QKI expression. Interestingly, QKI and circ-SHPRH could form a positive-feedback loop that perpetuated circ-SHPRH/miR-224–5p/QKI axis. Collectively, our results demonstrated that circ-SHPRH inhibited cadmium-induced transformation of BEAS-2B cells through sponging miR-224–5p to regulate QKI expression under cadmium treatment. Our study uncovered a novel molecular mechanism involved in circRNAs in the development of lung cancer due to cadmium exposure. [Display omitted] • Circ-SHPRH was decreased during cadmium-induced transformation of BEAS-2B cells. • Circ-SHPRH acted as an miR-224–5p sponge and downregulated miR-224–5p target QKI. • Downregulated QKI promoted cell transformation induced by cadmium. • Circ-SHPRH and QKI could provoke a positive-feedback loop in cadmium-treated cells. • Circ-SHPRH and QKI are promising targets to protect against cadmium-induced lung cancer. [ABSTRACT FROM AUTHOR]

There has been a great concern about the neurotoxicity of fluoride since it can pass through the blood-brain barrier and accumulate in the brain. It has been suggested that apoptosis plays a vital role in neurotoxicity of fluoride. However, whether p53-mediated apoptotic pathway is involved is still unclear. Our results showed that apoptosis was induced after treatment with 40 and 60 mg/L of NaF for 24 h in human neuroblastoma SH-SY5Y cells. Exposure to 60 mg/L of NaF for 24 h significantly upregulated the levels of p53 and apoptosis-related proteins including PUMA, cytochrome c (cyto c ), cleaved caspase-3 and cleaved PARP, whereas downregulated Bcl-2 in SH-SY5Y cells. Meanwhile, fluoride increased p53 nuclear translocation, cyto c release from mitochondria to cytoplasm and mitochondrial translocation of Bax in SH-SY5Y cells. Fluoride-induced increases of apoptotic rates and apoptosis-related protein levels were significantly attenuated by inhibiting p53 transcriptional activity with pifithrin-α. In addition, fluoride inhibited the deacetylase activity of SIRT1 and increased p53 (acetyl K382) level in SH-SY5Y cells. Apoptosis and upregulation of cleaved caspase-3, cleaved PARP and p53 (acetyl K382) induced by fluoride could be ameliorated by SIRT1 overexpression or its activator resveratrol in SH-SY5Y cells. Taken together, our study demonstrates that fluoride induces apoptosis by inhibiting the deacetylase activity of SIRT1 to activate mitochondrial p53 pathway in SH-SY5Y cells, which depends on p53 transcriptional activity. Thus, SIRT1 may be a promising target to protect against neurotoxicity induced by fluoride. [ABSTRACT FROM AUTHOR]

Due to its important geographic location and unique environment, the Gansu and Qinghai region in China has been witnessing the emergence and development of Chinese civilization. This previously neglected region has recently been attracting people's attention. Existing studies have been mainly aiming to relate the spatiotemporal distributions of settlements to environmental changes. However, they generally fail to consider the evolution of social organizations and its role in impacting the spatiotemporal variations of prehistoric settlements. In this paper, we analyzed the spatiotemporal distribution and rank-size of prehistoric settlements in the Gansu-Qinghai region based on GIS analytical methods and reconstructed the process of cultural inheritance and social evolution. The examined chronological periods were demonstrated to be concomitant with different settlement development patterns, and most settlements in an older period were abandoned in the subsequently younger period, indicating poor inheritance. The occurrence of a three-tier regional settlement system during the late Yangshao–Majiayao period indicates fundamental changes in social organization, which is possibly related to the rise of a chiefdom-level society. Such a regional social stratification was intensified during the Qijia period, when a four-tier settlement system emerged. However, the complexity of the settlement system got weakened during the Bronze Age, as is indicated by the lowered hierarchy of the settlement system. The drying and cooling climatic event rendered nomadism the prevalent subsistence among the humans in the Gansu and Qinghai region who used to survive by participating in agricultural activities. • Use Gis to analyse the settlement morophology. • Use the rank-size to analyse the settlement system. • Development of trajectories settlement system. [ABSTRACT FROM AUTHOR]

The purpose of this study is to examine the association between hourly air pollution on hourly physical activity (PA) and sedentary behavior (SB) among college students in Beijing, China. The secondary aim was to examine such associations varied at specific time. A total of 340 participants were recruited from the Tsinghua University, in Beijing, China. Accelerometers provided PA measures, including moderate-to-vigorous physical activity (MVPA), walking steps, energy expenditure and sedentary time for 7 consecutive days. Corresponding air pollution data by the Beijing Municipal Ecological Environment Bureau in the closed site (Wan Liu site) in Tsinghua University were collected including average hourly air quality index (AQI) and PM 2.5 (μg/m³). Associations were estimated using linear individual fixed-effect regressions. We also conducted an air pollution risk perception survey among 2307 freshmen (76.6% males) who were enrolled in Tsinghua in 2016, and the survey was done in May 22–26, 2017. A one level increase in hourly air quality index (AQI) was associated with a reduction in 1-h PA by 0.083 (95% confidence interval [CI] = -0.137, −0.029) minutes of MVPA, 8.8 (95% CI = −15.0, −2.6) walking steps, 0.65 (95% CI = -1.03, −0.27) kcals of energy expenditure. A 10 μg/m³ increase in air pollution concentration in hourly PM 2.5 was associated with a reduction in 1-h PA by 0.021 (95% confidence interval [CI] = -0.033, −0.010) minutes of MVPA, 2.2 (95% CI = −3.5, −0.9) walking steps, 0.170 (95% CI = -0.250, −0.089) kcals of energy expenditure an increase in 1-h sedentary behavior 0.045 (0.005, 0.0845). At specific time, stronger negative associations of AQI and PM 2.5 air pollution with PA at 8 a.m., 4 p.m., 5 p.m. and 7 p.m. Similarly, stronger positive associations of 1 h AQI and PM 2.5 air pollution with SB at 8 a.m., 9 a.m., 11 a.m., and 7 p.m. A total of 94.9% participants (n = 2235) responded "yes" to air pollution change activities in the survey, which may partially explain PA change. Air pollution may discourage physical activity and increases sedentary behavior among freshman students living in Beijing, China. This is preliminary study. The impact of air pollution on physical activity and sedentary behavior at a specific time may be different. There are large variations in walking steps in specific time. Trend for walking steps in specific time in one day among the freshman. Image 1 • Air pollution may discourage physical activity behavior. • Air pollution may increase sedentary behavior. • The impact of air pollution on health behavior may be different at a specific time. [ABSTRACT FROM AUTHOR]