Effect of acute PM2.5 exposure on PTGS2 and RNA m6A modification.

Particulate matter 2.5 (PM2.5) is a prevalent risk factor in many diseases, but its molecular mechanism remains ambiguous and may be diverse. RNA m6A is an important epigenetic modification that regulates gene expression at the post-transcriptional level. Some previous animal exposure studies found that PM2.5 exposure up-regulated m6A RNA methylation in the lung, but there is no research on m6A RNA methylation in humans from PM2.5 exposure now. Here, in the present experiment, we performed a panel study of 65 students at the Chinese research academy of environmental sciences (CRAES) with 3 rounds of follow-up visits from August 2021 to January 2022. We examined m6A RNA modification profiles of peripheral blood mononuclear cells (PBMCs) from subjects after low and high concentrations of ambient PM2.5 exposure. We applied a linear mixed-effect (LME) model to investigate the association between PM2.5 exposure and global m6A RNA methylation and PTGS2 level in peripheral blood. We found that increased levels of global m6A RNA methylation and PTGS2 level were associated with higher PM2.5 exposure. Among the methylated mRNAs, PTGS2 was hyper-methylated after high concentrations of PM2.5 exposure, which coincided with the increased expression of PTGS2 mRNA. In the present study, we determined that PM2.5 exposure promoted RNA m6A modification, and PTGS2 in peripheral blood could serve as a novel regulatory factor of inflammation induced by PM2.5 exposure. Furthermore, RNA m6A modification may contribute to the altered expression of PTGS2 induced by PM2.5 exposure. Our finding provided a new perspective for the prevention and treatment of PM2.5 exposure-induced adverse health effects.

Exposure to ambient air pollution from the preconceptional period and risk of gestational hypertension.

Although accumulative studies have revealed the associations between air pollutants and elevated risk of gestational hypertension (GH), evidence from developing countries with relatively higher levels of air pollutants remains limited. In this retrospective study, a total of 45,439 birth records were collected in Beijing, China from 2013 to 2018. For PM2.5, SO2, NO2, and O3, exposure windows from the 3rd month of preconception to the 6th month of conception and the averages of 3 months of preconception, trimester 1 and trimester 2 periods were all calculated for assessment of GH risks. The correlations between air pollutants and the risk of GH were analyzed by logistic regression model. Our results showed that exposure to PM2.5 and SO2 in the preconceptional and early pregnancy periods was related to the elevated risk of GH. Furthermore, 3 months preconceptional exposure to PM2.5 (PCPM2.5: OR = 1.134 (1.114, 1.155)) and SO2 (PCSO2: OR = 1.158 (1.135, 1.181)) showed a higher risk of GH than the results of the trimester 1 (T1PM2.5: OR = 1.131 (1.104, 1.159); T1SO2: OR = 1.164 (1.141, 1.187)) and the trimester 2 (T2PM2.5: OR = 1.154 (1.126, 1.182); T2SO2: OR = 1.121 (1.098, 1.144)). The study also found significant and higher OR values for PCPM2.5, and PCSO2 from 2013 to 2016 when air pollution was serious in Beijing compared with 2017 to 2018 when the air pollution was obviously improved. Subgroup analysis also found that during 3 months of preconception women with higher age and who exposure to higher temperatures showed higher GH risk from PM2.5 and SO2 than that of the younger group and who exposure to lower temperature, respectively. Collectively, our findings suggest that air pollution exposure was adversely associated with GH in pregnant women and the preconceptional period is a critical air pollution exposure window for GH. Improving air quality can benefit public health, especially for sensitive populations like pregnant women.

In-situ conversion of geopolymer into novel floral magnetic sodalite microspheres for efficient removal of Cd(II) from water.

In the present work, a novel, floral-like, magnetic sodalite microsphere (SODM) was synthesized in situ by using fly ash (FA) and metakaolin (MK) as raw materials and was used to remove Cd(II) from water. Its magnetism can solve the problems of adsorbent recovery and possible secondary pollution. During the static adsorption, SODM shows a maximum adsorption capacity of 245.17 mg/g. The adsorption of Cd(II) on the SODM surface is spontaneous, exothermic, and physicochemical adsorption, which was evaluated by thermodynamics, kinetics, and isotherm studies. During dynamic adsorption, SODM shows a maximum adsorption capacity of 342.74 mg/g in the simulated solution prepared by the deionized water, compared to 215.88 mg/g in the simulated solution prepared using Xiangsi Lake water from Guangxi Minzu University. At 0.5 g SODM dosage in the dynamic adsorption, the adsorption capacity could rise to 632.81 mg/g. These results demonstrated the excellent Cd (II) adsorption performance of the SODM. The adsorption of cadmium on the SODM surface includes the synergistic effects of electrostatic attraction, ion exchange, and surface coordination reaction. Besides, the SODM shows good regeneration performance in both the deionized water and Xiangsi Lake water. The present study explores SODM as an adsorbent for the Cd (II) removal from wastewater and unbolts the industrial applicability of the SODM in the field of wastewater purification.

Influence of different concentrations of ozone on the alteration of mitochondrial DNA copy numbers in human peripheral blood.

By now, O3 pollution has become a main environmental problem. O3 is a prevalent risk factor for many diseases, but the regulatory factors linking O3 and diseases remain ambiguous. Mitochondrial DNA (mtDNA) is the genetic material in mitochondria, which plays a key role in the production of respiratory ATP. Due to a lack of histone protection, mtDNA is easily damaged by ROS, and O3 is an important source to stimulate the production of endogenous ROS in vivo. Therefore, we logically speculate that O3 exposure can alter mtDNA copy number by the induction of ROS. In the present study, we performed a panel study of 65 MSc students at the Chinese research academy of environmental sciences (CRAES) with 3 rounds of follow-up visits from August 2021 to January 2022. We examined the mtDNA copy numbers in the peripheral blood of subjects using quantitative polymerase chain reaction. Linear mixed-effect (LME) model and stratified analysis were used to investigate the association between O3 exposure and mtDNA copy numbers. We found a dynamic process of the association between the concentration of O3 exposure and the mtDNA copy number in the peripheral blood. The lower concentration of O3 exposure did not affect the mtDNA copy number. As the concentration of O3 exposure increased, the mtDNA copy number also increased. While, when O3 exposure reached a certain concentration, a decrease in mtDNA copy number was found. This correlation between the concentration of O3 and the mtDNA copy number could be ascribed to the severity of cellular damage induced by O3 exposure. Our results provide a new perspective for the discovery of a biomarker of O3 exposure and health response, as well as for the prevention and treatment of adverse health effects caused by different concentrations of O3.

Identification of mixing water source and response mechanism of radium and radon under mining in limestone of coal seam floor.

With the gradual increase of the coal mining depth, the mixing of multiple water sources intensifies and the activity of radium and radon in groundwater increases. Identifying the source of mine water inrush by using radium and radon isotopes is a new choice. In this paper, the mathematical statistics method, radioactive isotope decay theory, the mass conservation principle, and the numerical simulation method are used to analyze the influence of total dissolved solids (TDS), pH, and the hydrochemical ion content in groundwater on the isotope activity of radium, radon, uranium, thorium, and lead. The activity of thorium and lead is lower than the detection limit of the instrument, and the influence of coal mining activities on it is small. The simulation of the radium-radon mass balance in groundwater shows that the greater the adsorption coefficient (k) of solid particles in groundwater is, the more obvious the adsorption effect and the greater the influence on the radium-radon activity balance are. The radium-radon dating method is used to calculate the groundwater age. Results show that the groundwater age in the closed pit coal mining area is generally older than that in the mining coal mining area. Combined with the 222Rn, 226Ra, and 234U radioactive isotopes and temperature, a mixing water source identification model of limestone in the coal seam floor is constructed. The model shows that the radium activity and temperature of the groundwater are inversely proportional to the mixing ratio of the Permian sandstone water. From the closed pit coal mining area to the mining coal mining area, the radium radon activity of the groundwater increases gradually, the groundwater age decreases significantly, the water cycle is accelerated, the mixing ratio of the Permian sandstone water decreases gradually, the mixing ratio of the Ordovician limestone water increases gradually, and the risk of coal mine water inrush increases. The research results prove the feasibility of the new method for accurately discriminating the mixing water sources in coal mine areas, which is of great significance to the improvement of the theory of coal mine water disaster prevention and control.

Acute effects of exposure to fine particulate matter and ozone on lung function, inflammation and oxidative stress in healthy adults.

Both fine particulate matter (PM2.5) and ozone (O3) may have adverse effects on human health. However, previous studies on the effects of air pollutants mainly have focused on susceptible population, and evidence on healthy young adults is limited. We aimed to examine the associations of the two main air pollutants (PM2.5 and O3) with lung function, inflammation and oxidative stress in healthy young adults. We recruited 30 healthy young adults for a longitudinal panel study in Beijing and implemented health examination seven times, including lung function (FEV1 and PEF) and biomarkers of inflammation and oxidative stress (i.e. C-reactive protein, CRP; interleukin-6, IL-6; malondialdehyde, MDA) from December 2019 to May 2021. Hourly ambient air pollutants data were obtained from the closest air quality monitoring station. Linear mixed-effect model was applied to explore the associations between air pollutants and lung function, inflammation and oxidative stress. We observed higher PM2.5 exposure was associated with decrement in lung function and increment in CRP and MDA. Each 10 µg/m3 increase in PM2.5 (lag 2 day) is associated with a 17.06 ml (95% CI: -31.53, -2.58) decrease in FEV1, 46.34 ml/s (95% CI: -76.41, -16.27) decrease in PEF and increments of 2.86% (95% CI: 1.47%, 4.27%) in CRP, 1.63% (95% CI: 0.14%, 3.14%) in MDA respectively. However, there is no significant association between ozone exposure and health indicators. The study suggested that short-term exposure to PM2.5 may decrease lung function and induce inflammation and oxidative stress in healthy adults, but there is no association between O3 and each outcome.

Enhance the removal and immobilization of Cd(II) by the synthesis in situ of dithiocarbamate-geopolymer microsphere composite.

In this study, slag-based geopolymer microspheres (SGS) were combined with dithiocarbamate (DTC) to synthesize the composite adsorbent of SGS and DTC in situ (SGS-DTC). Synthesis was carried out with optimal dosages of 10 mL of EDA, 1.0 g of SGS, and 20 mL of CS2. The differences in material properties, performance, and mechanisms in the adsorption and immobilization of toxic Cd(II) in water between SGS and SGS-DTC were investigated. SGS-DTC showed better adsorption performance than SGS, irrespective of adsorbent dosage, pH, original content, and contact duration. Although after the Cd(II) adsorption, the immobilization performance at a different pH was better in the SGS-DTC than in the SGS, the immobilization performance was unaffected by changes in the other factors. For static adsorption, the adsorption rate of SGS-DTC (1.5 h) was faster than that of SGS (6 h); the Cd(II) adsorption capacity of SGS-DTC (211.2 mg/g) was almost twice that of SGS (116.7 mg/g), and correspondingly, the removal rate of SGS-DTC (99.75%) was nearly twice that of SGS (53.2%). For dynamic adsorption, the adsorption capacity of SGS-DTC was 389.78 mg/g, which is considerably higher than that of SGS (293.38 mg/g) in the Cd(II) solution prepared with deionized water. Furthermore, the adsorption capacity of the SGS-DTC was 299.26 mg/g, which is significantly higher than that of SGS (150.03 mg/g) in the Cd(II) solution prepared by the river water from Yongjiang, Nanning, Guangxi, China. One reason is that DTC was able to activate Si-O-Si without adsorption performance within SGS, thereby improving its adsorption and purification properties significantly. The other reason is that, after anchoring DTC on SGS, the specific surface area varied from 34.05-146.47 m2/g, the morphology was smooth-leaf-like, the pore volume was 0.13-0.20 cm3/g, and the pore size in SGS, was 14.75-5.60 nm. The high potential of SGS-DTC in removing and immobilizing heavy metal materials in wastewater is demonstrated in the results.

KOH-Activated Geopolymer Microspheres Recycle Co(II) with Higher Adsorption Capacity than NaOH-Activated Ones.

A new type of absorbent with high efficiency was synthesized by KOH-activated slag-based geopolymer microspheres (K-SGM), which exhibited higher adsorption capacities for recycling Co(II) (Q e,K-SGM = 192.31 mg/g, Q e,Na-SGM = 91.21 mg/g) than NaOH-activated ones (Na-SGM). During the Co(II) adsorption process, these two kinds of geopolymeric adsorbents could be combined with heavy metal ions to optimize each other and form heavy metal-grown aid adsorbents. The morphology of Na-SGM and K-SGM was different which varied from coarse pores to nanonetwork or nanosheets after Co(II) adsorption, and the Brunauer-Emmett-Teller (BET) surface areas of Na-SGM (10.46 m2/g) and K-SGM (22.96 m2/g) increased to 117.38 and 228.73 m2/g after Co(II) adsorption, respectively. The BET surface area of K-SGM is twice that of Na-SGM whether before or after Co(II) ion adsorption. The hydrated ionic radius of K and Na, the alkalinity degree of K+ and Na+, the electronegativity of Na-SGM and K-SGM surface, the BET surface area and Fourier transform infrared changes of CO3 2- and OH before and after Co(II) adsorption, and X-ray photoelectron spectroscopy analysis like the relative content of geopolymer gel and bridging oxygen bonds in the Na-SGM and K-SGM are the fundamental reasons for the obvious differences in Co(II) adsorption between Na-SGM and K-SGM.

Prepared self-growing supported nickel catalyst by recovering Ni (â ¡) from metal wastewater using geopolymer microspheres.

Here, new and effective microsphere adsorbents were synthesized by NaOH activating slag based geopolymer (Na-SGS). These microsphere adsorbents upset the adsorption equilibrium with the maximum Ni2+ adsorption capacity of 414.38 mg/g which is much larger than that of other geopolymer materials. After Ni2+ adsorption from simulated nickel electroplating wastewater, more active positions for the adsorption Ni2+ ions on Na-SGS were provided as shifts from the average pore diameter of 22.00-7.44 nm, the pore volume of 0.06 to 0.25 cm3/g, the Brunauer-Emmett-Teller (BET) surface area of 10.46-125.35 m2/g and the apparent change of new morphology. Moreover, the adsorbed Ni2+ species were distributed uniformly on Na-SGS. Thermodynamic performance reflected an exothermic, spontaneous and molecular disorder adsorption process, which can be easily controlled by the pH, dosage, initial concentration, contact time and temperature. Through the controllable adsorption, Na-SGS after Ni2+ adsorption (Na-SGS-Ni) was recycled and then reduced to be directly supported nickel catalysts (red-Na-SGS-Ni), which showed superior catalytic activity for CO2 methanation. Although the highest percent of CO2 conversation (XCO2 =99.54%) and methane selectivity (SCH4 =99.5%) are both at 300 °C, red-Na-SGS-Ni performed good XCO2 (99.48%) and SCH4 (98.2%) at low temperatures (100 °C).

A cytogenetic analysis of male meiosis in Asparagus officinalis.

Asparagus (Asparagus officinalis) has several traits that make it a useful model for cytogenetic studies, however, few studies of the meiosis process have been made in asparagus. Here, we present in detail an atlas of male meiosis in asparagus, from preleptotene to telophase II. The meiosis process in asparagus is largely similar to those of the well-characterized model plants Arabidopsis thaliana, Zea mays, and Oryza sativa. However, most asparagus prophase I meiotic chromosomes show a strongly aggregated morphology, and this phenotype persists through the pachytene stage, highlighting a property in the control of chromosome migration and distribution in asparagus. Further, we observed no obvious banding of autofluorescent dots between divided nuclei of asparagus meiocytes, as one would expect in Arabidopsis. This description of wild-type asparagus meiosis will serve as a reference for the analyses of meiotic mutants, as well as for comparative studies among difference species. Abbreviations: DAPI: 4',6-diamidino-2-phenylindole; FISH: fluorescence in situ hybridization; PBS: phosphate-buffered saline; PMC: pollen mother cell; SEM: Scanning Electron Microscope.