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Pharmacological inhibition of PAI-1 alleviates cardiopulmonary pathologies induced by exposure to air pollutants PM2.5
2021
Ghosh, Asish K. | Soberanes, Saul | Lux, Elizabeth | Shang, Meng | Aillon, Raul Piseaux | Eren, Mesut | Budinger, G.R Scott | Miyata, Toshio | Vaughan, Douglas E.
Numerous studies have established that acute or chronic exposure to environmental pollutants like particulate matter (PM) leads to the development of accelerated aging related pathologies including pulmonary and cardiovascular diseases, and thus air pollution is one of the major global threats to human health. Air pollutant particulate matter 2.5 (PM₂.₅)-induced cellular dysfunction impairs tissue homeostasis and causes vascular and cardiopulmonary damage. To test a hypothesis that elevated plasminogen activator inhibitor-1 (PAI-1) levels play a pivotal role in air pollutant-induced cardiopulmonary pathologies, we examined the efficacy of a drug-like novel inhibitor of PAI-1, TM5614, in treating PM₂.₅-induced vascular and cardiopulmonary pathologies. Results from biochemical, histological, and immunohistochemical studies revealed that PM₂.₅ increases the circulating levels of PAI-1 and thrombin and that TM5614 treatment completely abrogates these effects in plasma. PM₂.₅ significantly augments the levels of pro-inflammatory cytokine interleukin-6 (IL-6) in bronchoalveolar lavage fluid (BALF), and this also can be reversed by TM5614, indicating its efficacy in amelioration of PM₂.₅-induced increases in inflammatory and pro-thrombotic factors. TM5614 reduces PM₂.₅-induced increased levels of inflammatory markers cluster of differentiation 107 b (Mac3) and phospho-signal transducer and activator of transcription-3 (pSTAT3), adhesion molecule vascular cell adhesion molecule 1 (VCAM1), and apoptotic marker cleaved caspase 3. Longer exposure to PM₂.₅ induces pulmonary and cardiac thrombosis, but TM5614 significantly ameliorates PM₂.₅-induced vascular thrombosis. TM5614 also reduces PM₂.₅-induced increased blood pressure and heart weight. In vitro cell culture studies revealed that PM₂.₅ induces the levels of PAI-1, type I collagen, fibronectin (Millipore), and sterol regulatory element binding protein-1 and 2 (SREBP-1 and SREBP-2), transcription factors that mediate profibrogenic signaling, in cardiac fibroblasts. TM5614 abrogated that stimulation, indicating that it may block PM₂.₅-induced PAI-1 and profibrogenic signaling through suppression of SREBP-1 and 2. Furthermore, TM5614 blocked PM₂.₅-mediated suppression of nuclear factor erythroid related factor 2 (Nrf2), a major antioxidant regulator, in cardiac fibroblasts. Pharmacological inhibition of PAI-1 with TM5614 is a promising therapeutic approach to control air pollutant PM₂.₅-induced cardiopulmonary and vascular pathologies.
Mostrar más [+] Menos [-]Foliar architecture and physio-biochemical plasticity determines survival of Typha domingensis pers. Ecotypes in nickel and salt affected soil
2021
Akhter, Noreen | Aqeel, Muhammad | Hameed, Mansoor | Sakit Alhaithloul, Haifa Abdulaziz | Alghanem, Suliman Mohammed | Shahnaz, Muhammad Muslim | Hashem, Mohamed | Alamri, Saad | Khalid, Noreen | Al-zoubi, Omar Mahmoud | Iqbal, Muhammad Faisal | Masood, Tayyaba | Noman, Ali
Six ecotypes of Typha domingensis Pers. Jahlar (E₁), Sheikhupura (E₂), Sahianwala (E₃), Gatwala (E₄), Treemu (E₅) and Knotti (E₆) from different ecological regions were collected to evaluate the leaf anatomical and biochemical attributes under different levels of salinity and nickel stress viz; L₀ (control), L₁ (100 mM + 50 mg kg⁻¹), L₂ (200 mM + 100 mg kg⁻¹) and L₃ (300 mM + 150 mg kg⁻¹). Presence of salt and Ni in rooting medium consistently affected growth, anatomical and physio-biochemical attributes in all Typha ecotypes. Discrete anatomical modifications among ecotypes such as reduced leaf thickness, increased parenchyma area, metaxylem cell area, aerenchyma formation and improved metaxylem vessels were recorded with increasing dose of salt and Ni. The minimum anatomical damages were recorded in E₁ and E₆ ecotypes. In all ecotypes, progressive perturbations in ionic homeostasis (Na⁺, K⁺, Cl⁻, N) due to salt and metal toxicity were evident along with reduction in photosynthetic pigments. Maximum enhancement in Catalase (CAT), Superoxide dismutase (SOD), Peroxidase (POD) and modulated Malondialdehyde (MDA) activity was recorded in E₁ and E₆ as compared to other ecotypes. Accumulation of large amounts of metabolites such as total soluble sugars, total free amino acids content in Jahlar, Knotti, Treemu and Sahianawala ecotypes under different levels of salt and Ni prevented cellular damages in T. domingensis Pers. The correlation analysis exhibited a close relationship among different levels of salinity and Ni with various plant attributes. PCA-Biplot verified our correlational analysis among various attributes of Typha ecotypes. An obvious separation of Typha characters in response to different salinity and Ni levels was exhibited by PC1. We recommend that genetic potential of T. domingensis Pers. To grow under salt and Ni stresses must be investigated and used for phytoremediation and reclamation of contaminated soil.
Mostrar más [+] Menos [-]Biological selenite removal and recovery of selenium nanoparticles by haloalkaliphilic bacteria isolated from the Nakdong River
2021
Won, Sangmin | Ha, Myung-Gyu | Nguyen, Dinh Duc | Kang, Ho Young
Microbial selenite reduction has increasingly attracted attention from the scientific community because it allows the separation of toxic Se from waste sources with the concurrent recovery of Se nanoparticles, a multifunctional material in nanotechnology industries. In this study, four selenite-reducing bacteria, isolated from a river water sample, were found to reduce selenite by > 85% within 3 d of incubation, at ambient temperature. Among them, strain NDSe-7, belonging to genus Lysinibacillus, can reduce selenite and produce Se nanospheres in alkaline conditions, up to pH 10.0, and in salinity of up to 7.0%. This strain can reduce 80 mg/L of selenite to elemental Se within 24 h at pH 6.0–8.0, at a temperature of 30–40 °C, and salinity of 0.1–3.5%. Strain NDSe-7 exhibited potential for use in Se removal and recovery from industrial saline wastewater with high alkalinity. This study indicates that extremophilic microorganisms for environmental remediation can be found in a conventional environment.
Mostrar más [+] Menos [-]Polyethylene glycol acute and sub-lethal toxicity in neotropical Physalaemus cuvieri tadpoles (Anura, Leptodactylidae)
2021
Nascimento, Ítalo Freitas | Guimarães, Abraão Tiago Batista | Ribeiro, Fabianne | Rodrigues, Aline Sueli de Lima | Estrela, Fernanda Neves | Luz, Thiarlen Marinho da | Malafaia, Guilherme
Although many polymers are known by their toxicity, we know nothing about the impact of polyethylene glycol (PEG) on anurofauna. Its presence in different products and disposal in aquatic environments turn assessments about its impact on amphibians an urgent matter. Accordingly, we tested the hypothesis that short-time exposure (72 h) of tadpoles belonging to the species Physalaemus cuvieri (Anura, Leptodactylidae) to PEG induces oxidative stress and neurotoxicity on them. We observed that polymer uptake in P. cuvieri occurred after exposure to 5 and 10 mg/L of PEG without inducing changes in their nitrite levels neither at the levels of substances reactive to thiobarbituric acid. However, hydrogen peroxide and reactive oxygen species production was higher in animals exposed to PEG, whose catalase and superoxide dismutase levels were not enough to counterbalance the production of these reactive species. Therefore, this finding suggests physiological changes altering REDOX homeostasis into oxidative stress. In addition, the increased activity of acetylcholinesterase and butyrylcholinesterase, and reduction in superficial neuromasts, confirmed PEG’s neurotoxic potential. To the best of our knowledge, this is the first report on PEG’s biological impact on a particular amphibian species. The study has broadened the understanding about ecotoxicological risks associated with water pollution by these polymers, as well as motivated further investigations on its impacts on amphibians’ health and on the dynamics of their natural populations.
Mostrar más [+] Menos [-]Source contribution analysis of nutrient pollution in a P-rich watershed: Implications for integrated water quality management
2021
Han, Jianxu | Xin, Zhuohang | Han, Feng | Xu, Bo | Wang, Longfan | Zhang, Chi | Zheng, Yi
It is still a great challenge to address nutrient pollution issues caused by various point sources and non-point sources on the watershed scale. Source contribution analysis based on watershed modeling can help watershed managers identify major pollution sources, propose effective management plans and make smart decisions. This study demonstrated a technical procedure for addressing watershed-scale water pollution problems in an agriculture-dominated watershed, using the Dengsha River Watershed (DRW) in Dalian, China as an example. The SWAT model was improved by considering the constraints of soil nutrient concentration, i.e., nitrogen (N) and phosphorus (P), when modeling the nutrient uptake by a typical crop, corn. Then the modified SWAT model was used to quantify the contributions of all known pollution sources to the N and P pollution in the DRW. The results showed that crop production and trans-administrative wastewater discharge were the two dominant sources of nutrient pollution. This study further examined the responses of nutrient loss and crop yield to different fertilizer application schemes. The results showed that N fertilizer was the limiting factor for crop yield and that excessive levels of P were stored in the agricultural soils of the DRW. An N fertilizer application rate of approximately 40% of the current rate was suggested to balance water quality and environmental protection with crop production. The long-term impact of legacy P was investigated with a 100-year future simulation that showed the crop growth could maintain for 12 years even after P fertilization ceased. Our study highlights the need to consider source attribution, fertilizer application and legacy P impacts in agriculture-dominated watersheds. The analysis framework used in this study can provide a scientifically sound procedure for formulating adaptive and sustainable nutrient management strategies in other study areas.
Mostrar más [+] Menos [-]Nitrous oxide emission and sweet potato yield in upland soil: Effects of different type and application rate of composted animal manures
2021
Ruangcharus, Chuanpit | Kim, Sung Un | Yoo, Ga-young | Choi, Eun-Jung | Kumar, Sandeep | Kang, Namgoo | Hong, Chang Oh
The aims of this study were to determine type and application rate of composted animal manure to optimize sweet potato yield relative to N₂O emissions from upland soils. To this end, the study was conducted on upland soils amended with different types and rates of composted animal manure and located at two geographically different regions of South Korea. Field trials were established at Miryang and Yesan in South Korea during the sweet potato (Ipomoea batatas) growing season over 2 years: 2017 (Year 1) and 2018 (Year 2). Three composted animal manures (chicken, cow, and pig) were applied at the rates of 0, 10, and 20 Mg ha⁻¹ to upland soils in both locations. In both Years and locations, manure type did not affected significantly cumulative N₂O emissions from soil during the sweet potato growing season or the belowground biomass of sweet potato. However, application rate of animal manures affected significantly the cumulative N₂O emission, nitrogen (N) in soil, and belowground biomass of sweet potato. An increase in cumulative N₂O emission with application rates of animal manures was related to total N and inorganic N concentration in soil. The belowground biomass yield of sweet potato but also the cumulative N₂O emission increased with increasing application rate of composted animal manures up to 7.6 and 16.0 Mg ha⁻¹ in Miryang and Yesan, respectively. To reduce N₂O emission from arable soil while increasing crop yield, composted animal manures should be applied at less than application rate that produce the maximum belowground biomass of sweet potato.
Mostrar más [+] Menos [-]Estimations of benchmark dose for urinary metabolites of coke oven emissions among workers
2021
Zou, Kaili | Wang, Sihua | Wang, Pengpeng | Duan, Xiaoran | Yang, Yongli | Yazdi, Mahdieh Danesh | Stowell, Jennifer | Wang, Yanbin | Yao, Wu | Wang, Wei
Coke oven emissions (COEs), usually composed of polycyclic aromatic hydrocarbons (PAHs) and so on, may alter the relative telomere length of exposed workers and have been linked with adverse health events. However, the relevant biological exposure limits of COEs exposure has not been evaluated from telomere damage. The purpose of this study is to estimate benchmark dose (BMD) of urinary PAHs metabolites from COEs exposure based on telomere damage with RTL as a biomarker. A total of 544 exposed workers and 238 controls were recruited for participation. High-performance liquid chromatography and qPCR were used to detect concentrations of urinary mono-hydroxylated PAHs and relative telomere length in peripheral blood leukocytes for all subjects. The benchmark dose approach was used to estimate benchmark dose (BMD) and its lower 95% confidence limit (BMDL) of urinary OH-PAHs of COEs exposure based on telomere damage. Our results showed that telomere length in the exposure group (0.75 (0.51, 1.08)) was shorter than that in the control group (1.05 (0.76,1.44))(P < 0.05), and a dose-response relationship was shown between telomere damage and both 1-hydroxypyrene and 3-hydroxyphenanthrene in urine. The BMDL of urinary 1-hydroxypyrene from the optimal model for telomere damage was 1.96, 0.40, and 1.01 (μmol/mol creatinine) for the total, males, and females group, respectively. For 3-hydroxyphenanthrene, the BMDL was 0.94, 0.33, and 0.49 (μmol/mol creatinine) for the total, males, and females. These results contribute to our understanding of telomere damage induced by COEs exposure and provide a reference for setting potential biological exposure limits.
Mostrar más [+] Menos [-]Cumulative health risks for bisphenols using the maximum cumulative ratio among Chinese pregnant women
2021
Li, Jiufeng | Zhang, Wenxin | Zhou, Yanqiu | Shi, Jingchun | Xia, Wei | Xu, Shunqing | Cai, Zongwei
Bisphenol A and its alternatives are frequently detected in environmental and human samples, but studies associated with the pattern of combined health hazards from the exposure to the bisphenol mixtures are lacking, particularly for pregnant women. Here, we recruited 941 pregnant women with a full set of urine samples in the three trimesters collected under a cohort study project in Wuhan, China, between 2014 and 2015. We measured the concentrations of 8 bisphenols in 2823 urine samples, and calculated the average concentrations of bisphenols, which were detected in over 50% of samples, once during each trimester of pregnancy. We calculated the maximum cumulative ratio (MCR) on basis of estimated daily intake (EDI), hazard quotient (HQ), hazard index (HI) of three major bisphenols, including bisphenol A (BPA), bisphenol F (BPF), and bisphenol S (BPS), to find which one or mixtures drive risks. Participants were categorized into four groups according to their maximum HQ, HI and MCR values. We found negative relationships between log(MCR-1) and log(HI) with the slope (−0.6431). Percentage of HQ of BPA in HI ranged from 37.1% (<25th percentiles of HI) to 75.5% (>95th percentiles of HI) indicating the upward trend of dominance by BPA at increasing HI ranges. The cumulative health risks of bisphenol exposures largely originated from the health hazards of BPA and BPS, particularly BPA. The intervention for regulation on the production and application of BPA and its alternatives are urgent, and China should consider national regulation on these chemicals based on its risk to human health.
Mostrar más [+] Menos [-]A spatio-temporal noise map completion method based on crowd-sensing
2021
Huang, Min | Chen, Lina | Zhang, Yilin
The construction of noise maps is of great significance for the development of urban sustainability and the protection of residents’ physical and mental health. The traditional noise map construction method is difficult to be widely used because of its low update frequency and high drawing cost. Based on the crowd-sensing technology and Latent Factor Model (LFM), this paper proposes a new noise map completion method called Spatial-Temporally Related LFM (STR-LFM) for solving the problem of data sparseness. First, the geographic information features including Point of Interest (POI), road network and building outline are fully excavated, and then combine the correlation of the samples in the time dimension to construct the similarity matrixes. After that, use the k-nearest neighbor algorithm to find out the similar samples of missing positions, and finally regard their weighted fusion as the predicted values. Experimental results show that the recovery error is lower than other commonly used methods, and the proposed method has better stability when faced with data sparseness problems at different levels.
Mostrar más [+] Menos [-]Natural and anthropogenic impacts on the DOC characteristics in the Yellow River continuum
2021
Wen, Zhidan | Song, Kaishan | Shang, Yingxin | Lyu, Lili | Tao, Hui | Liu, Ge
The Yellow River is the second largest river in China. Carbon transport by the Yellow River has significant influence on riverine carbon cycles in Asia. During the wet season, the riverine carbon was mainly found in dissolved form, i.e., dissolved organic carbon (DOC), along the entire course of the river. The distinct spatial variations of DOC concentration were observed at different reaches of the mainstream (p < 0.01), while the highest mean DOC concentration was generally observed at midstream (4.13 ± 0.91 mg/L). Carbon stable isotope analysis δ¹³C and C: N ratio of DOC, evidenced the sources of DOC in headwater and upstream were primarily the terrestrial plants (94% and 61%), but it was changed to soil organic matter (SOM) in mid- and downstream (36% and 37%), and the contribution of sewage to DOC were also increased to 17% and 18%. In the whole mainstream of the Yellow River, water temperature (WT) had a significant impact on DOC concentration, and it could explain 67% of the DOC variance. However, in a large catchment, the driving mechanisms on the DOC variations in headwaters will not necessarily be those controlling DOC trends in downstream. The study firstly quantified, in headwater and upstream, the natural factors explained as much as 65% and 73% of the DOC variations, respectively. In mid- and downstream areas, DOC was significantly influenced by the amount of wastewater discharged by the industry and the use of chemical fertilizers (p < 0.05). These findings may facilitate a better assessment of global riverine carbon cycling and may help to reveal the importance of the balance between development and environmental sustainability with the changing DOC transport features in the Yellow River due to human disturbances.
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