The major (Al) and trace metal (Cu, Pb, Zn, Cr, Cd, and As) concentrations in 29 surface sediment samples from the intertidal Jiaozhou Bay (JZB) are evaluated to assess the contamination level. The ...results show that the overall sediment quality in the area has been obviously impacted by trace metal contamination. The geoaccumulation index and the enrichment factor values indicate that no Cr or Cu contamination has occurred on the whole, only a few stations have been polluted by As, and some areas have been polluted by Cd, Pb, and Zn. Principal component analysis suggests that the Cu, Pb, Zn, and Cd are derived from anthropogenic inputs and that Cr, As, Cu, and Zn are influenced by natural weathering processes. Cu and Zn may originate from both natural and anthropogenic sources. The contamination in the northeastern JZB is higher than that in other areas of the bay.
•The trace metal concentrations in the intertidal Jiaozhou Bay are analyzed.•The area's sediments are characterized by high levels of trace metals.•Possible trace metal sources are discussed.•The anthropogenic inputs of Cd and Pb are the most significant.
Fibroblast growth factor 21 (FGF21) is a metabolic hormone with pleiotropic effects on glucose and lipid metabolism and insulin sensitivity. It acts as a key downstream target of both peroxisome ...proliferator-activated receptor α and γ, the agonists of which have been used for lipid lowering and insulin sensitization, respectively. However, the role of FGF21 in the cardiovascular system remains elusive.
The roles of FGF21 in atherosclerosis were investigated by evaluating the impact of FGF21 deficiency and replenishment with recombinant FGF21 in apolipoprotein E(-/-) mice. FGF21 deficiency causes a marked exacerbation of atherosclerotic plaque formation and premature death in apolipoprotein E(-/-) mice, which is accompanied by hypoadiponectinemia and severe hypercholesterolemia. Replenishment of FGF21 protects against atherosclerosis in apolipoprotein E(-/-)mice via 2 independent mechanisms, inducing the adipocyte production of adiponectin, which in turn acts on the blood vessels to inhibit neointima formation and macrophage inflammation, and suppressing the hepatic expression of the transcription factor sterol regulatory element-binding protein-2, thereby leading to reduced cholesterol synthesis and attenuation of hypercholesterolemia. Chronic treatment with adiponectin partially reverses atherosclerosis without obvious effects on hypercholesterolemia in FGF21-deficient apolipoprotein E(-/-) mice. By contrast, the cholesterol-lowering effects of FGF21 are abrogated by hepatic expression of sterol regulatory element-binding protein-2.
FGF21 protects against atherosclerosis via fine tuning the multiorgan crosstalk among liver, adipose tissue, and blood vessels.
Developing a scalable approach to construct efficient and multifunctional electrodes for the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) is ...an urgent need for overall water splitting and zinc–air batteries. In this work, a freestanding 3D heterostructure film is synthesized from a Ni‐centered metal−organic framework (MOF)/graphene oxide. During the pyrolysis process, 1D carbon nanotubes formed from the MOF link with the 2D reduced graphene oxide sheets to stitch the 3D freestanding film. The results of the experiments and theoretical calculations show that the synergistic effect of the N‐doped carbon shell and Ni nanoparticles leads to an optimized film with excellent electrocatalytic activity. Low overpotentials of 95 and 260 mV are merely needed for HER and OER, respectively, to reach a current density of 10 mA cm−2. In addition, a high half‐wave potential of 0.875 V is obtained for the ORR, which is comparable to that of Pt/RuO2 and ranks among the top of non‐noble‐metal catalysts. The use of an “all‐in‐one” film as the electrode leads to excellent performance of the homemade water electrolyzer and zinc–air battery, indicating the potential of the film for practical applications.
A freestanding 3D heterostructure film stitched by a metal−organic framework (MOF)‐derived carbon nanotube (CNT) microsphere superstructure and reduced graphene oxide (rGO) sheets is synthesized. The high specific surface area, hierarchical pores, controlled dopants, and conductive CNT@rGO heterostructure render the freestanding film as having excellent multifunctional activity and superior stability toward the hydrogen evolution reaction, oxygen evolution reaction, and oxygen reduction reaction.
Unreasonable use of chemical fertilizer (CF) on agricultural soil leads to massive losses of soil organic carbon (SOC) and total nitrogen (TN) in tropical and subtropical areas, where soil conditions ...are unfavorable for aggregate formation. This study evaluated the effects of combined application of biogas slurry (BS) plus CF on soil aggregation and aggregate-associated C/N concentration and storage in an Ultisol. Six treatments included: no fertilizer (T1), CF only (T2), partial (15% (T3), 30% (T4) and 45% (T5)) substitution of TN with BS and BS only (T6). Soil mechanical-stable aggregates (MSAs) formation and stability as well as MSAs-associated C/N concentration and storage were observed in different aggregate sizes (>5, 5-2, 2-1, 1.0-0.5, 0.50-0.25 and <0.25 mm). The proportion of MSAs >5 mm significantly increased with BS substitution (T5), while the proportions of MSAs 1.0-0.5 mm, MSAs 0.50-0.25 mm and MSAs <0.25 mm significantly decreased. Both mean weight diameter and geometric mean diameter were highest in T5, which improved soil aggregation stability as well as resulted in significantly higher SOC and TN concentrations and storage in MSAs >0.5 mm that constituted 72-82% of MSAs. Stepwise regression analysis showed that MSAs >5 mm, SOC in MSAs >5 mm and TN in MSAs >5 mm were the dominant variables affecting aggregate stability. Meanwhile SOC in MSAs <0.25 mm and TN in MSAs 2-1 mm were independent variables affecting SOC and TN concentrations in bulk soils. Therefore, certain rate of combined application of BS plus CF is an effective, eco-friendly way to improve soil quality in an Ultisol.
Both nitrogen deposition (ND) and microplastics (MPs) pose global change challenges. The effects of MPs co-existing with ND on ecosystem functions are still largely unknown. Herein, we conducted a ...10-month soil incubation experiment to explore the effects of polyethylene (PE) and polylactic acid (PLA) MPs on soil multifunctionality under different ND scenarios. We found that the interactions between ND and MPs affected soil multifucntionality. FAPROTAX function prediction indicated that both ND and MPs affected C and N cycling. ND increased some C-cycling processes, such as cellulolysis, ligninolysis, and plastic degradation. MPs also showed stimulating effects on these processes, particularly in the soil with ND. ND significantly decreased the abundance of functional genes NifH, amoA, and NirK, leading to inhibited N-fixation, nitrification, and denitrification. The addition of MPs also modified N-cycling processes: 0.1% PE enriched the bacterial groups for nitrate reduction, nitrate respiration, nitrite respiration, and nitrate ammonification, and 1% PLA MPs enriched N-fixation bacteria at all ND levels. We found that ND caused lower soil pH but higher soil N, decreased bacterial diversity and richness, and changed the composition and activity of functional bacteria, which explains why ND changed soil functions and regulated the impact of MPs.
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•Combined effects of MPs and ND on soil multifunctionality were first explored.•Both MPs and ND changed soil bacterial communities and their functions.•Both MPs and ND modified soil multifunctionality, particularly C and N cycling.•The effects of MPs varied with the type and dose of MPs and the ND levels.•ND enriched the functional bacteria for plastic degradation.
Protein oxidation results in structural modification which affects its functionalities. In this study, 2,2′-azobis (2-amidinopropane) dihydrochloride (AAPH) was selected as a representative of lipid ...peroxidation products to investigate the effect of oxidative modification on structural and foaming properties of egg white protein. Incubation of egg white protein with AAPH resulted in structural changes, regarding by sulfhydryl-disulfide interchange reaction and increase in dityrosine formation. Moderate oxidation led to exposure of hydrophobic groups of egg white protein, whereas, excessive oxidation induced a decrease in surface hydrophobicity. Molecular weight distribution and scanning electron microscopy showed that egg white protein underwent an aggregation after excessive oxidation. Furthermore, after treating with AAPH at 0.2 mM, the foaming ability of egg white protein increased from 85.6% to 91.4%, and the foaming stability increased from 80.6% to 85.3%. The excessive oxidation treatment (5 and 25 mmol/L AAPH) resulted in an enhanced foaming ability, while reduced its foaming stability. This study suggested that oxidation treatment has a potential to be implemented to modify foaming properties of egg white protein.
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•Oxidation treatment induced sulfhydryl-disulfide interchange and dityrosine formation in egg white protein.•Oxidation treatment changed surface hydrophobicity and secondary structure of egg white protein.•Excessive oxidation increased foaming ability of egg white protein, while decreased its foam stability.
Bread wheat expanded its habitat from a core area of the Fertile Crescent to global environments within ~10,000 years. The genetic mechanisms of this remarkable evolutionary success are not well ...understood. By whole-genome sequencing of populations from 25 subspecies within the genera Triticum and Aegilops, we identified composite introgression from wild populations contributing to a substantial portion (4-32%) of the bread wheat genome, which increased the genetic diversity of bread wheat and allowed its divergent adaptation. Meanwhile, convergent adaptation to human selection showed 2- to 16-fold enrichment relative to random expectation-a certain set of genes were repeatedly selected in Triticum species despite their drastic differences in ploidy levels and growing zones, indicating the important role of evolutionary constraints in shaping the adaptive landscape of bread wheat. These results showed the genetic necessities of wheat as a global crop and provided new perspectives on transferring adaptive success across species for crop improvement.
Adiponectin plays a key role in the regulation of the whole-body energy homeostasis by modulating glucose and lipid metabolism. Although obesity-induced reduction of adiponectin expression is ...primarily ascribed to a transcriptional regulation failure, the underlying mechanisms are largely undefined. Here we show that DNA hypermethylation of a particular region of the adiponectin promoter suppresses adiponectin expression through epigenetic control and, in turn, exacerbates metabolic diseases in obesity. Obesity-induced, pro-inflammatory cytokines promote DNMT1 expression and its enzymatic activity. Activated DNMT1 selectively methylates and stimulates compact chromatin structure in the adiponectin promoter, impeding adiponectin expression. Suppressing DNMT1 activity with a DNMT inhibitor resulted in the amelioration of obesity-induced glucose intolerance and insulin resistance in an adiponectin-dependent manner. These findings suggest a critical role of adiponectin gene epigenetic control by DNMT1 in governing energy homeostasis, implying that modulating DNMT1 activity represents a new strategy for the treatment of obesity-related diseases.
The heavy metals in surface sediments of the continental shelf of the South Yellow Sea (SYS) and the East China Sea (ECS) collected in 2016 were analyzed to assess the heavy metal distributions, ...contamination status, and likely sources. The metal concentrations generally met the China Marine Sediment Quality criteria. However, the enrichment factor and geoaccumulation index values clearly showed elevated Cd and Pb concentrations in the region. Cd and Pb contamination occurred mostly to the southwest of the Changjiang River mouth and to the east of the Shandong Peninsula because of rapid economic and industrial development. The results are likely to be useful for authorities responsible for sustainable coastal zone management.
•Heavy metals in the sediment of the continental shelf of the SYS and ECS were analyzed.•The sediments are characterized by low levels of heavy metals.•The anthropogenic inputs of Cd and Pb are the most significant.•Heavy contamination occurred along the eastern coast of Shandong Peninsula and southwest of the Changjiang River mouth.
Background & Aims Acetaminophen (APAP) overdose causes hepatic necrosis and acute liver injury by inducing mitochondrial dysfunction and damage. Although the biochemical pathways that mediate ...APAP-induced hepatotoxicity have been well studied, the body’s defense mechanism to attenuate this disease remains elusive. This study investigated the roles of adiponectin, an adipocyte-secreted adipokine with pleiotropic protective effects against obesity-related metabolic dysfunction, in the pathogenesis of APAP-induced liver injury in mice. Methods Adiponectin knockout (ADN KO) and C57 wild type mice were treated with an overdose of APAP, followed by histological and biochemical evaluation of liver injury and activation of autophagy. The mechanism of adiponectin in APAP-induced hepatocytic toxicity was also explored in primary cultured hepatocytes. Results APAP overdose triggers a marked accumulation of adiponectin in injured liver tissues. ADN KO mice exhibit severely exacerbated mitochondrial dysfunction and damage, oxidative stress and necrosis and much higher mortality in response to APAP overdose, whereas these changes are reversed by a single injection of adiponectin. Mechanistically, adiponectin induces autophagosome formation by AMP-activated protein kinase (AMPK)-dependent activation of the Unc-51-like kinase 1, consequently leading to the removal of damaged mitochondria from hepatocytes. The protective effects of adiponectin against APAP-induced mitochondrial damage, oxidative stress and necrosis are abrogated by blockage of AMPK or pharmacological inhibition of autophagy. Conclusions Our findings suggest that the APAP-induced accumulation of adiponectin in liver tissues serves as an adaptive mechanism to ameliorate hepatotoxicity by promoting autophagy-mediated clearance of damaged mitochondria. Adiponectin agonists may represent a promising therapy for the drug-induced acute liver failure.
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