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1.
Proc Natl Acad Sci U S A ; 120(21): e2300066120, 2023 May 23.
Article in English | MEDLINE | ID: mdl-37186821

ABSTRACT

It is now well known that solids under ultra-high-pressure shock compression will enter the warm dense matter (WDM) regime which connects condensed matter and hot plasma. How condensed matter turns into the WDM, however, remains largely unexplored due to the lack of data in the transition pressure range. In this letter, by employing the unique high-Z three-stage gas gun launcher technique developed recently, we compress gold into TPa shock pressure to fill the gap inaccessible by the two-stage gas gun and laser shock experiments. With the aid of high-precision Hugoniot data obtained experimentally, we observe a clear softening behavior beyond ~560 GPa. The state-of-the-art ab-initio molecular dynamics calculations reveal that the softening is caused by the ionization of 5d electrons in gold. This work quantifies the partial ionization effect of electrons under extreme conditions, which is critical to model the transition region between condensed matter and WDM.

2.
Nanotechnology ; 27(42): 425503, 2016 Oct 21.
Article in English | MEDLINE | ID: mdl-27640550

ABSTRACT

Hierarchical nanostructures with much increased surface-to-volume ratio have been of significant interest for prototypical gas sensors. Herein we report a novel resistive gas sensor based on TiO2/V2O5 branched nanoheterostructures fabricated by a facile one-step synthetic process, in which well-matched energy levels induced by the formation of effective heterojunctions between TiO2 and V2O5, a large Brunauer-Emmett-Teller surface area and complete electron depletion for the V2O5 nanobranches induced by the branched-nanofiber structures are all beneficial to the change of resistance upon ethanol exposure. As a result, the ethanol sensing performance of this device shows a lower operating temperature, faster response/recovery behavior, better selectivity and about seven times higher sensitivity compared with pure TiO2 nanofibers. This study not only confirms the gas sensing mechanism for performing enhancement of branched nanoheterostructures, but also proposes a rational approach to the design of nanostructure-based chemical sensors with desirable performance.

3.
Poult Sci ; 103(9): 104027, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39024690

ABSTRACT

Phytic acid (PA) is a natural antioxidant with various biological activities, providing protective effects in multiple animals. Ochratoxin A (OTA) is a mold toxin commonly found in feed, which induces multi-organ damage, with kidney being the target organ of its toxicity. This study investigates the protective effects of PA on OTA-induced renal damage and its potential mechanisms in chicks. The results demonstrates that PA treatment restores OTA-induced renal pathological injuries, reverses the diminished activities of antioxidant enzymes, reduces the accumulation of malondialdehyde, and normalizes the expression of pro-inflammatory cytokines, which confirms that PA can alleviate OTA-induced renal damage. Further investigations reveal that OTA-induced renal injury accompanied by an increase in tissue iron content and the transcription levels of ferroptosis-related genes (TFR, ACSL4, and HO-1), and a decrease in the levels of SLC7A11 and GPX4. PA treatment reverses all these effects, indicating that PA mitigates OTA-induced renal ferroptosis. Moreover, PA supplementation improves intestinal morphology and mucosal function, corrects OTA-induced changes in the intestinal microbiota. Besides, PA microbiota transplantation alleviates renal inflammation and oxidative stress caused by OTA. In conclusion, PA plays a protective role against renal damage through the regulation of ferroptosis and the intestinal microbiota, possibly providing novel insights into the control and prevention of OTA-related nephrotoxicity.


Subject(s)
Chickens , Ferroptosis , Gastrointestinal Microbiome , Ochratoxins , Phytic Acid , Poultry Diseases , Animals , Ochratoxins/toxicity , Gastrointestinal Microbiome/drug effects , Ferroptosis/drug effects , Poultry Diseases/chemically induced , Poultry Diseases/prevention & control , Poultry Diseases/microbiology , Poultry Diseases/drug therapy , Phytic Acid/administration & dosage , Phytic Acid/pharmacology , Kidney Diseases/veterinary , Kidney Diseases/chemically induced , Kidney Diseases/prevention & control , Animal Feed/analysis , Diet/veterinary , Male , Dietary Supplements/analysis
4.
J Agric Food Chem ; 72(33): 18682-18696, 2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39135376

ABSTRACT

Ochratoxin A (OTA) is a prevalent mycotoxin found in feed that causes significant kidney injury in animals. Further investigation was needed to devise strategies for treating OTA-induced kidney damage through the gut-kidney axis. Evidence indicates the crucial role of intestinal microbiota in kidney damage development. Inulin, a dietary fiber, protects kidneys by modulating intestinal microbiota and promoting short-chain fatty acid (SCFA) production. However, its precise mechanism in OTA-induced kidney damage remained unclear. In this study, chickens were orally administered OTA and inulin for 2 weeks to investigate inulin's effects on OTA-induced kidney damage and underlying mechanisms. The alteration of intestinal microbiota, SCFAs contents, and SCFA receptors was further analyzed. Results demonstrated that inulin supplementation influenced intestinal microbiota, increased SCFAs production, and mitigated OTA-induced kidney damage in chickens. The importance of microbiota in mediating inulin's renal protection was further confirmed by antibiotic and fecal microbiota transplantation experiments. Additionally, inulin exhibited antioxidant and anti-inflammatory properties, alleviating NLRP3 inflammasome activation and pyroptosis. In summary, inulin protected chickens from OTA-induced kidney damage, which might provide a potential strategy to mitigate the harmful effects of mycotoxins through prebiotics and safeguard renal health.


Subject(s)
Chickens , Gastrointestinal Microbiome , Inulin , Kidney , Ochratoxins , Ochratoxins/toxicity , Animals , Inulin/administration & dosage , Gastrointestinal Microbiome/drug effects , Kidney/drug effects , Kidney/metabolism , Bacteria/classification , Bacteria/isolation & purification , Bacteria/genetics , Bacteria/drug effects , Bacteria/metabolism , Dietary Supplements/analysis , Fatty Acids, Volatile/metabolism , Poultry Diseases/microbiology , Poultry Diseases/drug therapy , Poultry Diseases/prevention & control , Animal Feed/analysis , Male , Kidney Diseases/metabolism , Kidney Diseases/prevention & control , Kidney Diseases/etiology
5.
Poult Sci ; 102(10): 102946, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37542939

ABSTRACT

Zearalenone (ZEA) is produced mainly by fungi belonging to genus Fusarium in foods and feeds. Heterophil extracellular traps (HETs) are a novel defense mechanism of chicken innate immunity involving activated heterophils. However, the conditions and requirements for ZEA-triggered HET release remain unknown. In this study, immunostaining analysis demonstrated that ZEA-triggered extracellular fibers were composed of histone and elastase assembled on DNA skeleton, showing that ZEA can induce the formation of HETs. Further experiments indicated that ZEA-induced HET release was concentration-dependent (ranging from 20 to 80 µM ZEA) and time-dependent (ranging from 30 to 180 min). Moreover, in 80 µM ZEA-exposed chicken heterophils, reactive oxygen species (ROS) level, catalase (CAT), superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, and glutathione (GSH) content were increased. Simultaneously, ZEA at 80 µM activated ERK and p38 MAPK signaling pathways by increasing the phosphorylation level of ERK and p38 proteins. Pharmacological inhibition assays revealed that blocking nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, ERK, and p38 mitogen-activated protein kinase (MAPK) reduced ZEA-induced ROS levels but had no impact on HET formation. Furthermore, immunostaining analysis indicated that the heterophil underwent the formation of autophagosome based on being stained with LC3B. The pharmacological inhibition assays demonstrated that rapamycin-, wortmannin-, and 3-methyladenine (3-MA)-treatments modulated ZEA-triggered HET formation, indicating that heterophil autophagy played a key role in ZEA-induced HET formation. Further studies on energy metabolism showed that inhibition of lactate/glucose transport, hexokinase-2 (HK-2), fructose-2,6-biphosphatase 3 (PFKFB3) in glycolysis abated ZEA-induced HETs, implying that glycolysis was one of the factors influencing the ZEA-induced HET formation. Besides, inhibition of the peptidylarginine deiminase (PAD) enzyme and P2X1 significantly reduced the ZEA-induced HET formation. In conclusion, we demonstrated that ZEA-triggered HET formation, which was associated with glycolysis, autophagy, PAD enzyme, and P2X1 receptor activation, providing valuable insight into the negative effect of ZEA on chicken innate immunity.


Subject(s)
Extracellular Traps , Zearalenone , Animals , Extracellular Traps/metabolism , Reactive Oxygen Species/metabolism , Chickens/metabolism , Zearalenone/toxicity , Protein-Arginine Deiminases/metabolism , Protein-Arginine Deiminases/pharmacology , Autophagy , Glycolysis
6.
J Oleo Sci ; 72(11): 1027-1035, 2023.
Article in English | MEDLINE | ID: mdl-37914264

ABSTRACT

Acute liver injury (ALI), posing a serious threaten to our life, has emerged as a public health issue around the world. ß-carotene has plenty of pharmacologic effects, such as anti-inflammatory, antioxidant, and antitumor activities. In this study, we focused on studying the protective role and potential molecular mechanisms of ß-carotene against D-galactosamine (D-GalN) and lipopolysaccharide (LPS) induced ALI. Our results indicated that ß-carotene pretreatment effectively hindered abnormal changes induced by LPS/D-GalN in liver histopathology. Meanwhile, serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were downgraded with ß-carotene pretreatment. ß-carotene pretreatment also decreased malondialdehyde content and myeloperoxidase activity, increased glutathione peroxidase and superoxide dismutase levels, and reduced the levels of tumor necrosis factor-a (TNF-α) and interleukin 6 (IL-6) in liver tissues. Further investigations found that ß-carotene mediated multiple signaling pathways in LPS/D-GalN-induced ALI, inhibiting NF-κB and MAPK signaling and upregulating the expression of Nrf2 and HO-1 proteins. All findings indicate that ß-carotene appears to protect mice against LPS/D-GalN induced ALI by reducing oxidative stress and inflammation, possibly via regulating NF-κB, MAPK, and Nrf2 signaling.


Subject(s)
Chemical and Drug Induced Liver Injury , NF-kappa B , Animals , Mice , Antioxidants/pharmacology , Antioxidants/metabolism , beta Carotene/pharmacology , Chemical and Drug Induced Liver Injury/prevention & control , Galactosamine/toxicity , Galactosamine/metabolism , Lipopolysaccharides , Liver/metabolism , NF-E2-Related Factor 2/metabolism , NF-kappa B/metabolism , Tumor Necrosis Factor-alpha/metabolism
7.
Angew Chem Int Ed Engl ; 51(36): 9123-7, 2012 Sep 03.
Article in English | MEDLINE | ID: mdl-22887953

ABSTRACT

The dielectric constant and electrical conductivity of a composite of two insulators, poly(1,1-difluoroethylene) (yellow) and K(2)CO(3) (white), increased dramatically near the percolation threshold f(c) (f=concentration of K(2)CO(3)). This intriguing phenomenon can be interpreted in terms of interface percolation caused by the formation of chemically activated interfaces.

8.
Sci Rep ; 6: 33092, 2016 09 12.
Article in English | MEDLINE | ID: mdl-27615429

ABSTRACT

Much greater surface-to-volume ratio of hierarchical nanostructures renders them attract considerable interest as prototypical gas sensors. In this work, a novel resistive gas sensor based on TiO2/Ag0.35V2O5 branched nanoheterostructures is fabricated by a facile one-step synthetic process and the ethanol sensing performance of this device is characterized systematically, which shows faster response/recovery behavior, better selectivity, and higher sensitivity of about 9 times as compared to the pure TiO2 nanofibers. The enhanced sensitivity of the TiO2/Ag0.35V2O5 branched nanoheterostructures should be attributed to the extraordinary branched hierarchical structures and TiO2/Ag0.35V2O5 heterojunctions, which can eventually result in an obvious change of resistance upon ethanol exposure. This study not only indicates the gas sensing mechanism for performance enhancement of branched nanoheterostructures, but also proposes a rational approach to design nanostructure based chemical sensors with desirable performance.

9.
Nanoscale ; 6(12): 6790-7, 2014 Jun 21.
Article in English | MEDLINE | ID: mdl-24827710

ABSTRACT

Titanium dioxide has attracted considerable interest as a prototypical semiconductor photocatalyst. However, because of the relative large bandgap energy, further application of TiO2 photocatalyst is limited by its inefficient solar energy conversion. Various attempts have been made to broaden the light absorption window of the TiO2, such as growth of TiO2-based heterostructures. Herein, a novel three-component system, Ag2O/TiO2/V2O5 one-dimensional nanoheterostructures with enhanced solar light absorption, is prepared by depositing Ag2O nanoparticles onto the surface of TiO2/V2O5 nanofibers through a two-step synthetic process. This three-component system exhibits excellent solar-driven photocatalytic activity, far exceeding those of the single- and two-component systems, as a result of extended solar light absorption and efficient electron-hole separation. Furthermore, the photocatalytic performance of Ag2O/TiO2/V2O5 one-dimensional nanoheterostructures is very stable for recycling use.

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