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1.
J Hazard Mater ; 422: 126899, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34418838

RESUMO

Copper (Cu), a hazardous heavy metal, can lead to toxic effects on host physiology. Recently, specific mitochondria-localized miRNAs (mitomiRs) were shown to modulate mitochondrial function, but the underlying mechanisms remain undefined. Here, we identified mitomiR-1285 as an important molecule regulating mitochondrial dysfunction and mitophagy in jejunal epithelial cells under Cu exposure. Mitochondrial dysfunction and mitophagy were the important mechanisms of Cu-induced pathological damage in jejunal epithelial cells, which were accompanied by significant increase of mitomiR-1285 in vivo and in vitro. Knockdown of mitomiR-1285 significantly attenuated Cu-induced mitochondrial respiratory dysfunction, ATP deficiency, mitochondrial membrane potential reduction, mitochondrial reactive oxygen species accumulation, and mitophagy. Subsequently, bioinformatics analysis and luciferase reporter assay demonstrated that IDH2 was a direct target of mitomiR-1285. RNA interference of IDH2 dramatically reversed the effect that mitomiR-1285 knockdown relieved mitochondrial dysfunction and mitophagy induced by Cu, and the opposite effect was shown by overexpression of IDH2. Therefore, our results suggested that mitomiR-1285 aggravated Cu-induced mitochondrial dysfunction and mitophagy via suppressing IDH2 expression. These findings identified the important mechanistic connection between mitomiRs and mitochondrial metabolism under Cu exposure, providing a new insight into Cu toxicology.


Assuntos
MicroRNAs , Mitofagia , Animais , Cobre/toxicidade , Células Epiteliais , Mitocôndrias , Mitofagia/genética , Suínos
2.
Sci Total Environ ; : 152188, 2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34875328

RESUMO

As the primary source of electricity for various devices, batteries are important contributors to the overall electronic waste generated; and are widely considered a source of highly ecotoxic pollutants. Material leakage in battery manufacturing has not been completely solved, and the elucidation of the toxic mechanisms of battery wastewater exposure is needed. We demonstrated that battery waste exposure disrupted the intestinal flora and aggravated hepatotoxicity via the gut-liver axis. Under battery waste exposure, colon epithelium suffered physiological damage, and gene and protein expression levels related to gut barrier function (ZO-1, claudin-1, and Occludin) were significantly downregulated. Meanwhile, battery waste reduced the richness and diversity of the flora, causing metabolites produced by intestinal microbes to enter the gut-liver axis. Gut microbial dysbiosis impaired mitochondrial respiratory function in liver tissue cells, and mitophagy, apoptosis, and the disorder of glycolipids and amino acid metabolism were induced in hosts exposed to battery toxins. Altogether, these results provided novel insights into the underlying mechanisms of battery wastewater-related hepatotoxicity induced by gut microbiota via the gut-liver axis, which has public health implications where humans and animals are exposed to industrial toxins generated by uncontained battery disposal.

3.
Food Funct ; 12(20): 9642-9657, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34664585

RESUMO

Copper (Cu) is an essential trace mineral, but its excessive intake can lead to potentially toxic effects on host physiology. The mammalian intestine harbors various microorganisms that are associated with intestinal barrier function and inflammation. In this study, the influences of Cu on barrier function, microbiota, and its metabolites were examined in the jejunum and colon of pigs. Here, we identified that the physical and chemical barrier functions were impaired both in the jejunum and colon, as evidenced by the decreased expression of tight junction proteins (ZO-1, Occludin, Claudin-1, and JAM-1) and mucous secretion-related genes, positive rate of Muc2, and secretion of SIgA and SIgG. Additionally, inflammatory cytokines were overexpressed in the jejunum and colon. Furthermore, Cu might increase the abundances of Mycoplasma, Actinobacillus and unidentified_Enterobacteriaceae in the jejunum, which significantly affected pentose and glucoronate interconversions, histidine metabolism, folate biosynthesis, porphyrin metabolism, and purine metabolism. Meanwhile, the abundances of Lactobacillus and Methanobrevibacter were remarkably decreased and Streptococcus, unidentified_Enterobacteriaceae, and unidentified_Muribaculaceae were significantly increased in the colon, with an evident impact on glycerophospholipid metabolism, retinol metabolism, and steroid hormone biosynthesis. These findings revealed that excess Cu had significant effects on the microbiota and metabolites in the jejunum and colon, which were involved in intestinal barrier dysfunction and inflammation.

4.
Polymers (Basel) ; 13(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34372089

RESUMO

Conjugated polymers with narrower bandgaps usually induce higher carrier mobility, which is vital for the improved thermoelectric performance of polymeric materials. Herein, two indacenodithiophene (IDT) based donor-acceptor (D-A) conjugated polymers (PIDT-BBT and PIDTT-BBT) were designed and synthesized, both of which exhibited low-bandgaps. PIDTT-BBT showed a more planar backbone and carrier mobility that was two orders of magnitude higher (2.74 × 10-2 cm2V-1s-1) than that of PIDT-BBT (4.52 × 10-4 cm2V-1s-1). Both exhibited excellent thermoelectric performance after doping with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane, where PIDTT-BBT exhibited a larger conductivity (0.181 S cm-1) and a higher power factor (1.861 µW m-1 K-2) due to its higher carrier mobility. The maximum power factor of PIDTT-BBT reached 4.04 µW m-1 K-2 at 382 K. It is believed that conjugated polymers with a low bandgap are promising in the field of organic thermoelectric materials.

5.
Ecotoxicol Environ Saf ; 220: 112395, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34102394

RESUMO

Copper (Cu), one of the heavy metals, is far beyond the carrying capacity of the environment with Cu mining, industrial wastewater discharging and the use of Cu-containing pesticides. Intaking excess Cu can cause toxic effects on liver, kidney, heart, but few studies report Cu toxicity on brain tissue. It is noteworthy that most toxicity tests are based on rodent models, but large mammals chosen as animal models has no reported. To explore the relationship of the Cu toxicity and mitochondria-mediated apoptosis on hypothalamus in pigs, the content of Cu, histomorphology, mitochondrial related indicators, apoptosis, and AMPK-mTOR signaling pathway were detected. Results showed that Cu could accumulate in hypothalamus and lead to mitochondrial dysfunction, evidenced by the decrease of ATP production, activities of respiratory chain complex I-IV, and mitochondrial respiratory function in Cu-treated groups. Additionally, the genes and proteins expression of Bax, Caspase-3, Cytc in treatment group were higher than control group. Furthermore, the protein level of p-AMPK was enhanced significantly and p-mTOR was declined, which manifested that AMPK-mTOR signaling pathway was activated in Cu-treated groups. In conclusion, this study illuminated that the accumulation of Cu could cause mitochondrial dysfunction, induce mitochondria-mediated apoptosis and activate AMPK-mTOR pathway in hypothalamus.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Cobre/toxicidade , Hipotálamo/efeitos dos fármacos , Metais Pesados/toxicidade , Mitocôndrias/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Animais , Apoptose , Caspase 3/metabolismo , Cobre/metabolismo , Citocromos c/metabolismo , Exposição Ambiental , Hipotálamo/metabolismo , Metais Pesados/metabolismo , Mitocôndrias/metabolismo , Modelos Animais , Transdução de Sinais , Suínos , Proteína X Associada a bcl-2/metabolismo
6.
J Anim Physiol Anim Nutr (Berl) ; 105(5): 908-915, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33713505

RESUMO

The purpose of this study was to investigate the effects of diet type (normal or low Ca and P diets) and 25(OH)D3 supplementation (with or with not 2000 IU/kg 25(OH)D3 ) during late gestation on the serum biochemistry and reproductive performance of aged sows and newborn piglets. A total of 40 sows, which are at their 7th parity, were divided into four groups: control group (standard diet), low Ca group, 25(OH)D3 group and low Ca plus 25(OH)D3 group respectively (10 in each group). The blood of sows on day 100 and 114 of gestation and newborn piglets was collected for serum biochemical analyses. Results showed that the reproductive performance of sows was not influenced by diet type or 25(OH)D3 supplementation (p > 0.05). And the addition of 25(OH)D3 to diet low Ca group caused that the content of serum TG in sows on day 100 of gestation was not different from that of the control group (p > 0.05). The addition of 25(OH)D3 significantly decreases the content of serum TG in sows on day 114 of gestation (p < 0.05). The addition of 25(OH)D3 significantly increased the content of serum UREA and CREA in newborn piglets (p < 0.05). Overall, feeding 2000 IU/kg 25(OH)D3 to aged sows at late gestation had no effects on reproductive performance, but partly contributed to keeping serum TG balance in sows and may indicate increased pressure on kidneys in newborn piglets.


Assuntos
Ração Animal , Dieta , Ração Animal/análise , Animais , Animais Recém-Nascidos , Dieta/veterinária , Suplementos Nutricionais , Feminino , Lactação , Paridade , Gravidez , Suínos , Vitamina D/análogos & derivados
7.
Ecotoxicol Environ Saf ; 213: 112040, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33610943

RESUMO

Among different synthetic compounds copper (Cu) is persistently and frequently used as growth promoter, antibacterial, antifungal and antiparasitic agent and has become common environmental pollutant. Therefore, this study explores the cardio-toxic effects of control group (10 mg/kg bw Cu) and treatment group (125 and 250 mg/kg bw Cu), and it association with process of autophagy and metabolomics in myocardium of pigs kept in three different experimental treatments for a period of 80 days. The results of serum biochemical parameters showed a significantly increase in creatinine kinase (CK), creatine kinase-MB (CK-MB), high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C) and aspartate aminotransferase (AST) in pigs exposed to 125 mg/kg bw and 250 mg/kg bw Cu. Meanwhile, the severe structural abnormalities in cardiomyocytes were found when exposed to 250 mg/kg Cu at day 80. In addition, the mRNA and proteins (Beclin1, ATG5 and LC3II) expression levels were significantly increased and p62 was significantly decreased in cardiomyocytes exposed to 250 mg/kg Cu at day 80 of the trial. Further, UPLC-QTOF/MS technique showed that 7 metabolites were up-regulated and 37 metabolites were down-regulated in cardiomyocytes after 250 mg/kg Cu treatment, with a principal impact on the metabolic pathways including glycerophospholipid metabolism, one carbon pool by folate, fatty acid elongation and fatty acid degradation, which were related to autophagy. Overall, our study identified the autophagy processes and metabolites in metabolic pathways in Cu-induced myocardium injury, which provided useful evidence of myocardium toxicity caused by Cu exposure via metabolomics and multiple bioanalytic methods.


Assuntos
Autofagia/efeitos dos fármacos , Cobre/toxicidade , Poluentes Ambientais/toxicidade , Coração/efeitos dos fármacos , Animais , Poluentes Ambientais/metabolismo , Coração/fisiologia , Redes e Vias Metabólicas , Metabolômica , Miocárdio/metabolismo , Suínos
8.
Environ Technol ; : 1-10, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33086947

RESUMO

ABSTRACTThe use of ammonium iron (II) sulphate ((NH4)2Fe(SO4)2) to remediate soil contaminated with Cr (VI) was assessed. (NH4)2Fe(SO4)2 effectively remediated soil contaminated with Cr (VI) and, acted as a fertilizer by supplying nitrogen because it contains ammonium. The effects of the (NH4)2Fe(SO4)2 dose, water content, pH of the soil and the contact time were investigated. The amount of Cr (VI) leached from the most-polluted soil, determined using a leaching toxicity procedure using optimized conditions, was 347.64 mg kg-1 when the soil was untreated and 6.74 mg kg-1 when the soil was treated with (NH4)2Fe(SO4)2. Bio-utilizable Cr contributed 59.44% and 0.16% of the total Cr contents of the untreated and treated soil, respectively. The relatively stable Cr species contributed 24.92% and 98.38% of the total Cr contents of the untreated and treated soil, respectively. The results indicated that adding (NH4)2Fe(SO4)2 markedly decreased the risk of Cr being released from heavily contaminated soil by decreasing the availability of Cr in the soil. Overall, the results indicated that adding (NH4)2Fe(SO4)2 causes some Cr (VI) in contaminated soil to be reduced to Cr (III), and to form a precipitate, which decreases the risk of Cr being released. (NH4)2Fe(SO4)2 can be applied to soil contaminated with Cr (VI) on a large scale because it is cheap and simple to achieve.

9.
Neuroreport ; 31(11): 806-813, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32576768

RESUMO

Post-stroke cognitive impairment (PSCI) severely affects the quality of a survivor's life, but its neurophysiological basis remains unknown. Neuroinflammation has been considered as an important contributor to PSCI, which could be induced or exacerbated by system inflammation. NACHT-LRR- and pyrin-domain-containing protein 3 (NLRP3) inflammasome is the most widely studied in the initiation of inflammation. Here, using a mouse model of photothrombotic stroke, we demonstrated that NLRP3 activation plays a critical role in PSCI. Intraperitoneal injection of the lipopolysaccharide-activated NLRP3 inflammasome, exacerbated the microglial activation and decreased the number of neurons, impaired the hippocampal neurogenesis, eventually aggravated PSCI. Intraperitoneal injection of MCC950 inhibited the NLRP3 activation, decreased the number of microglia, increased the number of neurons and promoted the hippocampal neurogenesis, eventually improved PSCI. Our results identified NLRP3 inflammasome as an important modifier of neuropathology in PSCI, which could be a could be a potential therapeutic target for PSCI treatment.


Assuntos
Disfunção Cognitiva/imunologia , Inflamassomos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Neurogênese/fisiologia , Acidente Vascular Cerebral/imunologia , Animais , Disfunção Cognitiva/metabolismo , Modelos Animais de Doenças , Furanos/farmacologia , Indenos/farmacologia , Inflamassomos/efeitos dos fármacos , Inflamassomos/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Neurogênese/efeitos dos fármacos , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia , Sulfonamidas/farmacologia
10.
Nano Lett ; 20(3): 1676-1685, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-31995388

RESUMO

Exciton polaritons (EPs) are partial-light partial-matter quasiparticles in semiconductors demonstrating striking quantum phenomena such as Bose-Einstein condensation and single-photon nonlinearity. In these phenomena, the governing process is the EP relaxation into the ground states upon excitation, where various mechanisms are extensively investigated with thermodynamic limits. However, the relaxation process becomes drastically different and could significantly advance the understanding of EP dynamics for these quantum phenomena, when excited states of EPs are involved. Here, for the first time, we observe nonlinear optical responses at the EP excited states in a monolayer tungsten disulfide (WS2) microcavity, including dark excited states and dynamically metastable upper polariton bands. The nonlinear optics leads to unique emissions of ground states with prominent valley degree of freedom (DOF) via an anomalous relaxation process, which is applicable to a wide range of semiconductors from monolayer transition metal dichalcogenides (TMDs) to emerging halide perovskites. This work promises possible approaches to challenging experiments such as valley polariton condensation. Moreover, it also constructs a valley-dependent solid-state three-level system for terahertz photonics and stimulated Raman adiabatic passage.

11.
Proc Natl Acad Sci U S A ; 116(41): 20274-20279, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31548414

RESUMO

The condensation of half-light half-matter exciton polaritons in semiconductor optical cavities is a striking example of macroscopic quantum coherence in a solid-state platform. Quantum coherence is possible only when there are strong interactions between the exciton polaritons provided by their excitonic constituents. Rydberg excitons with high principal value exhibit strong dipole-dipole interactions in cold atoms. However, polaritons with the excitonic constituent that is an excited state, namely Rydberg exciton polaritons (REPs), have not yet been experimentally observed. Here, we observe the formation of REPs in a single crystal CsPbBr3 perovskite cavity without any external fields. These polaritons exhibit strong nonlinear behavior that leads to a coherent polariton condensate with a prominent blue shift. Furthermore, the REPs in CsPbBr3 are highly anisotropic and have a large extinction ratio, arising from the perovskite's orthorhombic crystal structure. Our observation not only sheds light on the importance of many-body physics in coherent polariton systems involving higher-order excited states, but also paves the way for exploring these coherent interactions for solid-state quantum optical information processing.

12.
Nano Lett ; 19(10): 7100-7105, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31518139

RESUMO

Single photon emitters (SPEs) are critical building blocks needed for quantum science and technology. For practical applications, room-temperature solid-state platforms are critically demanded. To scale up quantum information processing using, for example, wavelength division multiplexing quantum key distribution, a large tuning range beyond emission line width of single photon energy is required. Stark effect can tune the single photon energy by an electric field. However, it has been achieved only at cryogenic temperature to pursue a shift larger than emission line width. A large Stark tuning beyond emission line width at room temperature still remains elusive. Here we report the first room-temperature Stark effect of SPEs with a giant Stark shift of single photon energy up to 43 meV/(V/nm), largest among all previous color center emitters. Such a giant Stark shift is 4-fold larger than its line width at room temperature, demonstrated by exploiting hBN color centers. Moreover, the intrinsic broken symmetries are determined via angle-resolved Stark effect, for the first time, by the orientation of the electric permanent dipole moment in the solid-state SPE, which is unachievable in traditional optical polarization measurement. The remarkable Stark shift discovered here and the significant advance in understanding its atomic structure pave a way toward the scalable solid-state on-chip quantum communication and computation at room temperature.

13.
Phys Rev Lett ; 119(2): 027403, 2017 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-28753353

RESUMO

Monolayer transition metal dichalcogenides (TMD) with confined 2D Wannier-Mott excitons are intriguing for the fundamental study of strong light-matter interactions and the exploration of exciton polaritons at high temperatures. However, the research of 2D exciton polaritons has been hindered because the polaritons in these atomically thin semiconductors discovered so far can hardly support strong nonlinear interactions and quantum coherence due to uncontrollable polariton dynamics and weakened coherent coupling. In this work, we demonstrate, for the first time, a precisely controlled hybrid composition with angular dependence and dispersion-correlated polariton emission by tuning the polariton dispersion in TMD over a broad temperature range of 110-230 K in a single cavity. This tamed polariton emission is achieved by the realization of robust coherent exciton-photon coupling in monolayer tungsten disulphide (WS_{2}) with large splitting-to-linewidth ratios (>3.3). The unprecedented ability to manipulate the dispersion and correlated properties of TMD exciton polaritons at will offers new possibilities to explore important quantum phenomena such as inversionless lasing, Bose-Einstein condensation, and superfluidity.

14.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): m798, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22719347

RESUMO

In the complex cation of the title compound, [Mn(C(7)H(5)O(4))(C(12)H(8)N(2))(2)(H(2)O)](C(7)H(5)O(4))·0.5H(2)O, the Mn(II) atom has a six-coordinate octa-hedral environment defined by one carboxyl-ate O atom belonging to a 2,6-dihy-droxy-benzoate (DHB) ligand, four N atoms from two chelating 1,10-phenanthroline mol-ecules and one water mol-ecule. The lattice water mol-ecule lies on a twofold rotation axis. Intra-molecular O-H⋯O hydrogen bonds are present in the DHB anions and complex cations. Inter-molecular O-H⋯O hydrogen bonds link two cations, two anions and one water mol-ecule into a dimer. π-π inter-actions between the pyridine and benzene rings and between the benzene rings are also observed [centroid-centroid distances = 3.7774 (16), 3.7912 (16) and 3.7310 (17) Å].

15.
J Phys Chem B ; 114(27): 8910-6, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20572645

RESUMO

The adsorption behavior of zwitterionic surfactant dodecyl sulfobetaine (DBS) on a silica/solution interface with Ca(2+), Mg(2+) existing in aqueous solution is explored by atomistic molecular simulations. The interaction energy contribution of van der Waals and electrostatic potentials in the surfactants/water/silica system are respectively calculated, from which the electrical interaction can be found to play a decisive role in the adsorption tendency of DBS on the silica surface with or without inorganic ions, despite different mechanisms. The distinct decrease of energy has been found to be derived from electrical interaction when DBS adsorb on the silica surface covered by Ca(2+) or Mg(2+). Therefore, it can be predicted that the cationic ions combined on the negatively charged silica surface in a mineral water medium might decrease the adsorption trend of DBS on the silica surface, which has been experimentally proven by TOC measurement. Structural information of the close interface layer and the distribution of water molecules are analyzed after the complete molecular dynamics simulation using a ternary model. Ca(2+) and Mg(2+) combined on the silica surface can reduce the adsorption amount of DBS by preventing the direct interaction between DBS and surface, and bringing about the orientation reversal of DBS molecules to break the order of adsorption interface layer. Furthermore, changes in the status of the water spreading on the silica surface caused by the complexation of cations are also an important reason in the adsorption reduction.

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