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Photodetectors (PDs) with broadband photoresponse can meet the demand for multiband detection in complex environments, overcoming the technological complexity issue of integrated narrow-band PDs. Self-powered heterojunction PDs having ultraviolet-visible-near-infrared broadband photoresponse were constructed by using SnO2 nanopillars and CuInS2 nanoflakes. The dimension, crystalline quality, and energy level structure of the SnO2 nanopillars were regulated by changing the concentration of Sn ions in the precursor solution. The optimized interfacial energy band structure of the heterojunction can increase the transfer ability of the photogenerated carrier. The optimum performance is achieved for the CuInS2/SnO2(0.025M) PD prepared at 0.025 M Sn ion concentration in the precursor solution with the responsivities of 1.15, 6.13, and 1.02 mA/W, and detectivities of 1.19 × 1010, 6.35 × 1010, and 1.02 × 1010 Jones under 254 nm solar-blind ultraviolet light, 475 nm visible light, and 940 nm near-infrared light. Furthermore, a proof-of-concept solar-blind ultraviolet-visible-near-infrared encrypted communication system utilizing a broadband self-powered CuInS2/SnO2 PD as the receiving terminal and solar-blind ultraviolet light, ultraviolet light, visible light, and near-infrared light as the carrier and encryption protocol is proposed. The PD has great potential for applications in the field of encrypted optical communication.
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In this work, we report the design and fabrication of self-powered binary response PDs based on II-type heterostructures consisting of SnSx nanoflakes (NFs) and rutile TiO2 nanorod arrays (NRs). The TiO2 NRs effectively block light with wavelengths below 400 nm from reaching SnSx. Under 385 nm light, the photoelectrons in TiO2 recombine with holes in SnSx at the interface due to the energy band bending, resulting in a positive photocurrent. Under 410 nm light, the photoelectrons in SnSx and the photogenerated holes in TiO2 accumulate at the interface, overcoming the interfacial potential barriers induced by the higher Fermi levels of SnSx and inducing a negative photocurrent. Based on the bipolar response, the dual-band imaging capability without external filters and the light-encrypted OR, AND, and NOT logic gates using a single device are demonstrated. This work provides a blueprint for the development of multifunctional self-powered PDs that can simplify system architecture, reduce the energy consumption, and improve accuracy for applications, such as visual systems, light-controlled logic circuits, and encrypted optical communications.
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BACKGROUND AND PURPOSE: Alcoholic liver disease (ALD), a metabolic liver disease caused by excessive alcohol consumption, has attracted increasing attention due to its high prevalence and mortality. Up to date, there is no effective and feasible treatment method for ALD. This study was to investigate whether Farnesoid X receptor (FXR, NR1H4) can alleviate ALD and whether this effect is mediated by inhibiting absent in melanoma 2 (AIM2) inflammasome activation. METHODS: The difference in FXR expression between normal subjects and ALD patients was analyzed using the Gene Expression Omnibus (GEO) database. Lieber-DeCarli liquid diet with 5% ethanol (v/v) (EtOH) was adopted to establish the mouse ALD model. Liver histopathological changes and the accumulation of lipid droplets were assessed by H&E and Oil Red O staining. Quantitative real-time PCR, Western blotting analysis and immunofluorescence staining were utilized to evaluate the expression levels of related genes and proteins. DCFH-DA staining was adopted to visualize reactive oxidative species (ROS). RESULTS: FXR was distinctly downregulated in liver tissues of patients with steatosis compared to normal livers using the GEO database, and in ethanol-induced AML-12 cellular steatosis model. FXR overexpression ameliorated hepatic lipid metabolism disorder and steatosis induced by ethanol by inhibiting the expression of genes involved in lipid synthesis and inducing the expression of genes responsible for lipid metabolism. Besides, FXR overexpression inhibited ethanol-induced AIM2 inflammasome activation and alleviated oxidative stress and ROS production during ethanol-induced hepatic steatosis. However, when FXR was knocked down, the results were completely opposite. CONCLUSIONS: FXR attenuated lipid metabolism disorders and lipid degeneration in alcohol-caused liver injury and alleviated oxidative stress and inflammation by inhibiting AIM2 inflammasome activation.
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Fígado Gorduroso , Hepatopatias Alcoólicas , Melanoma , Animais , Humanos , Camundongos , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Etanol/efeitos adversos , Etanol/metabolismo , Fígado Gorduroso/etiologia , Inflamassomos/efeitos adversos , Inflamassomos/metabolismo , Lipídeos , Fígado/patologia , Hepatopatias Alcoólicas/prevenção & controle , Hepatopatias Alcoólicas/genética , Espécies Reativas de Oxigênio/metabolismoRESUMO
Oxidative stress-mediated activation of inflammasome has a significant effect on the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Farnesoid X receptor (NR1H4, FXR) has been implicated in biological function and many diseases, including NAFLD. The regulatory effect of FXR on oxidative stress and whether this process is related with the activation of absent melanoma 2 (AIM2) inflammasome in NAFLD remain unclear. In the present research, we confirmed that FXR in the livers of steatosis patients is significantly reduced compared with normal liver tissue by using the Gene Expression Omnibus (GEO) database and a palmitic acid (PA) - mediated steatosis model in AML-12 cells. Under the premise of ensuring the same food intake as the control group, overexpression of FXR in mice attenuated HFD-mediated weight gain and liver steatosis, facilitated lipid metabolism, improved fatty acid ß-oxidation, lipolysis, and reduced fatty acid synthesis and intake, which also inhibited the activation of AIM2 inflammasome. Overexpression of FXR alleviated PA-induced triglyceride (TG) accumulation, imbalance of lipid homeostasis, and the activation of AIM2 inflammasome in hepatic steatosis cells, while FXR knockdown appeared the opposite effects. FXR overexpression suppressed PA- and HFD-induced oxidative stress, but FXR siRNA demonstrated the opposite influence. The decreased ROS generation may be the reason why FXR weakens AIM2 activation when a fatty acid overload occurs. In conclusion, our results confirm that other than regulating lipid homeostasis and blocking NLRP3 inflammasome activation, FXR improves hepatic steatosis by a novel mechanism that inhibits oxidative stress and AIM2 inflammasome activation.
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Melanoma , Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Camundongos , Proteínas de Ligação a DNA/genética , Inflamassomos/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Ácido PalmíticoRESUMO
In this paper, self-powered photodetectors (PDs) with a dual-band photoresponse and excellent photodetection capabilities in complex environments can meet the needs of diverse detection targets, complex environments and diverse tasks. Herein, Bi2O3 nanosheets were deposited on the surface of TiO2 nanorod arrays (NRs) by chemical bath deposition (CBD) to construct self-powered heterojunction PDs with a UV-blue dual-band photoresponse. The nucleation and growth of Bi2O3 nanosheets on TiO2 NRs substrates were controlled by varying the concentration of the complexing agent triethanolamine (TEA) in the precursor solution, which regulated the morphology, crystalline quality and energy band structure as well as the photoelectronic properties of Bi2O3 films. The devices fabricated at a TEA concentration of 0.3 M exhibited excellent self-powered UV-blue dual-band photoresponse characteristics, achieving a photocurrent (Iph) of 144 nA, a responsivity of 1.79 mA W-1 and a detectivity of 5.94 × 1010 Jones under 405 nm illumination at 0 V, which can be attributed to the large built-in electric field (Eb) of Bi2O3/TiO2 heterojunctions, the low interfacial transfer resistance and suitable carrier transport path. In addition, Bi2O3/TiO2 heterojunction PDs with the UV-blue dual-band photoresponse characteristics can be applied in UV-encrypted visible light communication (VLC) with a light-controlled logic gate to improve the security of information transmission.
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One-dimensional (1D) metal oxides with excellent carrier transport and light absorption properties can be applied to photodetectors (PDs), facilitating device miniaturization, portability, and integration. Surface modification of 1D semiconductors can reduce carrier recombination in PDs as a way to increase photocurrent and decrease dark current of PDs. Herein, ultrathin BaTiO3 (BTO) shell layers are grown on the surface of TiO2 nanorod arrays (NRs) by in situ conversion using hydrothermal reaction, and the self-powered TiO2-BTO NRs PDs are constructed. The effect of the thickness of BTO shell layers on the photoresponse characteristics of self-powered TiO2-BTO NRs PDs is investigated by controlling the Ba2+ conversion concentration. The results show that the BTO shell layer reduces the dark current of the PDs because of the decreased interfacial transfer resistance and improved transfer of photogenerated carriers for building a "bridge" of carrier transport between BTO and TiO2 due to the formation of Ti-O-Ti bonds. Moreover, the presence of the spontaneous polarization electric field in BTO enhances the photocurrent and response speed of PDs. The self-powered TiO2-BTO NRs PDs are integrated in series and parallel to realize the functions of "and" and "or" gates of light-controlled logic gates. The ability to convert light signals into electrical signals for the self-powered PDs in real time demonstrates its great potential for optoelectronic interconnection circuits, which has important application prospects in the field of optical communication.
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Molecular surface reconfiguration strategies have been instrumental to performance improvements of halide perovskite photovoltaic applications in recent years. However, research into the optical properties of the lead-free double perovskite Cs2AgInCl6 on the complex reconstructed surface is still lacking. Here, blue-light excitation in double perovskite Cs2Na0.4Ag0.6InCl6 with Bi doping has been successfully achieved by excess KBr coating and ethanol-driven structural reconstruction. Ethanol drives the formation of hydroxylated Cs2-yKyAg0.6Na0.4In0.8Bi0.2Cl6-yBry in the Cs2Ag0.6Na0.4In0.8Bi0.2Cl6@xKBr interface layer. The hydroxyl group adsorbed on the interstitial sites of the double perovskite structure induces a transfer of local space electrons to the [AgCl6] and [InCl6] octahedral regions, enabling them to be excited with blue light (467 nm). The passivation of KBr shell reduces the non-radiative transition probability of excitons. Blue-light-excited flexible photoluminescence devices based on hydroxylated Cs2Ag0.6Na0.4In0.8Bi0.2Cl6@16KBr are fabricated. The application of hydroxylated Cs2Ag0.6Na0.4In0.8Bi0.2Cl6@16KBr as down-shift layer in GaAs photovoltaic cell module can increase its power conversion efficiency by 3.34%. The surface reconstruction strategy provides a new way to optimize the performance of lead-free double perovskite.
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As a result of the apparent hysteresis caused by ion migration, halide perovskites (HPs) are used as the active layer of resistive devices. Here, polyethylene glycol (PEG) is used to form an organic network in the Cs3Bi2Br9 precursor solution to influence the nucleation growth rate of the substrate and, thus, control the perovskite surface morphology, crystallization process, and halide ion migration activation energy. Furthermore, the organic network consisting of non-conducting polymer PEG rests on the boundaries between perovskite crystals to cross-link perovskite particles. As a result, the particle size of perovskite increased from 64.6 to 76.2 nm as the nucleation rate of perovskite gradually decreased with the increase of the PEG concentration and the activation energy of the ion increases from 0.15 to 0.25 eV. Meanwhile, as the concentration of PEG increases, the switching ratio and cycle stability of the devices is improved.
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Hydrotalcite, first found in natural ores, has important applications in supercapacitors. NiCoAl-LDH, as a hydrotalcite-like compound with good crystallinity, is commonly synthesized by a hydrothermal method. Al3+ plays an important role in the crystallization of hydrotalcite and can provide stable trivalent cations, which is conducive to the formation of hydrotalcite. However, aluminum and its hydroxides are unstable in a strong alkaline electrolyte; therefore, a secondary alkali treatment is proposed in this work to produce cation vacancies. The hydrophilicity of the NiCoAl-OH surface with cation vacancy has been greatly improved, which is conducive to the wetting and infiltration of electrolyte in water-based supercapacitors. At the same time, cation vacancies generate a large number of defects as active sites for energy storage. As a result, the specific capacity of the NiCoAl-OH electrode after 10,000 cycles can be maintained at 94.1%, which is much better than the NiCoAl-LDH material of 74%.
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Nonalcoholic fatty liver disease (NAFLD), a metabolic disease, has received wide attention worldwide. However, there is no approved effective drug for NAFLD treatment. In the study, H&E and Oil Red O staining were employed to detect liver histopathological changes and the accumulation of lipid droplets. Quantitative real-time PCR, Western blot, bioinformatics, luciferase assay, immunofluorescence staining, reactive oxygen species (ROS), and siRNA were used to further elucidate the mechanism of isoliquiritigenin (ISL) against NAFLD. The results showed that ISL significantly reduced the liver-to-body weight ratios and biochemical index. And the staining results showed that ISL remarkedly ameliorated liver histopathological changes of NAFLD. Furthermore, ISL significantly increased the levels of PPARα, CPT1α, and ACADS, which were involved in lipid metabolism, and inhibited the ROS, TNF-α, IL-1ß, and IL-6 expression by activating PGC-1α. Bioinformatics and luciferase assay analysis confirmed that miR-138-5p might bind to PGC-1α mRNA in NAFLD. Importantly, the expression of miR-138-5p was increased in the NAFLD, which was significantly decreased by ISL. In addition, the miR-138-5p inhibitor also promoted lipid metabolism and inhibited inflammatory response in NAFLD via PGC-1α activation. The above results demonstrate that ISL alleviates NAFLD through modulating miR-138-5p/PGC-1α-mediated lipid metabolism and inflammatory reaction in vivo and in vitro.
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Chalconas , MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Animais , Chalconas/farmacologia , Regulação para Baixo , Humanos , Fígado , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismoRESUMO
BACKGROUND: Alcoholic liver disease (ALD), one of the most prevalent forms of liver disease, has received wide attention worldwide. However, limited efficient and appropriate therapeutic agents were responded to ALD. Isoliquiritigenin (ISL), a flavonoid isolated from liquorice, possesses multiple pharmacological activities. PURPOSE: The current study investigated the hepatoprotective effect of ISL against ALD and further elucidate the involvement of miR-23a-3p/peroxisome proliferative activated receptor-γ coactivator 1 alpha (PGC-1α) in vivo and in vitro experiments. STUDY DESIGN AND METHODS: In the study, H&E and Oil Red O staining were employed to detect liver histopathological changes and the accumulation of lipid droplets. Quantitative real-time PCR, bioinformatics, luciferase assay, immunofluorescence staining, reactive oxygen species (ROS), Western blot, and siRNA were used to further explore the mechanism of ISL protection. RESULTS: ISL significantly reduced the liver-to-body weight ratios and biochemical index. The staining results showed that ISL remarkedly ameliorated the histopathological changes in the liver. Furthermore, ISL promoted fatty acid metabolism via induction in the expression of PGC-1α-target genes PPARα, CPT1α, and ACADs, and inhibited the ROS, TNF-α, IL-1ß, and IL-6 expression. Bioinformatics and Luciferase assay analysis confirmed that miR-23a-3p might bind to PGC-1α mRNA in ALD. Significantly, the expression of miR-23a-3p was increased in the ALD, which was significantly decreased by ISL. In addition, the miR-23a-3p inhibitor also promoted lipid metabolism in ALD via PGC-1α activation. CONCLUSIONS: We first demonstrated that ISL could alleviate ALD, and further verified that ISL exerted protective effects through modulating miR-23a-3p/PGC-1α-mediated lipid metabolism in vivo and in vitro.
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Chalconas , MicroRNAs , Chalconas/farmacologia , Fígado/metabolismo , MicroRNAs/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
Acute liver failure (ALF) is a dramatic liver disease characterized by large areas of inflammation. However, there are no available effective targeted drugs for ALF treatment. In the study, serum biochemical index and H&E were used to explore the amelioration of the liver histopathological changes. The oxidative stress kits, quantitative real-time PCR, western blot, immunohistochemistry, immunofluorescence staining, reactive oxygen species (ROS), and siRNA were used to elucidate the mechanisms underlying isoliquiritigenin (ISL) protection. The results showed that ISL significantly improved the liver pathological changes. Furthermore, ISL reduced oxidative stress by altering the expression of PGC-1α, Nrf2, HO-1, NQO1, Keap1, GCLC, and GCLM in damaged hepatocytes. Moreover, the levels of inflammation-related genes including NLRP3 inflammasome, IL-1ß, IL-6, TNF-α, iNOS, and Mip-2 were repressed by ISL. In addition, ISL alleviated LPS/D-GalN-induced hepatocytes apoptosis by increasing the Bcl-2/Bax ratio and suppressing the expression of cleaved caspase-3. Further in vivo and in vitro evidence proved the involvement of the PGC-1α/Nrf2 signaling pathway in ISL protection. In conclusion, ISL improves the ability of anti-oxidative stress, alleviates inflammatory reaction, apoptosis, and inhibits NLRP3 inflammasome to protect lipopolysaccharide/D-galactosamine (LPS/D-GalN)-induced ALF through activating the PGC-1α/Nrf2 pathway, which provides the possibility for the treatment of ALF.
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Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Chalconas/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Mediadores da Inflamação/metabolismo , Falência Hepática Aguda/prevenção & controle , Fígado/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Modelos Animais de Doenças , Galactosamina , Inflamassomos/genética , Inflamassomos/metabolismo , Lipopolissacarídeos , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Falência Hepática Aguda/imunologia , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/patologia , Masculino , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Transdução de SinaisRESUMO
BACKGROUND: Alcoholic liver disease (ALD) is a progressive disease beginning with simple steatosis but can progress to alcoholic steatohepatitis, fibrosis, cirrhosis, and even hepatocellular carcinoma. The morbidity of ALD is on the rise and has been a large burden on global healthcare system. It is unfortunately that there are currently no approved therapeutic drugs against ALD. Hence, it is of utmost urgency to develop the efficacious therapies. The ability of many molecular targets against ALD is under investigation. Farnesoid X receptor (FXR), a member of the ligand-activated transcription factor superfamily, has been recently demonstrated to have a crucial role in the pathogenesis and progression of ALD. PURPOSE: The purpose of the study is to determine whether Yangonin (YAN), a FXR agonist previously demonstrated by us, exerts the hepatoprotective effects against ALD and further to clarify the mechanisms in vitro and in vivo. STUDY DESIGN: The alcoholic liver disease model induced by Lieber-Decarli liquid diet was established with or without Yan treatment. METHODS: We determined the liver to body weight ratios, the body weight, serum and hepatic biochemical indicators. The alleviation of the liver histopathological progression was evaluated by H&E and immunohistochemical staining. Western blot and quantitative real-time PCR were used to demonstrate YAN treatment-mediated alleviation mechanisms of ALD. RESULTS: The data indicated that YAN existed hepatoprotective activity against ALD via FXR activation. YAN improved the lipid homeostasis by decreasing hepatic lipogenesis and increasing fatty acid ß-oxidation and lipoprotein lipolysis through modulating the related protein. Also, YAN ameliorated ethanol-induced cholestasis via inhibiting bile acid uptake transporter Ntcp and inducing bile acid efflux transporter Bsep and Mrp2 expression. Besides, YAN improved bile acid homeostasis via inducing Sult2a1 expression and inhibiting Cyp7a1 and Cyp8b1 expression. Furthermore, YAN attenuated ethanol-triggered hepatocyte damage by inhibiting cellular senescence marker P16, P21 and Hmga1 expression. Also, YAN alleviated ethanol-induced inflammation by down-regulating the inflammation-related gene IL-6, IL-1ß and TNF-α expression. Notably, the protective effects of YAN were cancelled by FXR siRNA in vitro and FXR antagonist GS in vivo. CONCLUSIONS: YAN exerted significant hepatoprotective effects against liver injury triggered by ethanol via FXR-mediated target gene modulation.
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Senescência Celular , Colestase , Metabolismo dos Lipídeos , Hepatopatias Alcoólicas , Pironas/farmacologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Ácidos e Sais Biliares , Homeostase , Fígado , Hepatopatias Alcoólicas/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Surface decoration of noble-metal cocatalysts on graphitic phase carbon nitride (g-C3N4) with high efficiency and trace content for water splitting is exciting but difficult to achieve. Herein, we report the anchoring of Au and metallic/oxidized Pt nanoparticles (NPs) on g-C3N4 as cocatalysts via a photoreduction process for enhancing photocatalytic H2 production. Au NPs are preferentially decorated on g-C3N4, which can control the formation of metallic/oxidized Pt complex species. The well dispersed Au and metallic/oxidized Pt NPs improved the light-harvesting and the photo-generated carrier separation of g-C3N4. G-C3N4 sequentially decorated with Au (0.3 wt%) and metallic/oxidized Pt (0.3 wt%) cocatalysts, exhibited the highest and stable H2 evolution rates of 2560 and 139 µmol h-1 g-1 under simulated sunlight and visible light (λ ≥ 420 nm) irradiation, respectively, compared to the samples that are simultaneously and sequentially decorated with the same content of Pt and Au on g-C3N4. The enhanced photocatalytic activity is attributed to the synergistic effect of Au and metallic/oxidized Pt cocatalysts, i.e., the effective localized surface plasma resonance coupling between Pt and Au NPs, as well as electron-sink function of metallic Pt, which promote the generation and transfer of more carriers from g-C3N4 to the Pt species, in addition to the superior hydrogen evolution capacity of metallic and oxidized Pt. This work maximizes the performance of noble-metal cocatalysts with minimized content and provides the possibility of realizing efficient solar-to-fuel conversion.
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A lithium metal anode is regarded as the most promising anode material for the next generation of high-energy density batteries because of its high specific capacity and low reduction potential. However, dendritic deposition and severe side reactions in continuous Li plating/stripping inevitably hinder the practical application of Li metal batteries. A solid polymer electrolyte protective layer with synergistic Li3PO4/polyvinyl alcohol (PVA) features is in situ constructed on a lithium metal anode to obtain a stable interface during charge/discharge cycles. The protective layer can adapt to volume changes and inhibit lithium dendrites. The in situ reaction guaranteed the uniformity of ion transport and a tight interface between the protective layer and the lithium metal, so that the lithium deposition behavior was effectively regulated. The PP-Li anode presented a stable Li plating/stripping for 1000 h in a symmetrical cell system and exhibited an enhanced performance of the lithium titanium oxide cell. The in situ Li3PO4/PVA solid polymer electrolyte protective layer provided a promising strategy to tackle the challenges raised by the intrinsic properties of the lithium metal anode.
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Genome-wide studies have reported that Parkinson's disease is associated with abnormal expression of various growth factors. In this study, male C57BL/6 mice aged 10 weeks were used to establish Parkinson's disease models using an intraperitoneal injection of 60 mg/kg 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. 28 days later, 10 or 100 ng fibroblast growth factor 20 was injected intracerebroventricularly. The electrophysiological changes in the mouse hippocampus were recorded using a full-cell patch clamp. Expression of Kv4.2 in the substantia nigra was analyzed using a western blot assay. Serum malondialdehyde levels were analyzed by enzyme-linked immunosorbent assay. The motor coordination of mice was evaluated using the rotarod test. The results showed that fibroblast growth factor 20 decreased A-type potassium current in neurons of the substantia nigra, increased long-term potentiation amplitude in the hippocampus, and downregulated Kv4.2 expression. A high dose of fibroblast growth factor 20 reduced serum malondialdehyde levels and enhanced the motor coordination of mice. These findings confirm that fibroblast growth factor 20 has a therapeutic effect on the toxicity induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, and its mechanism of action is associated with the inhibition of A-type K+ currents and Kv4.2 expression. All animal procedures were approved by the Animal Care and Use Committee of Qilu Hospital of Shandong University, China in 2017 (approval No. KYLL-2017-0012).
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In cereal crops, ABA deficiency during seed maturation phase causes pre-harvest sprouting (PHS), and molybdenum cofactor (MoCo) is required for ABA biosynthesis. Here, two rice PHS mutants F254 and F5-1 were characterized. In addition to the PHS, these mutants showed pleiotropic phenotypes such as twisting and slender leaves, and then died when the seedling developed to four or five leaves. Map-based cloning showed that OsCNX6 and OsCNX1 encoding homologs of MoaE and MoeA were responsible for F254 and F5-1 mutants, respectively. Genetic complementation indicated that OsCNX6 not only rescued the PHS and seedling lethal phenotype of the cnx6 mutant, but also recovered the MoCo-dependent enzyme activities such as xanthine dehydrogenase (XDH), aldehyde oxidase (AO), nitrate reductase (NR) and sulfite oxidase (SO). Expression pattern showed that OsCNX6 was richly expressed in seed during embryo maturation by quantitative reverse transcriptase PCR and RNA in situ hybridization. Furthermore, the OsCNX6 overexpression plants can significantly enhance the MoCo-dependent enzyme activities, and improved the osmotic and salt stress tolerance without unfavorable phenotypes. Collectively, these data indicated that OsCNX6 participated in MoCo biosynthesis, and is essential for rice development, especially for seed dormancy and germination, and OsCNX6 could be an effective target for improving abiotic stress tolerance in rice.
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Vias Biossintéticas , Coenzimas/biossíntese , Metaloproteínas/biossíntese , Mutação/genética , Oryza/crescimento & desenvolvimento , Oryza/genética , Adaptação Fisiológica , Regulação da Expressão Gênica de Plantas , Cofatores de Molibdênio , Oryza/fisiologia , Osmose , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pteridinas , Estresse Salino/genética , Estresse Fisiológico/genéticaRESUMO
Coupled adsorption and photocatalytic oxidation brings high expectations regarding the fast and efficient removal of gaseous pollutants in air. However, to fabricate an adsorbent-photocatalyst composite, coating of a photocatalyst on adsorbent support inevitably results in loss of adsorption and light blocking on interior surfaces. In this work, we attempt to develop an adsorbent-photocatalyst monolith composite, which not only perfectly retains original high adsorption capacity, but also allows complete penetration of UV light through the whole monolith. We employ a SiO2 aerogel monolith with a diameter of 2.5 cm and thickness of 0.7 cm as adsorbent and support. After atomic layer deposition (ALD) followed by calcination, 0.32-1.25 wt% TiO2 is dispersed on the skeleton of the SiO2 aerogel. In spite of such a low level of loading, the monolith composites exhibit fast and efficient removal of gaseous acetaldehyde and NO. Therein, the best performance is achieved at a loading of 0.6 wt% TiO2. By dark adsorption, the acetaldehyde pollutant with initial concentration of 200 ppm can be adsorbed by 54% within 10 min. Moreover, the light transmittance at 387 nm can be retained as high as 6% after penetrating through the whole monolith, confirming that all loaded TiO2 nanoparticles can participate in the photocatalytic oxidation of acetaldehyde. Under UV irradiation with intensity close to natural sunlight, the preadsorbed acetaldehyde can be completely mineralized into CO2 by photocatalytic oxidation in another 60 min, benefiting from the ultradispersion of TiO2 nanoparticles inside the SiO2 aerogel. The study provides a novel three-dimensional model of an adsorbent-photocatalyst composite for the fast and efficient removal of gaseous pollutants.
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Lectins and antimicrobial peptides (AMPs) are widely distributed in various insects and play crucial roles in primary host defense against pathogenic microorganisms. Two AMPs (cecropin and attacin) have been identified and characterized in the larvae of housefly. In this study, two novel C-type lectins (CTLs) were obtained from Musca domestica, while their agglutinating and antiviral properties were evaluated. Real-time PCR analysis showed that the mRNA levels of four immune genes (MdCTL1, MdCTL2, Cecropin, and Attacin) from M. domestica were significantly upregulated after injection with killed Gram-negative Escherichia coli. Moreover, purified MdCTL1-2 proteins can agglutinate E. coli and Staphylococcus aureus in the presence of calcium ions, suggesting their immune function is Ca2+ dependent. Sequence analysis indicated that typical WND and QPD motifs were found in the Ca2+ -binding site 2 of carbohydrate recognition domain from MdCTL1-2, which was consistent with their agglutinating activities. Subsequently, antiviral experiments indicated that MdCTL1-2 proteins could significantly reduce the infection rate of Spodoptera frugiperda 9 cells by the baculovirus Autographa californica multicapsid nucleopolyhedrovirus, indicating they might play important roles in insect innate immunity against microbial pathogens. In addition, MdCTL1-2 proteins could effectively inhibit the replication of influenza H1 N1 virus, which was similar to the effect of ribavirin. These results suggested that two novel CTLs could be considered a promising drug candidate for the treatment of influenza. Moreover, it is believed that the discovery of the CTLs with antiviral effects in M. domestica will improve our understanding of the molecular mechanism of insect immune response against viruses.
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Cecropinas/metabolismo , Moscas Domésticas/metabolismo , Proteínas de Insetos/metabolismo , Lectinas Tipo C/metabolismo , Animais , Baculoviridae , Moscas Domésticas/genética , Vírus da Influenza A Subtipo H1N1 , Lectinas Tipo C/genética , Lectinas Tipo C/isolamento & purificação , Testes de Sensibilidade Microbiana , Filogenia , Análise de Sequência de DNARESUMO
Doping and tailoring of the crystal orientation are two main strategies to improve the photocatalytic properties of TiO2 films. Herein, we introduce a novel route for obtaining Nb-doped TiO2 anatase films with the [001] preferred orientation by thermal oxidation of the [100]-oriented Nb-doped TiN film prepared by magnetron sputtering. Comprehensive analyses with X-ray diffraction, Raman scattering, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy indicate that the proportion of high-energy (001) facets of the Nb-doped TiO2 film is more than 90% and the Nb5+ ion is successfully doped into the film without destroying the crystallinity and orientation. Moreover, the Nb5+ ion doping significantly restrains the growth of the TiO2 grains and increases the surface roughness, and consequently increases the surface-reactive sites. Therefore, the as-fabricated Nb-doped TiO2 film exhibits efficient photocatalytic oxidation performance for acetaldehyde and oleic acid decomposition under simulated solar light irradiation. Such Nb-doped TiO2 anatase films with high-reactivity (001) facet exposure may find applications in the photocatalysis and solar energy conversion fields.