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1.
Plant J ; 118(1): 263-276, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38078656

RESUMO

Small RNAs play important roles in regulation of plant development and response to various stresses. Northern blot is an important technique in small RNA research. Isotope- and biotin- (or digoxigenin) labeled probes are frequently used in small RNA northern blot. However, isotope-based probe is limited by strict environmental regulation and availability in many places in the world while biotin-based probe is usually suffered from low sensitivity. In this study, we developed a T4 DNA polymerase-based method for incorporation of a cluster of 33 biotin-labeled C in small RNA probe (T4BC33 probe). T4BC33 probe reaches similar sensitivity as 32P-labeled probe in dot blot and small RNA northern blot experiments. Addition of locked nucleic acids in T4BC33 probe further enhanced its sensitivity in detecting low-abundance miRNAs. With newly developed northern blot method, expression of miR6027 and miR6149 family members was validated. Northern blot analysis also confirmed the successful application of virus-based miRNA silencing in pepper, knocking down accumulation of Can-miR6027a and Can-miR6149L. Importantly, further analysis showed that knocking-down Can-miR6027a led to upregulation of a nucleotide binding-leucine rich repeat domain protein coding gene (CaRLb1) and increased immunity against Phytophthora capsici in pepper leaves. Our study provided a highly sensitive and convenient method for sRNA research and identified new targets for genetic improvement of pepper immunity against P. capsici.


Assuntos
Capsicum , MicroRNAs , MicroRNAs/genética , Biotina , Northern Blotting , Isótopos , Capsicum/genética , Doenças das Plantas/genética
2.
Plant Cell Environ ; 47(8): 3181-3197, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38712996

RESUMO

For trees originating from boreal and temperate regions, the dormancy-to-active transition, also known as bud dormancy release and bud break, are crucial processes that allow trees to reactive growth in the spring. The molecular mechanisms underlying these two processes remain poorly understood. Here, through integrative multiomics analysis of the transcriptome, DNA methylome, and proteome, we gained insights into the reprogrammed cellular processes associated with bud dormancy release and bud break. Our findings revealed multilayer regulatory landscapes governing bud dormancy release and bud break regulation, providing a valuable reference framework for future functional studies. Based on the multiomics analysis, we have determined a novel long intergenic noncoding RNA named Phenology Responsive Intergenic lncRNA 1 (PRIR1) plays a role in the activation of bud break. that the molecular mechanism of PRIR1 has been preliminary explored, and it may partially promote bud break by activating its neighbouring gene, EXORDIUM LIKE 5 (PtEXL5), which has also been genetically confirmed as an activator for bud break. This study has revealed a lncRNA-mediated regulatory mechanism for the control of bud break in Populus, operating independently of known regulatory pathways.


Assuntos
Regulação da Expressão Gênica de Plantas , Populus , RNA Longo não Codificante , Populus/genética , Populus/crescimento & desenvolvimento , Populus/fisiologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Dormência de Plantas/genética , Dormência de Plantas/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma , Proteoma/metabolismo , Metilação de DNA
3.
Ren Fail ; 46(2): 2371988, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38952291

RESUMO

AIMS: Abnormal renal lipid metabolism causes renal lipid deposition, which leads to the development of renal fibrosis in diabetic kidney disease (DKD). The aim of this study was to investigate the effect and mechanism of chlorogenic acid (CA) on reducing renal lipid accumulation and improving DKD renal fibrosis. METHODS: This study evaluated the effects of CA on renal fibrosis, lipid deposition and lipid metabolism by constructing in vitro and in vivo models of DKD, and detected the improvement of Notch1 and Stat3 signaling pathways. Molecular docking was used to predict the binding between CA and the extracellular domain NRR1 of Notch1 protein. RESULTS: In vitro studies have shown that CA decreased the expression of Fibronectin, α-smooth muscle actin (α-SMA), p-smad3/smad3, alleviated lipid deposition, promoted the expression of carnitine palmitoyl transferase 1 A (CPT1A), and inhibited the expression of cholesterol regulatory element binding protein 1c (SREBP1c). The expression of Notch1, Cleaved Notch1, Hes1, and p-stat3/stat3 were inhibited. These results suggested that CA might reduce intercellular lipid deposition in human kidney cells (HK2) by inhibiting Notch1 and stat3 signaling pathways, thereby improving fibrosis. Further, in vivo studies demonstrated that CA improved renal fibrosis and renal lipid deposition in DKD mice by inhibiting Notch1 and stat3 signaling pathways. Finally, molecular docking experiments showed that the binding energy of CA and NRR1 was -6.6 kcal/mol, which preliminarily predicted the possible action of CA on Notch1 extracellular domain NRR1. CONCLUSION: CA reduces renal lipid accumulation and improves DKD renal fibrosis by inhibiting Notch1 and stat3 signaling pathways.


Assuntos
Ácido Clorogênico , Nefropatias Diabéticas , Fibrose , Rim , Metabolismo dos Lipídeos , Receptor Notch1 , Fator de Transcrição STAT3 , Transdução de Sinais , Fator de Transcrição STAT3/metabolismo , Receptor Notch1/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Animais , Transdução de Sinais/efeitos dos fármacos , Fibrose/tratamento farmacológico , Ácido Clorogênico/farmacologia , Ácido Clorogênico/uso terapêutico , Humanos , Camundongos , Masculino , Rim/patologia , Rim/efeitos dos fármacos , Rim/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Simulação de Acoplamento Molecular , Camundongos Endogâmicos C57BL , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Linhagem Celular
4.
Nanotechnology ; 34(14)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36260977

RESUMO

All-inorganic cesium lead halide CsPbX3(X = Cl, Br, I) perovskite quantum dots (PQDs) have shown promising potential in current Mini/Micro-LED display applications due to their excellent photoluminescence performance. However, lead ions in PQDs are easily to leak owing to the unstable structure of PQDs, which hinders their commercial applications. Herein, we adopt Rb+ions co-doping strategy to regulate the doping characteristics of Mn2+ions in CsPbCl3PQDs. The synthesized CsPbCl3:(Rb+, Mn2+) PQDs possess enhanced photoluminescence quantum yield of 71.1% due to the reduction of intrinsic defect states and Mn-Mn or Mn-traps in co-doped PQDs. Moreover, the white light emission of CsPb(Cl/Br)3:(Rb+, Mn2+) PQDs is achieved by anion exchange reaction and the constructed WLED exhibits the CIE coordinate of (0.33, 0.29) and the correlated color temperature of 5497 K. Benefiting from the substitution strategy, these doped CsPbX3PQDs can be widely used as fluorescence conversion materials for the construction of Mini/Micro-LED.

5.
Phys Chem Chem Phys ; 25(25): 16866-16871, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37314788

RESUMO

Due to the different sensitivities of the 2E and 4T2 energy levels of Cr3+ to the local environment, Cr3+-doped fluorescent materials appear as excellent candidates for highly sensitive temperature sensing based on luminescence intensity ratio technology. However, a way to broaden the strict Boltzmann temperature measuring range is rarely reported. In this work, through Al3+ alloying strategy, a series of SrGa12-xAlxO19:0.5%Cr3+(x = 0, 2, 4, and 6) solid-solution phosphors were synthesized. Remarkably, the introduction of Al3+ can play a role in regulating the crystal field around Cr3+ and the symmetry of [Ga/AlO6] octahedron, realizing the synchronous tuning of 2E and 4T2 energy levels when the temperature changes in a wide range, achieving the purpose of increasing the intensity difference of 2E → 4A2 and 4T2 → 4A2 transitions, so as to extend the temperature sensing range. Among all samples, SrGa6Al6O19:0.5%Cr3+ showed the widest temperature measuring range from 130 K to 423 K with Sa of 0.0066 K-1 and Sr of 1% K-1@130 K. This work proposed a feasible way to extend the temperature sensing range for transition metal-doped LIR-mode thermometers.

6.
Phys Chem Chem Phys ; 25(2): 1279-1289, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36533449

RESUMO

Perovskites based on CsPbX3 (X = Cl, Br, I) have promising applications in solar cells, light-emitting diodes, and photodetectors. In this paper, the phase stability of inorganic metal halide perovskite CsPbCl3 under hydrostatic pressure and anion substitution is studied using density functional theory (DFT), and this modification is explained by the interaction of the octahedrons and transformation of the bond-orbital coupling. In addition, two space groups, P4/mbm and Amm2, which are stable under stress, are subjected to anion substitution; then, the structural stability and band gap change of CsPbCl3-yXy (X = Br, I; y = 0, 1, 2, 3) are analyzed after applying stress; finally, the electronic structures and optical properties of the six most stable components are presented. The effect of stress and anions on the components' optoelectronic properties is closely linked with the crystal's structural alteration mechanism. These results show that stress and anion modulation can significantly change the optoelectronic properties of materials, which make these materials have broad application prospects. Furthermore, stress can be used as an effective tool for screening the most stable material structure.

7.
Molecules ; 27(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36080195

RESUMO

Tea contains high levels of the compound epigallocatechin gallate (EGCG). It is considered an important functional component in tea and has anti-cancer, antioxidant, and anti-inflammatory effects. The eight phenolic hydroxyl groups in EGCG's chemical structure are the basis for EGCG's multiple biological effects. At the same time, it also leads to poor chemical stability, rendering EGCG prone to oxidation and isomerization reactions that change its original structure and biological activity. Learning how to maintain the activity of EGCG has become an important goal in understanding the biological activity of EGCG and the research and development of tea-related products. Metal-organic frameworks (MOFs) are porous materials with a three-dimensional network structure that are composed of inorganic metals or metal clusters together with organic complexes. MOFs exploit the porous nature of the material itself. When a drug is an appropriate size, it can be wrapped into the pores by physical or chemical methods; this allows the drug to be released slowly, and MOFs can also reduce drug toxicity. In this study, we used MOF Zn(BTC)4 materials to load EGCG and investigated the sustained release effect of EGCG@MOF Zn(BTC)4 and the biological effects on wound healing in a diabetic mouse model.


Assuntos
Catequina , Diabetes Mellitus , Animais , Catequina/análogos & derivados , Catequina/química , Catequina/farmacologia , Camundongos , Chá/química , Cicatrização , Zinco
8.
Anticancer Drugs ; 32(6): 647-656, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33587351

RESUMO

Triple-negative breast cancer (TNBC) is highly aggressive, with high rates of early relapse and very poor overall prognosis. Amphiregulin (AREG) is the most abundant epidermal growth factor receptor (EGFR) agonist in MDA-MB-231 TNBC cells, whose proliferation can be inhibited by (-)-epigallocatechin gallate (EGCG), a constituent of green tea that is prone to oxidative polymerization. The effect of dimeric-EGCG, a dimer of oxidized and polymerized EGCG, on MDA-MB-231 cell the proliferation warrants further exploration. In the present study, MTT, flow cytometry, migration scratch, transwell, western blotting, and surface plasmon resonance assays were used to evaluate the effect of dimeric-EGCG on MDA-MB-231 cells and explore the underlying mechanism. MDA-MB-231 cell proliferation and migration were significantly inhibited by dimeric-EGCG at concentrations as low as 10 µM. Levels of EGFR and p44/42 MAPK phosphorylation in MDA-MB-231 cells were significantly reduced by treatment with 10 µM dimeric-EGCG (P < 0.01). In addition, the levels of phosphorylation induced by exogenous AREG were also inhibited by dimeric-EGCG (P < 0.01); however, no significant effects of dimeric-EGCG were observed on epidermal growth factor or transforming growth factor-alpha signaling. Surface plasmon resonance analysis demonstrated that 10 µM dimeric-EGCG bound directly to the extracellular domain of EGFR, competitively inhibiting the binding of AREG to EGFR. These results suggest a novel mechanism underlying the inhibitory effect of dimeric-EGCG on MDA-MB-231 cells, with potential application in the development of drugs for the treatment of TNBC.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Catequina/análogos & derivados , Anfirregulina/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Catequina/química , Catequina/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dimerização , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Feminino , Humanos , Células MCF-7 , Transdução de Sinais/efeitos dos fármacos
9.
FASEB J ; 33(1): 953-964, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30070931

RESUMO

Delayed wound healing is one of the most prominent clinical manifestations of diabetes and lacks satisfactory treatment options. Persistent inflammation occurs in the late phase of wound healing and impairs the healing process in mice with diabetes mellitus (DM). In this study, we observed that the late wound healing in streptozotocin (STZ)-induced DM mice could be improved by (-)-epigallocatechin gallate (EGCG). The macrophage accumulation, inflammation response, and Notch signaling can be inhibited by EGCG in the skin wounds of DM mice. Furthermore, we found that the LPS-induced inflammation response including overactivated Notch signaling, was inhibited by EGCG in mouse macrophages. Moreover, we confirmed that EGCG could directly bind with mouse Notch-1. In addition, our studies indicated that diabetic wound healing was improved by EGCG treatment before or after the inflammation phase by targeting the Notch signaling pathway, which suggests that the pre-existing diabetic wound healing can be improved by EGCG. To summarize, wound healing can be improved by EGCG through targeting Notch in STZ-induced DM mice. Our findings provide insight into the therapeutic strategy for diabetic wounds and offer EGCG as a novel potential medicine to treat chronic wounds.-Huang, Y.-W., Zhu, Q.-Q., Yang, X.-Y., Xu, H.-H., Sun, B., Wang, X.-J., Sheng, J. Wound healing can be improved by (-)-epigallocatechin gallate through targeting Notch in streptozotocin-induced diabetic mice.


Assuntos
Catequina/análogos & derivados , Diabetes Mellitus Experimental/metabolismo , Receptores Notch/metabolismo , Cicatrização/efeitos dos fármacos , Animais , Catequina/farmacologia , Diabetes Mellitus Experimental/fisiopatologia , Feminino , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Células RAW 264.7 , Transdução de Sinais , Pele/metabolismo , Estreptozocina , Cicatrização/fisiologia
10.
Mol Carcinog ; 58(11): 2065-2076, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31432570

RESUMO

Colorectal cancer (CRC) is one of the most common malignant tumors worldwide. As tumor metastasis is the leading cause of death in patients with CRC, it is important to elucidate the molecular mechanisms that drive CRC metastasis. Studies have shown a close relationship between Iroquois homeobox (IRX) family genes and multiple cancers, while the mechanism by which IRX5 promotes CRC metastasis is unclear. Therefore, we focused on the involvement of IRX5 in CRC metastasis. In this study, analyses of clinical data indicated that the expression of IRX5 was coincided with metastatic colorectal tumors tissues and was negatively correlated with the overall survival of patients with CRC. Functional analysis showed that IRX5 promoted the migration and invasion of CRC cells, accompanied by a large number of cellular protrusions. IRX5-overexpressing cells were more likely to form metastatic tumors in nude mice. Further analysis demonstrated that the core components of the RHOA/ROCK1/LIMK1 pathway were significantly inhibited in IRX5-overexpressing cells. Overexpression of LIMK1 effectively reversed the enhanced cellular motility caused by IRX5 overexpression. Moreover, we found that high levels of IRX5 in intestinal tissues were correlated with the inflammatory response. IRX5 was significantly increased in azoxymethane/dextran sodium sulfate intestinal tissue of mice and IRX5-overexpressing may also enhance chemokines CXCL1 and CXCL8. In summary, our findings suggested that IRX5 promoted CRC metastasis by inhibiting the RHOA-ROCK1-LIMK1 axis, which correlates with a poor prognosis.


Assuntos
Neoplasias Colorretais/genética , Proteínas de Homeodomínio/genética , Inflamação/genética , Fatores de Transcrição/genética , Proteína rhoA de Ligação ao GTP/genética , Animais , Quimiocina CXCL1/genética , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células HT29 , Xenoenxertos , Humanos , Interleucina-8/genética , Intestinos/patologia , Quinases Lim/genética , Masculino , Camundongos , Metástase Neoplásica , Transdução de Sinais/efeitos dos fármacos , Análise Serial de Tecidos , Quinases Associadas a rho/genética
11.
Eur J Nutr ; 56(6): 2037-2048, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27271251

RESUMO

BACKGROUND: Tea polyphenols are the prominent component in tea. After the fermentation process, tea polyphenols are oxidized by polyphenol oxidase to form oxidized tea polyphenols (OTPs). OTPs contain a significant amount of hydrophobic phenyl groups that can bind with non-aqueous materials. Here, we determined whether OTPs can bind with lipids and reduce fat uptake and assessed the effect of OTPs on decreasing obesity and alleviating hyperlipidaemia and other metabolic syndromes. METHODS: Rats were divided into three groups: control, high-fat diet (HFD) and OTP groups. The control and HFD groups were fed a chow diet and a high-fat diet, respectively, for 12 weeks; the OTP group was fed a high-fat diet for 6 weeks and then a high-fat diet containing 2 % OTP for 6 weeks. The serum and excrement triglyceride (TAG) and total cholesterol (CHOL) concentrations were determined, and liver tissue and white adipose tissue were collected to detect the expression levels of genes involved in lipid metabolism. RESULTS: Our results revealed that OTPs failed to decrease the serum concentrations of TAG and CHOL. OTPs alleviated the accumulation of lipids in the liver tissue and changed the expression levels of the regulators of lipid metabolism, i.e., peroxisome proliferation-activated receptors (ppars), compared with the rats fed a high-fat diet alone. We also observed a significantly decreased reduction of weight in the visceral white adipose, enhanced regulation of fatty acid ß-oxidation by PPARα and enhanced biosynthesis of mitochondria in the visceral white adipose of the OTP rats compared with the HFD rats. Additionally, OTPs promoted the excretion of lipids. CONCLUSION: Our results suggest that OTPs alleviate the accumulation of lipids in liver and visceral white adipose tissue and promote lipid excretion in rats in vivo.


Assuntos
Gordura Intra-Abdominal/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Polifenóis/farmacologia , Chá/química , Animais , Biomarcadores/sangue , Colesterol/sangue , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Fezes/química , Hiperlipidemias/sangue , Hiperlipidemias/tratamento farmacológico , Gordura Intra-Abdominal/metabolismo , Fígado/metabolismo , Masculino , Obesidade/sangue , Obesidade/tratamento farmacológico , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Triglicerídeos/sangue
12.
J Sci Food Agric ; 97(6): 1910-1915, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27539359

RESUMO

BACKGROUND: Aflatoxin B1 (AFB1) is the most prevalent and carcinogenic form of the aflatoxins. In this report, we explored the interaction between AFB1 and oxidised tea polyphenols (OTP). Then, the influence of OTP on the absorption and toxicity of AFB1 in rats was investigated. RESULTS: We found that AFB1 can be complexed with OTP, and a transmembrane bidirectional transport experiment verified the absorption of complexed AFB1 (C-AFB1) was inhibited by OTP dramatically (P < 0.001). Animal experiments results showed that the AFB1 plus OTP group had significantly (P < 0.05) decreased AFB1-albumin (AFB1-alb) compared to the AFB1 group at 4 h after ingestion. OTP could significantly (P < 0.01) promote the elimination of AFB1 in faeces. Moreover, the liver injury induced by AFB1 was significantly inhibited by OTP. CONCLUSION: Our results demonstrated AFB1 can be complexed with OTP and the absorption of the C-AFB1 is inhibited in rats. Consequently, the liver injury induced by AFB1 can be inhibited by OTP. These results provide insight that consuming OTP-containing products, like fermented Pu-er tea, can protect damage from AFB1, and OTP may be used as a kind of food additive. © 2016 Society of Chemical Industry.


Assuntos
Aflatoxina B1/metabolismo , Preparações de Plantas/metabolismo , Polifenóis/metabolismo , Chá/metabolismo , Aflatoxina B1/toxicidade , Animais , Células CACO-2 , Humanos , Fígado/metabolismo , Masculino , Oxirredução , Ratos , Ratos Sprague-Dawley , Chá/química
13.
Cell Host Microbe ; 32(9): 1566-1578.e5, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39106871

RESUMO

Viral suppressor RNA silencing (VSR) is essential for successful infection. Nucleotide-binding and leucine-rich repeat (NLR)-based and autophagy-mediated immune responses have been reported to target VSR as counter-defense strategies. Here, we report a protein arginine methyltransferase 6 (PRMT6)-mediated defense mechanism targeting VSR. The knockout and overexpression of PRMT6 in tomato plants lead to enhanced and reduced disease symptoms, respectively, during tomato bush stunt virus (TBSV) infection. PRMT6 interacts with and inhibits the VSR function of TBSV P19 by methylating its key arginine residues R43 and R115, thereby reducing its dimerization and small RNA-binding activities. Analysis of the natural tomato population reveals that two major alleles associated with high and low levels of PRMT6 expression are significantly associated with high and low levels of viral resistance, respectively. Our study establishes PRMT6-mediated arginine methylation of VSR as a mechanism of plant immunity against viruses.


Assuntos
Doenças das Plantas , Imunidade Vegetal , Proteína-Arginina N-Metiltransferases , Solanum lycopersicum , Proteína-Arginina N-Metiltransferases/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Doenças das Plantas/virologia , Doenças das Plantas/imunologia , Solanum lycopersicum/virologia , Solanum lycopersicum/imunologia , Solanum lycopersicum/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/imunologia , Arginina/metabolismo , Metilação , Interferência de RNA , Proteínas Virais/metabolismo , Proteínas Virais/genética , Interações Hospedeiro-Patógeno/imunologia , Regulação da Expressão Gênica de Plantas
14.
J Colloid Interface Sci ; 663: 541-553, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38428112

RESUMO

The CO oxidation catalytic activity of catalysts is strongly influenced by the oxygen vacancy defects (OVDs) concentration and the valence state of active metal. Herein, a defect engineering approach was implemented to enhance the oxygen vacancy defects and to modify the valence of metal ions in manganese oxide octahedral molecular sieves (OMS-2) by the introduction of copper (Cu). The characterization and theoretical calculation results reveal that the incorporation of Cu2+ ion into the OMS-2 structure led to a rise in specific surface area and pore volume, weakening of Mn-O bonds, higher proportion of the low-coordinated oxygen species adsorbed in oxygen vacancies (Oads) and an increase in the average oxidation state of manganese. These structural modifications were discovered to considerably reduce the apparent activation energy (Ea), thus ultimately significantly enhancing the CO oxidation activity (T99 at 148 ℃at GHSV = 13,200 h-1) than the original OMS-2 (T99 = 215 ℃ at GHSV = 13,200 h-1). Furthermore, In-situ diffuse reflectance infrared Fourier transform (DRIFT) and In-situ near-ambient pressure X-ray photoelectron spectroscopy (in situ NAP-XPS) results indicate that the bimetallic synergy enhanced by doping strategy accelerates the conversion of oxygen to chemisorbed oxygen species and the reaction rate of CO oxidation through Mn3++Cu2+↔Mn4++Cu+ redox cycle. The findings of this study offer novel perspectives on the design of catalysts with exceptional performance in CO oxidation.

15.
J Colloid Interface Sci ; 651: 705-713, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37567114

RESUMO

Solar-driven pollutants degradation is an important way for green wastewater treatment, but it is still limited by the intermittent solar flux. Here, we have prepared piezoelectric Bi4Ti3O12 (BTO) nanosheets with abundant physical properties, which can convert extensive solar energy, mechanical energy and temperature variation energy into electrical and chemical energy. It can be used for round-the-clock wastewater treatment by harvesting multi-modal energy. More importantly, the degradation rate of piezoelectric nanosheets can reach 153.4 × 10-3 min-1, and nanosheets can degrade many organic pollutants. In addition, we fabricate porous foam catalysts based on BTO-polydimethylsiloxane (PDMS) composite to prevent secondary contamination. Our results suggest that BTO nanosheets with photoelectric, piezoelectric and pyroelectric catalysis offer a potential approach for round-the-clock wastewater degradation by harvesting solar energy, ambient mechanical energy, and cyclic thermal energy.

16.
Transl Cancer Res ; 11(5): 993-1004, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35706807

RESUMO

Background: Tryptophan catabolism leading to T cell suppression mediated by indoleamine 2,3-dioxygenase (IDO1) is an important mechanism of tumor immune escape, and IDO1 inhibitors have attracted increasing attention as anticancer therapeutics. However, the phase III clinical trial (ECHO-301/KEYNOTE-252) of epacadostat (INCB024360) had disappointing outcomes. This revealed that purification of IDO1 with high purity is one of the major constraints that limit the development of its inhibitors. Methods: Pan-cancer analysis was used to elucidate the relationship between IDO1 function in tumor immunology. The recombinant pET28a-IDO1-strep plasmid and E. coli Rosetta (DE3) strain were used to express and strep-tactin beads to purify the strep-IDO1 protein. High performance liquid chromatography (HPLC) was used to detect enzymatic activity of IDO1. Ten female C57BL/6 mice was used to prepared polyclonal antibody. Enzyme linked immunosorbent assay (ELISA), Western blot, and immunofluorescence were used to measure polyclonal antibody. Results: We described an improved method for the purification of recombinant IDO1 protein based on the strep-tag using an E. coli expression system. We obtained large amount of IDO1 with enhanced purity by employing one-step purification through strep-tactin beads. The polyclonal antibody acquired immunized mice could specifically recognize both recombinant and endogenous IDO1. Conclusions: Purified human strep-IDO1 using the protocol described in our study could be used for further biochemical and structural analyses, which may facilitate functional research and further drug screening study on IDO1.

17.
ISA Trans ; 122: 346-356, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33993994

RESUMO

In this paper, a fixed-time controller under the mechanism of event-trigger is designed for a class of nonlinear pure-feedback systems with non-differentiable non-affine functions. By properly modeling non-affine terms, the limitation of the partial derivatives of non-affine functions is eliminated. In our design process, we first develop a fixed-time adaptive controller using decoupling method. Then, a relative threshold event-trigger mechanism (ETM) is introduced in Section 3.1. The proposed controller can not only stabilize the system within a fixed-time, but also save communication resources more effectively. Lastly, the feasibility of the proposed control scheme is verified by two simulation examples.

18.
Artigo em Inglês | MEDLINE | ID: mdl-35914033

RESUMO

This article solves the cooperative adaptive tracking control problem for nonlinear pure-feedback multi-agent systems (MASs). Compared with the previous achievements of adaptive control of pure-feedback MASs, the partial derivative of the nonaffine function may not exist by using decoupling technology. In the controller design framework based on the backstepping technique, the additional state variables are processed using the special properties of the radial basis function neural networks (RBF NNs). A special-shaped Laplacian matrix is proposed to unify the leader gain form in the tracking error design process (the coefficient in the second term of tracking error). Furthermore, an event trigger mechanism (ETM) is introduced to save resources. The constructed controller under the ETM can not only stabilize the system states but also make the tracking error reach a small accuracy. Finally, the simulation results demonstrated the feasibility of the proposed method.

19.
Nat Cell Biol ; 24(3): 364-372, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35292781

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) originates from normal pancreatic ducts where digestive juice is regularly produced. It remains unclear how PDAC can escape autodigestion by digestive enzymes. Here we show that human PDAC tumour cells use gasdermin E (GSDME), a pore-forming protein, to mediate digestive resistance. GSDME facilitates the tumour cells to express mucin 1 and mucin 13, which form a barrier to prevent chymotrypsin-mediated destruction. Inoculation of GSDME-/- PDAC cells results in subcutaneous but not orthotopic tumour formation in mice. Inhibition or knockout of mucin 1 or mucin 13 abrogates orthotopic PDAC growth in NOD-SCID mice. Mechanistically, GSDME interacts with and transports YBX1 into the nucleus where YBX1 directly promotes mucin expression. This GSDME-YBX1-mucin axis is also confirmed in patients with PDAC. These findings uncover a unique survival mechanism of PDAC cells in pancreatic microenvironments.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Proteínas Citotóxicas Formadoras de Poros , Adenocarcinoma/genética , Animais , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mucina-1 , Mucinas , Neoplasias Pancreáticas/patologia , Proteínas Citotóxicas Formadoras de Poros/fisiologia , Microambiente Tumoral , Proteína 1 de Ligação a Y-Box
20.
Cell Mol Immunol ; 19(2): 210-221, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34983944

RESUMO

Exploring the cross-talk between the immune system and advanced biomaterials to treat SARS-CoV-2 infection is a promising strategy. Here, we show that ACE2-overexpressing A549 cell-derived microparticles (AO-MPs) are a potential therapeutic agent against SARS-CoV-2 infection. Intranasally administered AO-MPs dexterously navigate the anatomical and biological features of the lungs to enter the alveoli and are taken up by alveolar macrophages (AMs). Then, AO-MPs increase the endosomal pH but decrease the lysosomal pH in AMs, thus escorting bound SARS-CoV-2 from phago-endosomes to lysosomes for degradation. This pH regulation is attributable to oxidized cholesterol, which is enriched in AO-MPs and translocated to endosomal membranes, thus interfering with proton pumps and impairing endosomal acidification. In addition to promoting viral degradation, AO-MPs also inhibit the proinflammatory phenotype of AMs, leading to increased treatment efficacy in a SARS-CoV-2-infected mouse model without side effects. These findings highlight the potential use of AO-MPs to treat SARS-CoV-2-infected patients and showcase the feasibility of MP therapies for combatting emerging respiratory viruses in the future.


Assuntos
Enzima de Conversão de Angiotensina 2/administração & dosagem , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/metabolismo , COVID-19/terapia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Micropartículas Derivadas de Células/metabolismo , Colesterol/metabolismo , Endossomos/química , Macrófagos Alveolares/metabolismo , SARS-CoV-2/metabolismo , Células A549 , Enzima de Conversão de Angiotensina 2/genética , Animais , COVID-19/virologia , Chlorocebus aethiops , Modelos Animais de Doenças , Feminino , Humanos , Concentração de Íons de Hidrogênio , Lisossomos/química , Camundongos , Camundongos Endogâmicos ICR , Camundongos Transgênicos , Oxirredução , Células RAW 264.7 , Resultado do Tratamento , Células Vero
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