Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 58
Filtrar
1.
Molecules ; 28(3)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36770650

RESUMO

Photocatalytic oxidation is considered one of the most effective ways to remove formaldehyde from indoor air. However, the use of powder photocatalysts is limited by their low adsorption capacity and strong aggregation tendency. Hence, there is a need for a composite material with good cycling stability and high degradation efficiency. In the present study, a unique wood-based composite is produced by arranging Cu-TiO2 nanoparticles on porous structured wood. The porous structure of wood can adsorb formaldehyde, and the abundant functional groups on the surface can act as a reaction platform for anchoring the Cu-TiO2 nanoparticles. Cu doping facilitates electron interaction between TiO2 and Cu, promotes the transfer of charge carriers, lowers the electron-hole recombination rate, and improves the photocatalytic degradation efficiency of formaldehyde. The photocatalytic efficiency of the wood-based composites was highest (85.59%) when the n(Cu)/n(Ti) ratio was 7%. After nine cycles, the wood composites still had a high degradation rate, indicating good recyclability. Overall, this wood composite is an eco-friendly and promising material for indoor air filtration.

2.
Molecules ; 29(1)2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38202816

RESUMO

Heterostructured materials show great potential to enhance the specific capacity, rate performance and cycling lifespan of lithium-ion batteries owing to their unique interfaces, robust architectures, and synergistic effects. Herein, a polypyrrole (PPy)-coated nanotube-like Mo3S4/CoMo2S4 heterostructure is prepared by the hydrothermal and subsequent in situ polymerization methods. The well-designed nanotube-like structure is beneficial to relieve the serious volume changes and facilitate the infiltration of electrolytes during the charge/discharge process. The Mo3S4/CoMo2S4 heterostructure could effectively enhance the electrical conductivity and Li+ transport kinetics owing to the refined energy band structure and the internal electric field at the heterostructure interface. Moreover, the conductive PPy-coated layer could inhibit the obvious volume expansion like a firm armor and further avoid the pulverization of the active material and aggregation of generated products. Benefiting from the synergistic effects of the well-designed heterostructure and PPy-coated nanotube-like architecture, the prepared Mo3S4/CoMo2S4 heterostructure delivers high reversible capacity (1251.3 mAh g-1 at 300 mA g-1), superior rate performance (340.3 mAh g-1 at 5.0 A g-1) and excellent cycling lifespan (744.1 mAh g-1 after 600 cycles at a current density of 2.0 A g-1). Such a design concept provides a promising strategy towards heterostructure materials to enhance their lithium storage performances and boost their practical applications.

3.
Data Knowl Eng ; 146: 102193, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37251597

RESUMO

The outbreak of the COVID-19 epidemic has had a huge impact on a global scale and its impact has covered almost all human industries. The Chinese government enacted a series of policies to restrict the transportation industry in order to slow the spread of the COVID-19 virus in early 2020. With the gradual control of the COVID-19 epidemic and the reduction of confirmed cases, the Chinese transportation industry has gradually recovered. The traffic revitalization index is the main indicator for evaluating the degree of recovery of the urban transportation industry after being affected by the COVID-19 epidemic. The prediction research of traffic revitalization index can help the relevant government departments to know the state of urban traffic from the macro level and formulate relevant policies. Therefore, this study proposes a deep spatial-temporal prediction model based on tree structure for the traffic revitalization index. The model mainly includes spatial convolution module, temporal convolution module and matrix data fusion module. The spatial convolution module builds a tree convolution process based on the tree structure that can contain directional features and hierarchical features of urban nodes. The temporal convolution module constructs a deep network for capturing temporal dependent features of the data in the multi-layer residual structure. The matrix data fusion module can perform multi-scale fusion of COVID-19 epidemic data and traffic revitalization index data to further improve the prediction effect of the model. In this study, experimental comparisons between our model and multiple baseline models are conducted on real datasets. The experimental results show that our model has an average improvement of 21%, 18%, and 23% in MAE, RMSE and MAPE indicators, respectively.

4.
Molecules ; 26(3)2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33514014

RESUMO

Vascular bundles play important roles in transporting nutrients, growth signals, amino acids, and proteins between aerial and underground tissues. In order to understand these sophisticated processes, a comprehensive analysis of the roles of the components located in the vascular tissues is required. A great deal of data has been obtained from proteomic analyses of vascular tissues in plants, which mainly aim to identify the proteins moving through the vascular tissues. Here, different aspects of the phloem and xylem proteins are reviewed, including their collection methods, and their main biological roles in growth, and biotic and abiotic stress responses. The study of vascular proteomics shows great potential to contribute to our understanding of the biological mechanisms related to development and defense in plants.


Assuntos
Proteínas Sanguíneas/metabolismo , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Proteoma/metabolismo , Floema/metabolismo , Proteômica/métodos , Estresse Fisiológico/fisiologia , Xilema/metabolismo
5.
Data Knowl Eng ; 135: 101912, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34602688

RESUMO

The research of traffic revitalization index can provide support for the formulation and adjustment of policies related to urban management, epidemic prevention and resumption of work and production. This paper proposes a deep model for the prediction of urban Traffic Revitalization Index (DeepTRI). The DeepTRI builds model for the data of COVID-19 epidemic and traffic revitalization index for major cities in China. The location information of 29 cities forms the topological structure of graph. The Spatial Convolution Layer proposed in this paper captures the spatial correlation features of the graph structure. The special Graph Data Fusion module distributes and fuses the two kinds of data according to different proportions to increase the trend of spatial correlation of the data. In order to reduce the complexity of the computational process, the Temporal Convolution Layer replaces the gated recursive mechanism of the traditional recurrent neural network with a multi-level residual structure. It uses the dilated convolution whose dilation factor changes according to convex function to control the dynamic change of the receptive field and uses causal convolution to fully mine the historical information of the data to optimize the ability of long-term prediction. The comparative experiments among DeepTRI and three baselines (traditional recurrent neural network, ordinary spatial-temporal model and graph spatial-temporal model) show the advantages of DeepTRI in the evaluation index and resolving two under-fitting problems (under-fitting of edge values and under-fitting of local peaks).

6.
Comput Electr Eng ; 93: 107235, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34642506

RESUMO

Predicting the population density of key areas of the city is crucial. It helps reduce the spread risk of Covid-19 and predict individuals' travel needs. Although current researches focus on using the method of clustering to predict the population density, there is almost no discussion about using spatial-temporal models to predict the population density of key areas in a city without using actual regional images. We abstract 997 key areas and their regional connections into a graph structure and propose a model called Word Embedded Spatial-temporal Graph Convolutional Network (WE-STGCN). WE-STGCN is mainly composed of the Spatial Convolution Layer, the Temporal Convolution Layer, and the Feature Component. Based on the data set provided by the DataFountain platform, we evaluate the model and compare it with some typical models. Experimental results show that WE-STGCN has 53.97% improved to baselines on average and can commendably predicting the population density of key areas.

7.
Angew Chem Int Ed Engl ; 60(47): 25013-25019, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34523206

RESUMO

We present a coral-like FeP composite with FeP nanoparticles anchored and dispersed on a nitrogen-doped 3D carbon framework (FeP@NC). Due to the highly continuous N-doped carbon framework and a spring-buffering graphitized carbon layer around the FeP nanoparticle, a sodium-ion battery with the FeP@NC composite exhibits an ultra-stable cycling performance at 10 A g-1 with a capacity retention of 82.0 % in 10 000 cycles. Also, particle refinement leads to a capacity increase during cycling. The FeP nanoparticles go through a refining-recombination process during the first cycle and present a global refining trend after dozens of cycles, which results in a gradually increase in graphitization degree and interface magnetization, and further provides more active sites for Na+ storage and contributes to a rising capacity with cycling. The capacity ascending phenomenon can also extend to lithium-ion batteries.

8.
Cytokine ; 130: 155047, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32200264

RESUMO

Osteoarthritis (OA) is a highly prevalent joint disorder that is tightly correlated with age. As the body ages, cell replication and function decline until homeostasis can no longer be maintained. This process involves cellular senescence as well as replicative senescence. Telomere length, cell cycle arrest, expression of p16 and p53, and the release of senescence-associated ß-galactosidase (SA-ß-Gal) are all markers of cell senescence. In OA joints, chondrocytes undergo cellular senescence prematurely, thereby ceasing to synthesize and maintain cartilage tissue. Upregulation of proinflammatory cytokines, such as tumor necrosis factor-α (TNF-α), and oxidative stress induced by overproduction of reactive oxygen species (ROS) are key events in the pathogenesis of OA. In the present study, we investigated the effects of pinitol, a naturally occurring compound, on the effects of TNF-α on chondrocyte senescence and cell cycle arrest. We found that pinitol has a favorable safety profile in terms of cell viability. Pinitol significantly inhibited cellular senescence and cell cycle arrest in the G0/G1 phase induced by TNF-α. We also found that pinitol could inhibit TNF-α-induced increased telomerase activity and expression of p16 and p53. Importantly, we found that the effects of pinitol may be mediated through rescue of Nrf2 signaling, which is recognized as a key protective factor in OA. This finding was verified through a Nrf2 silencing experiment using Nrf2 siRNA. Together, our findings reveal the potential of pinitol as a safe therapeutic option for the prevention of OA-associated chondrocyte senescence and oxidative stress.

9.
Int J Mol Sci ; 20(10)2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31137512

RESUMO

Intensive investigations have been conducted on the effect of sole drought or salinity stress on the growth of plants. However, there is relatively little knowledge on how plants, particularly woody species, respond to a combination of these two stresses although these stresses can simultaneously occur in the field. In this study, mulberry, an economically important resource for traditional medicine, and the sole food of domesticated silkworms was subjected to a combination of salt and drought stress and analyzed by physiological methods and TMT-based proteomics. Stressed mulberry exhibited significant alteration in physiological parameters, including root/shoot ratio, chlorophyll fluorescence, total carbon, and ion reallocation. A total of 577 and 270 differentially expressed proteins (DEPs) were identified from the stressed leaves and roots, respectively. Through KEGG analysis, these DEPs were assigned to multiple pathways, including carbon metabolism, photosynthesis, redox, secondary metabolism, and hormone metabolism. Among these pathways, the sucrose related metabolic pathway was distinctly enriched in both stressed leaves and roots, indicating an important contribution in mulberry under stress condition. The results provide a comprehensive understanding of the adaptive mechanism of mulberry in response to salt and drought stress, which will facilitate further studies on innovations in terms of crop performance.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Morus/genética , Proteínas de Plantas/genética , Proteoma/genética , Estresse Salino , Morus/metabolismo , Morus/fisiologia , Proteínas de Plantas/metabolismo , Proteoma/metabolismo
10.
Pulm Pharmacol Ther ; 42: 33-42, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28062322

RESUMO

BACKGROUND: MicroRNAs are small yet versatile gene tuners that regulate a variety of cellular processes, including cell growth and proliferation. Here we report that miR-23b inhibited airway smooth muscle cells (ASMCs) proliferation through directly targeting of Smad3. METHODS: We obtained ASMCs by laser capture microdissection of normal and asthmatic mice lung tissues. Mice ASMCs were cultured and induced by TGF-ß1. The implication between TGF-ß1 and miR-23b in ASMCs were detected by RT-PCR. The effects of miR-23b on ASMCs proliferation and apoptosis were assessed by transient transfection of miR-23b mimics and inhibitor. The expression of Smad3 in ASMCs were detected by RT-PCR and Western blotting analysis. Dual-Luciferase Reporter Assay System will be applied to identify whether Smad3 is a target gene of miR-23b. RESULTS: TGF-ß1 and miR-23b mRNA expression of in-situ bronchial ASMCs collected by laser capture microdissection were increased in asthmatic mice compared to non-asthma controls. This is accompanied by an increase in miR-23b mRNA expression in TGF-ß1 induced ASMCs. miR-23b up-regulation significantly inhibited TGF-ß1-induced ASMCs proliferation and promoted apoptosis. MiR-23b negatively regulates the expression of Smad3 in ASMCs. Dual-Luciferase Reporter Assay System demonstrated that Smad3 was a direct target of miR-23b. CONCLUSIONS: MiR-23b may function as an inhibitor of asthma airway remodeling by suppressing ASMCs proliferation via direct targeting of Smad3.


Assuntos
Proliferação de Células/genética , MicroRNAs/genética , Proteína Smad3/genética , Fator de Crescimento Transformador beta1/metabolismo , Remodelação das Vias Aéreas/genética , Animais , Apoptose/genética , Asma/genética , Asma/fisiopatologia , Western Blotting , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Miócitos de Músculo Liso/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
11.
J Asthma ; 54(5): 467-475, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27905842

RESUMO

OBJECTIVE: This study aimed to elucidate the role of Transforming growth factor (TGF)-ß1 signaling in the proliferation of airway smooth muscle cells (ASMCs). BACKGROUND: TGF-ß1 is an important cytokine in airway remodeling in asthma. However, results of studies focusing on the effect of TGFß1 on proliferation of ASMCs are controversial. METHODS: An allergic model that mimics airway remodeling in chronic asthma was established and primary ASMCs were cultured. Cell proliferation was detected by viable cell counting and Cell Counting Kit (CCK)-8 analysis. Expression and phosphorylation of Smad3, type 1 TGFß receptor (TGFßRI), type 2 TGFß receptor (TGFßRII), extracellular signal-regulated kinase (ERK)-1/2, p38 mitogen-activated protein kinase (MAPK), C-Jun N-terminal kinase (JNK) and AKT were detected by western blot. siRNAs were used to knock down Smad3 and TGFßRII. RESULTS: Smad3 and TGFßRII were up-regulated in primary ASMCs isolated from ovalbumin (OVA)-sensitized mice as compared with ASMCs isolated from unsensitized control mice, which persisted for at least four passages. TGFß1 stimulated proliferation of ASMCs isolated from OVA-sensitized mice, which was inhibited by specific siRNA targeting Smad3 or TGFßRII. However ASMCs from control mice showed no proliferative response to TGFß1. TGFß1-induced proliferation of ASMCs from OVA-sensitized mice was markedly attenuated by PD-98059, a specific ERK1/2 inhibitor. TGFß1 induced ERK1/2 phosphorylation within 15 minute, which was partially blocked by specific inhibitor of Smad3 (SIS3). CONCLUSIONS: ASMCs isolated from OVA-sensitized mice showed hyper-proliferation upon TGFß1 stimulation. This might have been associated with up-regulated Smad3 and TGFßRII and mediated by ERK1/2 downstream to Smad3.


Assuntos
Remodelação das Vias Aéreas/fisiologia , Asma/fisiopatologia , Miócitos de Músculo Liso/patologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/farmacologia , RNA Interferente Pequeno/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Proteína Smad3/biossíntese , Regulação para Cima
12.
Exp Cell Res ; 331(2): 362-8, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25447441

RESUMO

BACKGROUND: We have reported that triptolide can inhibit airway remodeling in a murine model of asthma via TGF-ß1/Smad signaling. In the present study, we aimed to investigate the effect of triptolide on airway smooth muscle cells (ASMCs) proliferation and the possible mechanism. METHODS: Rat airway smooth muscle cells were cultured and made synchronized, then pretreated with different concentration of triptolide before stimulated by TGF-ß1. Cell proliferation was evaluated by MTT assay. Flow cytometry was used to study the influence of triptolide on cell cycle and apoptosis. Signal proteins (Smad2, Smad3 and Smad7) were detected by western blotting analysis. RESULTS: Triptolide significantly inhibited TGF-ß1-induced ASMC proliferation (P<0.05). The cell cycle was blocked at G1/S-interphase by triptolide dose dependently. No pro-apoptotic effects were detected under the concentration of triptolide we used. Western blotting analysis showed TGF-ß1 induced Smad2 and Smad3 phosphorylation was inhibited by triptolide pretreatment, and the level of Smad7 was increased by triptolide pretreatment. CONCLUSIONS: Triptolide may function as an inhibitor of asthma airway remodeling by suppressing ASMCs proliferation via negative regulation of Smad signaling pathway.


Assuntos
Remodelação das Vias Aéreas/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/farmacologia , Asma/patologia , Diterpenos/farmacologia , Imunossupressores/farmacologia , Fenantrenos/farmacologia , Fator de Crescimento Transformador beta1/farmacologia , Animais , Apoptose/efeitos dos fármacos , Asma/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Compostos de Epóxi/farmacologia , Masculino , Miócitos de Músculo Liso/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Proteína Smad7/biossíntese , Proteína Smad7/metabolismo
13.
J Clin Lab Anal ; 30(5): 581-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26666630

RESUMO

BACKGROUND: The human epididymis protein 4 (HE4) may have high specificity in the detection of malignant diseases, making the development of an immunoassay for HE4 essential. METHODS: In our study, a fusion gene was constructed encoded with the HE4 protein. This protein was then produced in the bacterial cells (Escherichia coli) and used to immunize mice in order to eventually generate hybridomas specific to HE4. The hybridoma supernatants were then screened, and four positive anti-HE4 cell lines were selected. These cell lines produce monoclonal antibodies against HE4 epitopes, as demonstrated in the Western blot as well as by direct enzyme-linked immunosorbent assay (ELISA). Using the developed antibodies, we successfully identified several good antibody pairs from the hybridomas, which allowed for the development of a sandwich ELISA to measure HE4 levels. By using the HE4 ELISA, we measured HE4 levels of 60 clinical human serum samples. RESULTS: Compared with the Food and Drug Administration (FDA) approved kit (Roche), our results showed a strong positive correlation to those of the FDA-approved kit. CONCLUSIONS: In summary, highly sensitive antibody pairs were screened against HE4, and a sandwich ELISA was developed as an accurate analytical tool for the detection of HE4 in human serum, which could be especially valuable for diagnosing ovarian carcinomas.


Assuntos
Anticorpos Monoclonais/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Neoplasias Ovarianas/sangue , Proteínas/imunologia , Proteínas/metabolismo , Adolescente , Adulto , Idoso , Animais , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos , Adulto Jovem
14.
Molecules ; 21(7)2016 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-27447597

RESUMO

Protocatechualdehyde (PCA) extracted from Phellinus gilvus exhibits anti-cancer activity in human colorectal carcinoma cells (HT-29). However, the underlying mechanisms remain poorly understood. We performed an in vitro study involving MTT, flow cytometry, RT-PCR, and western blot analyses to investigate the effects of PCA treatment on cell proliferation, cell cycle distribution, apoptosis, and expression of several cell cycle-related genes in HT-29 cells. The treatment enhanced S-phase cell cycle and apoptosis in HT-29 cells in a dose-dependent manner. Western blot results showed that PCA treatment decreased the expression levels of cyclin A, cyclin D1, and p27(KIP1) but increased those of cyclin-dependent kinase 2 (CDK2) in HT-29 cells. Furthermore, the expression levels of B-cell lymphoma/leukemia-2 (Bcl-2) and B-cell lymphoma/leukemia-xL (Bcl-xL) were down-regulated, whereas the levels of BH3-interacting domain death agonist (Bid), Bcl-2 homologous antagonist/killer (Bak), and cytosolic cytochrome c were significantly upregulated. Thus, the enzymes caspases-9, -3, -8, and -6 were found to be activated in HT-29 cells with PCA treatment. These results indicate that PCA-induced S-phase cell cycle arrest and apoptosis involve p27(KIP1)-mediated activation of the cyclin-A/D1-Cdk2 signaling pathway and the mitochondrial apoptotic pathway.


Assuntos
Apoptose/efeitos dos fármacos , Benzaldeídos/farmacologia , Catecóis/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Benzaldeídos/química , Catecóis/química , Proliferação de Células/efeitos dos fármacos , Ciclina A1/metabolismo , Ciclina D1/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Células HT29 , Humanos
15.
Biochim Biophys Acta ; 1845(2): 182-201, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24440852

RESUMO

Until recently, the intrinsically high level of cross-talk between immune cells, the complexity of immune cell development, and the pleiotropic nature of cytokine signaling have hampered progress in understanding the mechanisms of immunosuppression by which tumor cells circumvent native and adaptive immune responses. One technology that has helped to shed light on this complex signaling network is the cytokine antibody array, which facilitates simultaneous screening of dozens to hundreds of secreted signal proteins in complex biological samples. The combined applications of traditional methods of molecular and cell biology with the high-content, high-throughput screening capabilities of cytokine antibody arrays and other multiplexed immunoassays have revealed a complex mechanism that involves multiple cytokine signals contributed not just by tumor cells but by stromal cells and a wide spectrum of immune cell types. This review will summarize the interactions among cancerous and immune cell types, as well as the key cytokine signals that are required for tumors to survive immunoediting in a dormant state or to grow and spread by escaping it. Additionally, it will present examples of how probing secreted cell-cell signal networks in the tumor microenvironment (TME) with cytokine screens have contributed to our current understanding of these processes and discuss the implications of this understanding to antitumor therapies.


Assuntos
Citocinas/metabolismo , Sistema Imunitário/metabolismo , Terapia de Imunossupressão , Monitorização Imunológica , Neoplasias/imunologia , Comunicação Celular/imunologia , Citocinas/genética , Humanos , Sistema Imunitário/citologia , Neoplasias/genética , Neoplasias/patologia , Transdução de Sinais/imunologia , Células Estromais/citologia , Células Estromais/imunologia , Microambiente Tumoral/imunologia
16.
J Exp Bot ; 66(19): 5809-20, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26085677

RESUMO

The caseinolytic peptidase (Clp) core proteins are essential for plant growth and development, especially for chloroplast function. Antisense or overexpression of ClpP4, which is one of the Clp core subunits, causes chlorotic phenotypes in Arabidopsis. An E3 ligase gene, AtCHIP, has previously been found to ubiquitylate ClpP4 in vitro. ClpP4 antisense and overexpressing plants that also overexpressed AtCHIP were constructed to explore the effect of AtCHIP on ClpP4. Overexpression of AtCHIP was found to rescue the chlorotic phenotypes of both ClpP4 antisense and overexpressing plants. The unbalanced levels of Clp core proteins in ClpP4 antisense and overexpressing plants with overexpression of AtCHIP were similar to wild-type levels, suggesting that AtCHIP regulates Clp core proteins. The results also show that AtCHIP can interact with ClpP3 and ClpP5 in yeast and ubiquitylate ClpP3 and ClpP5 in vitro. This suggests that AtCHIP is directly related to ClpP3 and ClpP5. Given these results, the inference is that through selective degradation of Clp subunits, AtCHIP could positively regulate homeostasis of Clp proteolytic subunits and maximize the production of functional chloroplasts. Similar results were obtained from transgenic tobacco plants, suggesting that regulation of the Clp protease by AtCHIP is conserved.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Endopeptidase Clp/genética , Homeostase , Ubiquitina-Proteína Ligases/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Endopeptidase Clp/metabolismo , Proteólise , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
17.
Immunology ; 2014 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-25267491

RESUMO

BACKGROUND: Airway remodeling contributes to increased mortality in asthma. We have reported that triptolide can inhibit airway remodeling in a mouse asthma model. In this study, we aimed to investigate the effect of triptolide on airway smooth muscle cells (ASMCs) proliferation, migration and the possible mechanism. METHODS: Rat airway smooth muscle cells were cultured and made synchronized, then pretreated with different concentrations of triptolide before stimulated by TGF-ß1. Cell proliferation was evaluated by cell counting and MTT assay. Flow cytometry was used to study the influence of triptolide on cell cycle. Migration was measured by Transwell analysis. Signal proteins (NF-κB p65 and ERK1/2) were detected by western blotting analysis. LDH releasing test and flow cytometry analysis of apoptosis were also performed to explore the potential cytotoxic or pro-apoptotic effects of triptolide. RESULTS: Triptolide significantly inhibited TGF-ß1 induced ASMC proliferation and migration (p<0.05). The cell cycle was blocked at G1/S-interphase by triptolide dose dependently. Western blotting analysis showed TGF-ß1 induced NF-κB p65 phosphorylation was inhibited by triptolide pretreatment, but ERK1/2 was not affected. No cytotoxic or pro-apoptotic effects were detected under the concentration of triptolide we used. CONCLUSIONS: Triptolide may function as an inhibitor of asthma airway remodeling by suppressing ASMCs proliferation and migration through inactivation of NF-κB pathway. This article is protected by copyright. All rights reserved.

18.
Sci Rep ; 14(1): 15207, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956294

RESUMO

The creep characteristics and potential deformation patterns of gangue backfill material are crucial in backfill mining operations. This study utilizes crushed gangue from the Gangue Yard in Fuxin City as the research material. An in-house designed, large-scale, triaxial gangue compaction test system was used. Triaxial compaction creep tests were conducted on gangue materials with varying particle size distributions. Analysis was performed based on different particle sizes, stresses, and confinement pressures. The study investigates the creep characteristics of the gangue under different conditions and explores the underlying causes. It reveals the relationship between the creep deformation of gangue materials and the passage of time. Mathematical methods are applied to develop a triaxial compaction creep power law model for gangue backfill materials. Finally, the creep results are fitted using an empirical formula approach.

19.
Anim Nutr ; 16: 34-44, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38131029

RESUMO

Skatole, a strong fecal odor substance, is generated through microbial degradation of tryptophan in the animal hindgut. It easily accumulates in adipose tissue and affects meat quality. In this study, the effect of mulberry leaf supplementation on skatole in finishing pigs was studied. In a 35-day trial, 20 finishing pigs (barrows and gilts) were fed with a basal diet or basal diet with 6% mulberry leaves. Growth performance of the pigs (n = 10) was automatically recorded by a performance-testing feeder system and 8 pigs in each treatment were slaughtered and sampled for the remaining tests. Skatole and short-chain fatty acids were detected using HPLC and gas chromatography, respectively. Fecal microbiota were analyzed using 16S rRNA gene sequencing. The metabolomics analysis of feces and serum was performed with UHPLC-MS/MS. The major cytochrome P450 (CYP) enzymes that catalyze skatole degradation in the liver were tested by using RT-PCR and Western blot. Effects of major bioactive compounds in mulberry leaves on the CYP genes were verified in the hepatic cell line HepG2 in an in vitro test (n = 3). In finishing pigs, mulberry leaf supplementation had no significant effect on the average daily gain, average daily feed intake, and feed conversion ratio (P > 0.05), but reduced skatole levels in feces, serum, and backfat (P < 0.05), and increased acetic acid levels in feces (P = 0.027). Mulberry leaf supplementation decreased the relative abundance of the skatole-producing bacteria Megasphaera and Olsenella (P < 0.05). Indole-3-acetic acid, the intermediate that is essential for skatole production, was significantly reduced in feces by mulberry leaf supplementation (P < 0.05) and was positively correlated with skatole content in feces (P = 0.004). In pigs treated with mulberry leaves, liver CYP1A1 expression was increased (P < 0.05) and was negatively correlated with skatole content in backfat (P = 0.045). The in vitro test demonstrated that mulberry leaf polyphenols and polysaccharides could directly stimulate CYP1A1 expression in hepatic cells. These findings suggest that mulberry leaf supplementation reduces skatole production and deposition in finishing pigs by regulating the gut microbiota and promoting skatole degradation in liver.

20.
J Colloid Interface Sci ; 666: 540-546, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38613976

RESUMO

Na3V2(PO4)3 is considered as one of the most promising cathodes for sodium ion batteries owing to its fast Na+ diffusion, good structural stability and high working potential. However, its practical application is limited by its low intrinsic electronic conductivity. Herein, a carbon coated Cu2+-doped Na3V2(PO4)3 cathode was prepared. The carbon coating not only improve its apparent conductivity, but also inhibit crystal growth and prevent agglomeration of particles. Moreover, Cu2+ doping contributes to an enhanced intrinsic conductivity and decreased Na+ diffusion energy barrier, remarkably boosting its charge transfer kinetics. Based on the structure characterizations, electrochemical performances tests, charge transfer kinetics analyses and theoretical calculations, it's proved that such an elaborate design ensures the excellent rate performances (116.9 mA h g-1 at 0.1C; 92.6 mA h g-1 at 10C) and distinguished cycling lifespan (95.8 % retention after 300 cycles at 1C; 84.8 % retention after 3300 cycles at 10C). Besides, a two-phase reaction mechanism is also confirmed via in-situ XRD. This research is expected to promote the development of Na3V2(PO4)3-based sodium ion batteries with high energy/power density and excellent cycling lifespan.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA