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1.
Front Immunol ; 15: 1338744, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38352879

RESUMO

Sepsis is a multisystem disease characterized by dysregulation of the host immune response to infection. Immune response kinetics play a crucial role in the pathogenesis and progression of sepsis. Macrophages, which are known for their heterogeneity and plasticity, actively participate in the immune response during sepsis. These cells are influenced by the ever-changing immune microenvironment and exhibit two-sided immune regulation. Recently, the immunomodulatory function of mesenchymal stem cells (MSCs) in sepsis has garnered significant attention. The immune microenvironment can profoundly impact MSCs, prompting them to exhibit dual immunomodulatory functions akin to a double-edged sword. This discovery holds great importance for understanding sepsis progression and devising effective treatment strategies. Importantly, there is a close interrelationship between macrophages and MSCs, characterized by the fact that during sepsis, these two cell types interact and cooperate to regulate inflammatory processes. This review summarizes the plasticity of macrophages and MSCs within the immune microenvironment during sepsis, as well as the intricate crosstalk between them. This remains an important concern for the future use of these cells for immunomodulatory treatments in the clinic.


Assuntos
Células-Tronco Mesenquimais , Sepse , Humanos , Macrófagos , Imunomodulação , Imunidade , Células-Tronco Mesenquimais/metabolismo , Sepse/metabolismo
2.
Polymers (Basel) ; 16(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38201818

RESUMO

To effectively utilize waste mask materials in road engineering and minimize resource waste, the melt-blown fabric (MBF) of waste masks was utilized to modify the virgin bitumen. The preparation process of MBF-modified bitumen was investigated, and the physical and rheological properties of bitumen were measured. Subsequently, the blending mechanism during preparation and the dispersion morphology of the modifier were explored. Finally, the pavement performance of the mixture was investigated, and a radar chart analysis was performed to quantitatively assess the effects of MBF modification. Results suggested that the recommended preparation process of shear time, shear rate, and shear temperature was 170 °C, 4000 r/min, and 15 min, respectively. MBF enhanced the high-temperature stability of the binder and weakened the temperature susceptibility. The modification was primarily a physical process. No network structure and agglomeration formed in the bitumen after modification. The addition of MBF significantly improved the resistance of the asphalt mixture to a high-temperature deformation and water damage but harmed its low-temperature crack resistance. The comprehensive assessment results of 0% (f1), 1% (f2), 3% (f3), and 5% (f4) MBF to improve the properties of the mixture were in the following order: f3>f4>f2>f1, where the impact of 3% MBF was the most significant, followed by 5% and 1% MBF.

3.
Materials (Basel) ; 16(19)2023 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-37834522

RESUMO

In order to study the self-healing performance of macroscopic fractures of asphalt mixtures, semicircular bending (SCB) tests were used to test 90# base asphalt mixtures, SBS (Styrene-Butadiene-Styrene) modified asphalt mixtures, and SBS + CR (Chloroprene Rubber) composite modified asphalt mixtures. The F-H-F (the asphalt mixture specimen was fatigued for a certain number of times, then healed under certain conditions, and then fatigued until destroyed) test was carried out, and the fatigue life recovery rate of the fatigue test before and after healing was defined as the healing index (HI). The gray correlation analysis method was used to judge the influence degree of influencing factors on fatigue-healing according to the correlation index. The results show the type of asphalt has the most significant influence on the healing ability of the asphalt mixture. In the case of complete healing, the fatigue-healing performance of the SBS + CR composite modified asphalt mixture was the best, followed by the SBS-modified asphalt mixture, and 90# base asphalt. When the healing temperature is close to the softening point of asphalt, the healing performance of 90# base asphalt is better when the healing temperature is low. When the healing time is longer, the healing performance is better, and there is an optimal healing time. The healing index decreased with the increase in the degree of damage. When the degree of damage is too large, the asphalt mixture will be difficult to heal.

4.
Materials (Basel) ; 16(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37834600

RESUMO

In order to investigate the influence of recycling agent composition on the recycling effect of aged asphalt in the cold recycling process, the design and optimization of cold recycling agent composition were performed through the central composite design-response surface method combined with the dynamic shear rheometer (DSR) test and the bending beam rheometer (BBR) test. The molecular weight distribution and component changes in aged asphalt before and after the addition of a cold recycling agent were also analyzed by gel permeation chromatography (GPC) and hydrogen-flame ionization test. The results showed that the permeable cold recycling agent has a recycling effect on the aged asphalt, but its effectiveness is greatly affected by recycling agent composition. The best recycling effect was achieved when the ratio of aromatic oil and penetrant in the cold recycling agent was 61.2:38.8, respectively. In terms of the recycling agent and aromatic functional groups in the aromatic oil, the aromatics in the recycling agent are derived from the aromatic oils, and the penetrant is only fused and permeated with the aromatic oils. After the admixture of the cold recycling agent, the penetrant in the recycling agent allows the aromatic oil to enter the aged asphalt at room temperature. The light components volatilized by aging are replenished, allowing the aged asphalt to recover some of its properties.

5.
Polymers (Basel) ; 15(12)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37376277

RESUMO

Semi-flexible pavement material (SFPM) combines the advantages and avoids the disadvantages of asphalt concrete flexible pavement and cement concrete rigid pavement. However, due to the problem of interfacial strength of composite materials, SFPM is prone to cracking diseases, which limits the further application of SFPM. Hence, it is necessary to optimize the composition design of SFPM and improve its road performance. In this study, the effects of cationic emulsified asphalt, silane coupling agent and styrene-butadiene latex on the improvement of SFPM performance were compared and analyzed. The influence of modifier dosage and preparation parameters on the road performance of SFPM was investigated by an orthogonal experimental design combined with principal component analysis (PCA). The best modifier and the corresponding preparation process were selected. On this basis, the mechanism of SFPM road performance improvement was further analyzed by scanning electron microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) spectral analysis. The results show that adding modifiers can significantly enhance the road performance of SFPM. Compared to silane coupling agents and styrene-butadiene latex, cationic emulsified asphalt changes the internal structure of cement-based grouting material and increases the interfacial modulus of SFPM by 242%, allowing cationic emulsified asphalt-SFPM (C-SFPM) to exhibit better road performance. According to the results of the principal component analysis, C-SFPM has the best overall performance compared to other SFPMs. Therefore, cationic emulsified asphalt is the most effective modifier for SFPM. The optimal amount of cationic emulsified asphalt is 5%, and the best preparation process involves vibration at a frequency of 60 Hz for 10 min and 28 days of maintenance. The study provides a method and basis for improving the road performance of SFPM and a reference for designing the material composition of SFPM mixes.

6.
Heliyon ; 8(11): e11518, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36406694

RESUMO

Phosphogypsum (PG) is a major hazardous by-product of the phosphate industry. The whole world is facing the challenge of increasing stockpiles of PG, which significantly affect safety and the environment. Recycling this material may be an environmentally friendly and safe solution to this challenge. In this paper, we searched the Web of Science database for 2369 articles from 1975 to 2022 using "phosphogypsum" as the keyword. Using the VOSviewer as the literature visualisation tool, density visualisation was performed with keywords as the analysis units, and it was found that the researchers focused mainly on PG applications in construction and radionuclides. Over the years, different routes to PG valorisation have been developed in the agricultural, construction, environmental and energy sectors, and these topics are described in this review. As infrastructure projects, highway engineering is characterised by a large land area and high resource consumption. Therefore, applying PG to road materials can significantly increase the reuse and consumption of PG and reduce PG stockpiles. We hope that PG can be used for road construction on a large scale in the future. This paper focuses on the latest developments in PG as road materials. The most serious difficulty in using PG as road materials at present is that it contains radionuclides and heavy metal impurities, which can be purified by pretreatment methods. However, how to scale it up requires continuous research.

7.
Polymers (Basel) ; 13(14)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34301115

RESUMO

In this study, the effects of polyvinyl chloride (PVC) and nano silica (NS) as modifiers on the properties of stone matrix asphalt (SMA) were studied. The experiment was performed with five modes: 1% NS was mixed into SMA; 5% PVC was mixed into SMA; and the ratio of NS was changed (1, 2, and 3%) with 5% PVC being mixed into SMA. The properties of modified and unmodified SMA materials were determined and compared by performing the penetration test, softening points test, viscosity measurements, dynamic shear rheometry, and multiple stress creep recovery under aging conditions. Moreover, the properties of the modified SMA were also determined in terms of Marshall stability, water stability, and rutting resistance. The obtained results indicate that the physical properties of SMA materials could be significantly improved by using a combination of PVC and NS as a modifier. Moreover, the SMA mixtures modified with PVC and NS exhibited high Marshall stability, good moisture damage resistance, and rutting resistance. Modified SMA mixtures with 5% PVC and 1% NS exhibited the best quality. This research has opened up a new avenue for the development of effective additives for SMA materials.

8.
Materials (Basel) ; 14(6)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809435

RESUMO

In this research, the feasibility of using nano-montmorillonite (MMT) in asphalt binders was investigated in terms of rheological properties, thermomechanical properties, and chemical structure composition. Different doses of MMT were added to the base asphalt and styrene-butadiene-styrene (SBS) asphalt as test subjects. The effect of nanomaterials on the high-temperature resistance of asphalt binders to permanent deformation was analyzed from dynamic mechanical rheology using the multiple stress creep recovery (MSCR) test. The sessile drop method test based on surface free energy (SFE) theory was employed and thermodynamic parameters such as surface free energy, cohesive work, and adhesion work were calculated to analysis the change in energy of the asphalt binder. In addition, changes in the chemical structure and composition of the asphalt binder were examined by Fourier transform infrared (FTIR) and gel permeation chromatography (GPC) tests. The results showed that MMT can effectively enhance the high-temperature elastic recovery and plastic deformation resistance of the asphalt binder. The intercalation structure produced in the asphalt binder enhanced the overall cohesive power and adhesion to the aggregate. The anchoring effect of the intercalation structure resulted in an increase in the macromolecular weight of the binder was demonstrated, indicating that MMT enhanced the overall intermolecular forces of the binder. In addition, the molecular crystal structure was characterized by characteristic functional groups in the infrared spectra, while demonstrating that no chemical reaction occurs during the modification of the binder by the nanomaterials.

9.
Materials (Basel) ; 13(24)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371403

RESUMO

To improve the thermal-aging stability and rheological performance of styrene-butadiene rubber (SBR)-modified asphalt, phenolic resin (PF) was introduced in the process of preparing SBR-modified asphalt by melt blending. The effect of PF and SBR on the high and low-temperature rheological performance of the asphalt binder before and after aging was evaluated by a temperature and frequency sweep using a dynamic shear rheometer (DSR). Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), and fluorescence microscopy (FM) were used to further investigate the effect of PF and SBR on the thermal stability and morphological characteristics of the asphalt binder. The results showed that the addition of PF can enhance the high-temperature deformation resistance and short-term aging resistance of SBR-modified asphalt. Moreover, PF and SBR form an embedded network structure within the asphalt binder and alleviate the deterioration of the polymer during the aging process. Compared with SBR-modified asphalt, the chemical system of composite-modified asphalt is more stable, and it can remain stable with an aging time of less than 5 h.

10.
Cancer Cell ; 38(1): 97-114.e7, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32470392

RESUMO

Small cell lung cancer (SCLC) is a highly aggressive and lethal neoplasm. To identify candidate tumor suppressors we applied CRISPR/Cas9 gene inactivation screens to a cellular model of early-stage SCLC. Among the top hits was MAX, the obligate heterodimerization partner for MYC family proteins that is mutated in human SCLC. Max deletion increases growth and transformation in cells and dramatically accelerates SCLC progression in an Rb1/Trp53-deleted mouse model. In contrast, deletion of Max abrogates tumorigenesis in MYCL-overexpressing SCLC. Max deletion in SCLC resulted in derepression of metabolic genes involved in serine and one-carbon metabolism. By increasing serine biosynthesis, Max-deleted cells exhibit resistance to serine depletion. Thus, Max loss results in metabolic rewiring and context-specific tumor suppression.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Modelos Animais de Doenças , Neoplasias Pulmonares/genética , Carcinoma de Pequenas Células do Pulmão/genética , Proteínas Supressoras de Tumor/genética , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Células Cultivadas , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Células Hep G2 , Humanos , Células K562 , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/metabolismo , Camundongos Knockout , Camundongos Transgênicos , Carcinoma de Pequenas Células do Pulmão/metabolismo , Proteínas Supressoras de Tumor/metabolismo
11.
Rice (N Y) ; 12(1): 86, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776817

RESUMO

BACKGROUND: Histone modifications play important roles in growth and development of rice (Oryza sativa L.). Lysine butyrylation (Kbu) with a four-carbon chain is a newly-discovered histone acylation modification in rice. MAIN BODY: In this study, we performed chromatin immunoprecipitation sequencing (ChIP-seq) analyses, the result showed that major enrichment of histone Kbu located in genebody regions of rice genome, especially in exons. The enrichment level of Kbu histone modification is positively correlated with gene expression. Furthermore, we compared Kbu with DNase-seq and other histone modifications in rice. We found that 60.06% Kub enriched region co-located with DHSs in intergenic regions. The similar profiles were detected among Kbu and several acetylation modifications such as H3K4ac, H3K9ac, and H3K23ac, indicating that Kbu modification is an active signal of transcription. Genes with both histone Kbu and one other acetylation also had significantly increased expression compared with genes with only one acetylation. Gene Ontology (GO) enrichment analysis revealed that these genes with histone Kbu can regulate multiple metabolic process in different rice varieties. CONCLUSION: Our study showed that the lysine butyrylation modificaiton may promote gene expression as histone acetylation and will provide resources for futher studies on histone Kbu and other epigenetic modifications in plants.

12.
Genes Dev ; 33(17-18): 1252-1264, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31395740

RESUMO

Although MAX is regarded as an obligate dimerization partner for MYC, its function in normal development and neoplasia is poorly defined. We show that B-cell-specific deletion of Max has a modest effect on B-cell development but completely abrogates Eµ-Myc-driven lymphomagenesis. While Max loss affects only a few hundred genes in normal B cells, it leads to the global down-regulation of Myc-activated genes in premalignant Eµ-Myc cells. We show that the balance between MYC-MAX and MNT-MAX interactions in B cells shifts in premalignant B cells toward a MYC-driven transcriptional program. Moreover, we found that MAX loss leads to a significant reduction in MYC protein levels and down-regulation of direct transcriptional targets, including regulators of MYC stability. This phenomenon is also observed in multiple cell lines treated with MYC-MAX dimerization inhibitors. Our work uncovers a layer of Myc autoregulation critical for lymphomagenesis yet partly dispensable for normal development.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica , Linfoma/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Carcinogênese/efeitos dos fármacos , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Deleção de Genes , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Indóis/farmacologia , Cinurenina/genética , Cinurenina/metabolismo , Linfoma/fisiopatologia , Camundongos , Organoides/crescimento & desenvolvimento , Organoides/fisiopatologia , Oximas/farmacologia , Sulfonamidas/farmacologia
13.
Genes Dev ; 29(23): 2475-89, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26584623

RESUMO

Metabolic stress and changes in nutrient levels modulate many aspects of skeletal muscle function during aging and disease. Growth factors and cytokines secreted by skeletal muscle, known as myokines, are important signaling factors, but it is largely unknown whether they modulate muscle growth and differentiation in response to nutrients. Here, we found that changes in glucose levels increase the activity of the glucose-responsive transcription factor MLX (Max-like protein X), which promotes and is necessary for myoblast fusion. MLX promotes myogenesis not via an adjustment of glucose metabolism but rather by inducing the expression of several myokines, including insulin-like growth factor 2 (IGF2), whereas RNAi and dominant-negative MLX reduce IGF2 expression and block myogenesis. This phenotype is rescued by conditioned medium from control muscle cells and by recombinant IGF2, which activates the myogenic kinase Akt. Importantly, MLX-null mice display decreased IGF2 induction and diminished muscle regeneration in response to injury, indicating that the myogenic function of MLX is manifested in vivo. Thus, glucose is a signaling molecule that regulates myogenesis and muscle regeneration via MLX/IGF2/Akt signaling.


Assuntos
Desenvolvimento Muscular/genética , Músculo Esquelético/citologia , Proteínas Nucleares/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Acetilação , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Linhagem Celular , Regulação da Expressão Gênica no Desenvolvimento/genética , Glucose/metabolismo , Histonas/metabolismo , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/fisiologia , Regeneração
14.
Cell Stem Cell ; 3(6): 611-24, 2008 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-19041778

RESUMO

Myc activity is emerging as a key element in acquisition and maintenance of stem cell properties. We have previously shown that c-Myc deficiency results in accumulation of defective hematopoietic stem cells (HSCs) due to niche-dependent differentiation defects. Here we report that immature HSCs coexpress c-myc and N-myc mRNA at similar levels. Although conditional deletion of N-myc in the bone marrow does not affect hematopoiesis, combined deficiency of c-Myc and N-Myc (dKO) results in pancytopenia and rapid lethality. Interestingly, proliferation of HSCs depends on both myc genes during homeostasis, but is c-Myc/N-Myc independent during bone marrow repair after injury. Strikingly, while most dKO hematopoietic cells undergo apoptosis, only self-renewing HSCs accumulate the cytotoxic molecule Granzyme B, normally employed by the innate immune system, thereby revealing an unexpected mechanism of stem cell apoptosis. Collectively, Myc activity (c-Myc and N-Myc) controls crucial aspects of HSC function including proliferation, differentiation, and survival.


Assuntos
Diferenciação Celular/genética , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Animais , Linhagem da Célula/genética , Proliferação de Células , Sobrevivência Celular/genética , Células Cultivadas , Sobrevivência de Enxerto/genética , Granzimas/metabolismo , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/citologia , Camundongos , Camundongos Knockout , Pancitopenia/genética , Pancitopenia/fisiopatologia , Transdução de Sinais/genética , Estresse Fisiológico/genética
15.
Mol Cell Biol ; 25(16): 7078-91, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16055719

RESUMO

The Myc-Max-Mad/Mnt network of transcription factors has been implicated in oncogenesis and the regulation of proliferation in vertebrate cells. The identification of Myc and Max homologs in Drosophila melanogaster has demonstrated a critical role for dMyc in cell growth control. In this report, we identify and characterize the third member of this network, dMnt, the sole fly homolog of the mammalian Mnt and Mad family of transcriptional repressors. dMnt possesses two regions characteristic of Mad and Mnt proteins: a basic helix-loop-helix-zipper domain, through which it dimerizes with dMax to form a sequence-specific DNA binding complex, and a Sin-interacting domain, which mediates interaction with the dSin3 corepressor. Using the upstream activation sequence/GAL4 system, we show that expression of dMnt results in an inhibition of cellular growth and proliferation. Furthermore, we have generated a dMnt null allele, which results in flies with larger cells, increased weight, and decreased life span compared to wild-type flies. Our results demonstrate that dMnt is a transcriptional repressor that regulates D. melanogaster body size.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Proteínas Repressoras/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Alelos , Processamento Alternativo , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Tamanho Corporal , Proliferação de Células , Separação Celular , DNA/metabolismo , Dimerização , Drosophila melanogaster/fisiologia , Citometria de Fluxo , Glutationa Transferase/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Imuno-Histoquímica , Insulina/metabolismo , Longevidade , Modelos Genéticos , Mutação , Fenótipo , Filogenia , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Repressoras/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Transcrição Gênica , Técnicas do Sistema de Duplo-Híbrido
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