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1.
Sci Rep ; 14(1): 10085, 2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698166

RESUMO

The North China Plain (NCP) is one of the three great plains in China and also serves as a vital region for grain, cotton, and oil production. Under the influence of regional hydrothermal changes, groundwater overexploitation, and seawater intrusion, the vegetation coverage is undergoing continuous alterations. However, a comprehensive assessment of impacts of precipitation, temperature, and groundwater on vegetation in marine sedimentary regions of the NCP is lacking. Heilonggang Basin (HB) is located in the low-lying plain area in the east of NCP, which is part of the NCP. In this study, the HB was chosen as a typical area of interest. We collected a series of data, including the Normalized Difference Vegetation Index (NDVI), precipitation, temperature, groundwater depth, and Total Dissolved Solids (TDS) from 2001 to 2020. Then the spatiotemporal variation in vegetation was analyzed, and the underlying driving mechanisms of vegetation variation were explored in this paper. The results show that NDVI experiences a rapid increase from 2001 to 2004, followed by stable fluctuations from 2004 to 2020. The vegetation in the HB has achieved an overall improvement in the past two decades, with 76% showing improvement, mainly in the central and eastern areas, and 24% exhibiting deterioration in other areas. From 2001 to 2020, NDVI correlates positively with precipitation, whereas its relationship with temperature fluctuates between positive and negative, and is not statistically significant. There is a threshold for the synergistic change of NDVI and groundwater depth. When the groundwater depth is lower than 3.8 m, NDVI increases sharply with groundwater depth. However, beyond this threshold, NDVI tends to stabilize and fluctuate. In the eastern coastal areas, NDVI exhibits a strong positive correlation with groundwater depth, influenced by the surface soil TDS controlled by groundwater depth. In the central regions, a strong negative correlation is observed, where NDVI is primarily impacted by soil moisture under the control of groundwater. In the west and south, a strong positive correlation exists, with NDVI primarily influenced by the intensity of groundwater exploitation. Thus, precipitation and groundwater are the primary driving forces behind the spatiotemporal variability of vegetation in the HB, while in contrast, the influence of temperature is uncertain. This study has elucidated the mechanism of vegetation response, providing a theoretical basis for mitigating adverse factors affecting vegetation growth and formulating rational water usage regulations in the NCP.


Assuntos
Água Subterrânea , China , Água Subterrânea/análise , Sedimentos Geológicos/análise , Temperatura , Análise Espaço-Temporal , Monitoramento Ambiental/métodos , Clima , Plantas , Ecossistema
2.
IEEE Trans Cybern ; PP2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578861

RESUMO

The utilization of robots in computer, communication, and consumer electronics (3C) assembly has the potential to significantly reduce labor costs and enhance assembly efficiency. However, many typical scenarios in 3C assembly, such as the assembly of flexible printed circuits (FPCs), involve complex manipulations with long-horizon steps and high-precision requirements that cannot be effectively accomplished through manual programming or conventional skill-learning methods. To address this challenge, this article proposes a learning-based framework for the acquisition of complex 3C assembly skills assisted by a multimodal digital-twin environment. First, we construct a fully equivalent digital-twin environment based on the real-world counterpart, equipped with visual, tactile force, and proprioception information, and then collect multimodal demonstration data using virtual reality (VR) devices. Next, we construct a skill knowledge base through multimodal skill parsing of demonstration data, resulting in primitive policy sequences for achieving 3C assembly tasks. Finally, we train primitive policies via a combination of curriculum learning, residual reinforcement learning, and domain randomization methods and transfer the learned skill from the digital-twin environment to the real-world environment. The experiments are conducted to verify the effectiveness of our proposed method.

3.
Mater Today Bio ; 25: 100993, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38440110

RESUMO

Osteoarthritis (OA) is a chronic inflammatory joint disease characterized by progressive cartilage degeneration, synovitis, and osteoid formation. In order to effectively treat OA, it is important to block the harmful feedback caused by reactive oxygen species (ROS) produced during joint wear. To address this challenge, we have developed injectable nanocomposite hydrogels composed of polygallate-Mn (PGA-Mn) nanoparticles, oxidized sodium alginate, and gelatin. The inclusion of PGA-Mn not only enhances the mechanical strength of the biohydrogel through a Schiff base reaction with gelatin but also ensures efficient ROS scavenging ability. Importantly, the nanocomposite hydrogel exhibits excellent biocompatibility, allowing it to effectively remove ROS from chondrocytes and reduce the expression of inflammatory factors within the joint. Additionally, the hygroscopic properties of the hydrogel contribute to reduced intra-articular friction and promote the production of cartilage-related proteins, supporting cartilage synthesis. In vivo experiments involving the injection of nanocomposite hydrogels into rat knee joints with an OA model have demonstrated successful reduction of osteophyte formation and protection of cartilage from wear, highlighting the therapeutic potential of this approach for treating OA.

4.
Int J Biol Macromol ; 264(Pt 1): 130411, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38437932

RESUMO

Bamboo has tremendous carbon sequestration potential, and bamboo green is underutilized. This work devised a green-keeping technique in bamboo flattening that preserved natural bamboo green in-situ. The impacts of flattening and green-keeping on bamboo morphology, chemical composition, physical qualities, and composite applications were examined. Bamboo cells were wrinkled after flattening, while bamboo green exhibited a more homogenous surface. Bamboo cellulose crystallinity increased after flattening, hemicellulose deteriorated little, and relative lignin content increased. The hydrophobicity and mildew resistance of the surface of G-FB (green-kept flattened bamboo board) were improved. Compared to untreated bamboo, FB and G-FB had 61.1 % and 49.5 % higher tensile strength and 8.0 % and 33.2 % higher MOR. G-FB-made flooring exhibited a MOR of 134.7 MPa and upgraded surface properties. Bamboo green preservation boosted utilization of materials and improved flattened bamboo's exterior surface without affecting lamination bonding. Simple bamboo green preservation multifunctionalizes flattened bamboo composites.


Assuntos
Celulose , Lignina , Lignina/química , Celulose/química , Propriedades de Superfície , Resistência à Tração
5.
Small ; 20(13): e2308167, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37953455

RESUMO

Intervertebral disc degeneration (IVDD) is a significant contributor to low back pain, characterized by excessive reactive oxygen species generation and inflammation-induced pyroptosis. Unfortunately, there are currently no specific molecules or materials available to effectively delay IVDD. This study develops a multifunctional full name of PG@Cu nanoparticle network (PG@Cu). A designed pentapeptide, bonded on PG@Cu nanoparticles via a Schiff base bond, imparts multifunctionality to the metal polyphenol particles (PG@Cu-FP). PG@Cu-FP exhibits enhanced escape from lysosomal capture, enabling efficient targeting of mitochondria to scavenge excess reactive oxygen species. The scavenging activity against reactive oxygen species originates from the polyphenol-based structures within the nanoparticles. Furthermore, Pyroptosis is effectively blocked by inhibiting Gasdermin mediated pore formation and membrane rupture. PG@Cu-FP successfully reduces the activation of the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 inflammasome by inhibiting Gasdermin protein family (Gasdermin D, GSDMD) oligomerization, leading to reduced expression of Nod-like receptors. This multifaceted approach demonstrates higher efficiency in inhibiting Pyroptosis. Experimental results confirm that PG@Cu-FP preserves disc height, retains water content, and preserves tissue structure. These findings highlight the potential of PG@Cu-FP in improving IVDD and provide novel insights for future research in IVDD treatments.


Assuntos
Degeneração do Disco Intervertebral , Nanopartículas , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Degeneração do Disco Intervertebral/tratamento farmacológico , Degeneração do Disco Intervertebral/metabolismo , Gasderminas , Inflamassomos/metabolismo , Mitocôndrias/metabolismo , Polifenóis/farmacologia
6.
Front Nutr ; 10: 1275199, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781120

RESUMO

Aging is a universal and irreversible process, and the skin is an important feature that reflects the aging of the organism. Skin aging has been a focus of attention in recent years because it leads to changes in an individual's external features and the loss of many important biological functions. This experiment investigated the improvement effect of black tea extract (BTE) on the skin of aging mice under D-galactose induction. After 6 weeks of administration, the changes in skin bio-chemical indices and tissue structure were compared with the blank and positive control groups. It was observed that BTE increased water and hyaluronic acid (HA) content, decreased malondialdehyde (MDA) content, enhanced superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities in the skin of aging mice, and improved the structure of aging damaged skin tissues and increased the content of total collagen. The experimental results showed that BTE can play a significant anti-aging effect on the skin, which can be used as a functional food for aging inhibition.

7.
Sci Rep ; 13(1): 8977, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37268658

RESUMO

Dilated cardiomyopathy (DCM) is a common cause of heart failure, and males are more likely to suffer from DCM than females. This research aimed at exploring possible DCM-associated genes and their latent regulatory effects in female and male patients. WGCNA analysis found that in the yellow module, 341 and 367 key DEGs were identified in females and males, respectively. A total of 22 hub genes in females and 17 hub genes in males were identified from the PPI networks of the key DEGs based on Metascape database. And twelve and eight potential TFs of the key DEGs were also identified in females and males, respectively. Eight miRNAs of 15 key DEGs were screened in both females and males, which may be differentially expressed in females and males. Dual-luciferase reporter assay demonstrated that miR-21-5P could directly target the key gene MATN2. Furthermore, Sex differences in KEGG pathways were identified. Both KOBAS and GSEA analysis identified 19 significantly enriched pathways related to immune response in both females and males, and the TGF-ß signaling pathway was exclusively identified in males. Network pharmacology analysis revealed that seven key DEGs were potential targets for the treatment of DCM, of which the OLR1 gene was only identified in males, the expression levels of the seven genes were verified by RT-PCR. The above results could offer a novel understanding of sex differences in key genes and pathways in DCM progression.


Assuntos
Cardiomiopatia Dilatada , Insuficiência Cardíaca , MicroRNAs , Humanos , Feminino , Masculino , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/metabolismo , Perfilação da Expressão Gênica/métodos , MicroRNAs/genética , Biologia Computacional/métodos , Redes Reguladoras de Genes
8.
Materials (Basel) ; 16(8)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37109990

RESUMO

The variety of conductive fibers has been constantly enriched in recent years, and it has made rapid development in the fields of electronic textiles, intelligent wearable, and medical care. However, the environmental damage caused by the use of large quantities of synthetic fibers cannot be ignored, and there is little research on conductive fibers in the field of bamboo, a green and sustainable material. In this work, we used the alkaline sodium sulfite method to remove lignin from bamboo, prepared a conductive bamboo fiber bundle by coating a copper film on single bamboo fiber bundles using DC magnetron sputtering, and analyzed its structure and physical properties under different process parameters, finding the most suitable preparation condition that combines cost and performance. The results of the scanning electron microscope show that the coverage of copper film can be improved by increasing the sputtering power and prolonging the sputtering time. The resistivity of the conductive bamboo fiber bundle decreased with the increase of the sputtering power and sputtering time, up to 0.22 Ω·mm; at the same time, the tensile strength of the conductive bamboo fiber bundle continuously decreased to 375.6 MPa. According to the X-ray diffraction results, Cu in the copper film on the surface of the conductive bamboo fiber bundle shows the preferred orientation of (111) the crystal plane, indicating that the prepared Cu film has high crystallinity and good film quality. X-ray photoelectron spectroscopy results show that Cu in the copper film exists in the form of Cu0 and Cu2+, and most are Cu0. Overall, the development of the conductive bamboo fiber bundle provides a research basis for the development of conductive fibers in a natural renewable direction.

9.
Environ Res ; 229: 115964, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37100363

RESUMO

Wood is an insulator material, using its porous structure to endow it with efficient microwave absorption and broaden its application range is still a major challenge. Here, wood-based Fe3O4 composites with excellent microwave absorption properties and high mechanical strength were prepared by alkaline sulfite method, in-situ co-precipitation method and compression densification method. The results showed that the magnetic Fe3O4 was densely deposited in the wood cells, and the prepared wood-based microwave absorption composites had both high electrical conductivity, magnetic loss, excellent impedance matching performance and attenuation performance, as well as effective microwave absorption properties. In the frequency range of 2-18 GHz, the minimum reflection loss value was -25.32 dB. At the same time, it had high mechanical properties. Compared with the untreated wood, its modulus of elasticity (MOE) in bending increased by 98.77%, and modulus of rapture (MOR) in bending improved by 67.9%. The developed wood-based microwave absorption composite is expected to be used in electromagnetic shielding fields such as anti-radiation and anti-interference.


Assuntos
Óxido Ferroso-Férrico , Madeira , Campos Eletromagnéticos , Micro-Ondas , Porosidade
10.
Nutrients ; 15(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36986268

RESUMO

Each person's body is host to a large number and variety of gut microbiota, which has been described as the second genome and plays an important role in the body's metabolic process and is closely related to health. It is common knowledge that proper physical activity and the right diet structure can keep us healthy, and in recent years, researchers have found that this boost to health may be related to the gut microbiota. Past studies have reported that physical activity and diet can modulate the compositional structure of the gut microbiota and further influence the production of key metabolites of the gut microbiota, which can be an effective way to improve body metabolism and prevent and treat related metabolic diseases. In this review, we outline the role of physical activity and diet in regulating gut microbiota and the key role that gut microbiota plays in improving metabolic disorders. In addition, we highlight the regulation of gut microbiota through appropriate physical exercise and diet to improve body metabolism and prevent metabolic diseases, aiming to promote public health and provide a new approach to treating such diseases.


Assuntos
Microbioma Gastrointestinal , Doenças Metabólicas , Humanos , Microbioma Gastrointestinal/fisiologia , Dieta , Exercício Físico/fisiologia , Doenças Metabólicas/prevenção & controle
11.
Polymers (Basel) ; 14(24)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36559831

RESUMO

Bamboo has become an important kind of fibrous raw material in the world due to its fast-growing property and abundance of natural fiber. During the purification and utilization of bamboo fiber, the removal of lignin is vital and it is affected by the chemical treatment system and drying method. In this paper, the effects of three different delignification chemical systems and three drying methods (air drying, drying and freeze drying) on the physical and chemical properties of bamboo fiber were comparatively studied. The results prove that all three delignification techniques can effectively remove lignin from wood, and by utilizing peroxyformic acid and alkaline sodium sulfite, hemicellulose can be removed to a certain extent. With the selective removal of amorphous hemicellulose and lignin and the hydrolysis of cellulose molecular chains in amorphous regions, all three treatments contributed to an increase in the relative crystallinity of cellulose (ranging from 55% to 60%). Moreover, it was found that the drying methods exerted a certain influence on the mechanical properties of fiber. For instance, drying or air drying would improve the tensile strength of fiber significantly, approximately 2-3.5 times that of original bamboo fiber, and the tensile strength of the drying group reached 850-890 MPa. In addition, the alkaline sodium sulfite treatment had little effect on the thermal stability of bamboo fiber, resulting in high thermal stability of the prepared samples, and the residual mass reached 25-37%. On the contrary, the acetic acid/hydrogen peroxide method exerted great influence on the thermal stability of bamboo fiber, giving rise to a relatively poor thermal stability of prepared fibers, and the residual mass was only about 15%. Among the three drying methods, samples under air drying treatment had the highest residual mass, while those under freeze drying had the lowest. To summarize, the alkaline sodium sulfite method is more suitable for preparing bamboo fiber with higher tensile strength and thermal stability.

12.
Foods ; 11(19)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36230037

RESUMO

Intestinal flora is numerous and diverse, and play a key role in maintaining human health. Dietary polysaccharides are widely present in the daily diet and have a moderating effect on the intestinal flora. Past studies have confirmed that intestinal flora is involved in the metabolic process in the human body, and the change in intestinal flora structure is closely related to the metabolic disorders in the human body. Therefore, regulating intestinal flora through dietary polysaccharides is an effective way to treat and prevent common metabolic diseases and has great research value. However, this area has not received enough attention. In this review, we provide an overview of the modulatory effects of dietary polysaccharides on intestinal flora and the key role of intestinal flora in improving metabolic disorders in humans. In addition, we highlight the therapeutic and preventive effects of intestinal flora modulation through dietary polysaccharides on metabolic disorders, aiming to find new ways to treat metabolic disorders and facilitate future exploration in this field.

13.
Artigo em Inglês | MEDLINE | ID: mdl-36185091

RESUMO

Tongue diagnosis is a convenient and noninvasive clinical practice of traditional Chinese medicine (TCM), having existed for thousands of years. Prickle, as an essential indicator in TCM, appears as a large number of red thorns protruding from the tongue. The term "prickly tongue" has been used to describe the flow of qi and blood in TCM and assess the conditions of disease as well as the health status of subhealthy people. Different location and density of prickles indicate different symptoms. As proved by modern medical research, the prickles originate in the fungiform papillae, which are enlarged and protrude to form spikes like awn. Prickle recognition, however, is subjective, burdensome, and susceptible to external factors. To solve this issue, an end-to-end prickle detection workflow based on deep learning is proposed. First, raw tongue images are fed into the Swin Transformer to remove interference information. Then, segmented tongues are partitioned into four areas: root, center, tip, and margin. We manually labeled the prickles on 224 tongue images with the assistance of an OpenCV spot detector. After training on the labeled dataset, the super-resolutionfaster-RCNN extracts advanced tongue features and predicts the bounding box of each single prickle. We show the synergy of deep learning and TCM by achieving a 92.42% recall, which is 2.52% higher than the previous work. This work provides a quantitative perspective for symptoms and disease diagnosis according to tongue characteristics. Furthermore, it is convenient to transfer this portable model to detect petechiae or tooth-marks on tongue images.

14.
Polymers (Basel) ; 14(17)2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36080719

RESUMO

Bamboo is one of the most promising biomass materials in the world. However, the poor anti-mildew property and poor dimensional stability limits its outdoor applications. Current scholars focus on the modification of bamboo through heat treatment. Arc-shaped bamboo sheets are new bamboo products for special decoration in daily life. In this paper, we reported pressure-steam heat treatment and explored the effect of pressure-steam on the micro-structure, crystallinity index, anti-mildew, chemical composition, physical properties, and mechanical properties of bamboo via X-ray diffractometer (XRD), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), wet chemistry method and nanoindentation (NI). Herein, saturated-steam heat treatment was applied for modified moso bamboo for enhancing the anti-mildew properties and mechanical properties of moso bamboo. Results showed that with the introduction of saturated steam, the content of hemicellulose and cellulose decreased, while the lignin-relative content increased significantly. The anti-mildew property of moso bamboo was enhanced due to the decomposition of polysaccharide. Last, the modulus of elasticity and hardness of treated moso bamboo cell walls were enhanced after saturated-steam heat treatment. For example, the MOE of the treated moso bamboo cell wall increased from 12.7 GPa to 15.7 GPa. This heat treatment strategy can enhance the anti-mildew property of moso bamboo and can gain more attention from entrepreneurs and scholars.

15.
Front Microbiol ; 13: 807076, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35369451

RESUMO

The intestinal tract of a healthy body is home to a large variety and number of microorganisms that will affect every aspect of the host's life. In recent years, polysaccharides have been found to be an important factor affecting intestinal flora. Polysaccharides are widely found in nature and play a key role in the life activities of living organisms. In the intestinal tract of living organisms, polysaccharides have many important functions, such as preventing the imbalance of intestinal flora and maintaining the integrity of the intestinal barrier. Moreover, recent studies suggest that gut microbes can influence brain health through the brain-gut axis. Therefore, maintaining brain health through polysaccharide modulation of gut flora deserves further study. In this review, we outline the mechanisms by which polysaccharides maintain normal intestinal flora structure, as well as improving cognitive function in the brain via the brain-gut axis by virtue of the intestinal flora. We also highlight the important role that gut microbes play in the pathogenesis of depression and the potential for treating depression through the use of polysaccharides to modulate the intestinal flora.

16.
Mol Biol Rep ; 49(5): 3675-3684, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35179668

RESUMO

BACKGROUND: DSH-20, the active ingredient of Salvia miltiorrhiza flower extract, is used to treat cardiovascular diseases. However, its mechanism of action remains unclear. Herein, we investigated the intervention of DSH-20 in H2O2-induced oxidative damage and apoptosis in cardiomyocytes. METHODS AND RESULTS: H2O2 was used to induce oxidative damage and apoptosis in H9c2 cardiomyocytes. Based on concentration gradient studies, we found that 62.5 µg/mL DSH-20 significantly reduced reactive oxygen species and lactate dehydrogenase levels and increased superoxide dismutase levels. DSH-20 also alleviated the apoptosis rate, the changes in mRNA of apoptosis-related genes (Bcl-2, BAX, and Caspase-3) and miR-1 expression. Moreover, transfection of miR-1 mimics aggravated oxidative damage and apoptosis, whereas DSH-20 alleviated these effects. CONCLUSIONS: DSH-20 reduced H2O2-induced oxidative damage and apoptosis in H9c2 cardiomyocytes likely by downregulating miR-1 expression.


Assuntos
MicroRNAs , Salvia miltiorrhiza , Apoptose , Flores/metabolismo , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , MicroRNAs/metabolismo , Miócitos Cardíacos/metabolismo , Estresse Oxidativo , Salvia miltiorrhiza/genética , Salvia miltiorrhiza/metabolismo
17.
Polymers (Basel) ; 14(4)2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-35215729

RESUMO

In this paper, we introduced a bamboo longitudinal flattening technology and analyzed the effects of the softening-flattening process on the physical and mechanical properties of moso bamboo. This is a newer bamboo processing technology that can enhance the utilization and reduce pollution compared with traditional bamboo-based products. Results showed that the parenchyma cells distorted and compacted due to the flattening process. The hemicellulose and cellulose content decreased, while the content of lignin presented an increasing tendency. As expected, the dimensional stability of moso bamboo enhanced due to the decrement of hemicellulose. The softening-flattening process positively contributed to the micro-mechanical properties of treated bamboo specimens. For example, the hardness and modulus of elasticity of the untreated bamboo sample increased from 0.58 and 15.7 GPa to 0.8 and 17.5 GPa, respectively. In addition, the changes in cellulose crystallinity and mechanical properties were also investigated in this paper. The cellulose crystallinity increased from 37.5% to 43.2%, significantly. However, the modulus of rupture of the flattened bamboo board decreased from 9000 to 7500 MPa due to the grooves made by the flattening roller. The MOE of flattening bamboo board showed the same decreasing tendency.

18.
Polymers (Basel) ; 14(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35160635

RESUMO

In recent years, saturated steam heat treatment has been considered as an environmentally friendly and cost-effective modification method compared with traditional heat treatment media. In this study, bamboo was treated by saturated steam, and the change in chemical composition, cellulose crystallinity index, micro-morphology, and micromechanical properties were analyzed by a wet chemistry method, Fourier transform infrared (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), nanoindentation, and so on. Results illustrated that the parenchyma cell walls were distorted due to the decomposition of hemicellulose and cellulose in bamboo samples. As expected, the hemicellulose and cellulose content decreased, whereas the lignin content increased significantly. In addition, the cellulose crystallinity index and thus the micromechanical properties of bamboo cell walls increased. For example, the hardness increased from 0.69 GPa to 0.84 GPa owing to the enhanced crystallinity index and lignin content.

19.
Antioxidants (Basel) ; 11(2)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35204136

RESUMO

The intestinal tract of a healthy human body hosts many microorganisms that are closely linked to all aspects of people's lives. The impact of intestinal flora on host health is no longer limited to the gut but can also affect every organ in the body through various pathways. Studies have found that intestinal flora can be altered by external factors, which provides new ideas for treating some diseases. Tea polyphenols (TP), a general term for polyphenols in tea, are widely used as a natural antioxidant in various bioactive foods. In recent years, with the progress of research, there have been many experiments that provide strong evidence for the ability of TP to regulate intestinal flora. However, there are very few studies on the use of TP to modify the composition of intestinal microorganisms to maintain health or treat related diseases, and this area has not received sufficient attention. In this review, we outline the mechanisms by which TP regulates intestinal flora and the essential role in maintaining suitable health. In addition, we highlighted the protective effects of TP on intestinal mucosa by regulating intestinal flora and the preventive and therapeutic effects on certain chronic diseases, which will help further explore measures to prevent related chronic diseases.

20.
Exp Cell Res ; 409(2): 112925, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34785240

RESUMO

Promoting angiogenesis by targeting various angiogenic regulators has emerged as a new treatment strategy for myocardial ischemia (MI). MicroRNA-126 (miR-126) has been identified as the main regulator of compensatory angiogenesis; however, its role in MI is unclear. A rat MI model and an EA. hy926 endothelial cell hypoxia model were constructed and it was found that miR-126 was highly expressed in both models. The knockdown of HIF-1α expression in EA. hy926 cells in turn downregulated VEGF and CD34 expression and consequently inhibited angiogenesis. MiR-126 inhibitor inhibited EA. hy926 cell migration and tube formation as well as downregulated VEGF and CD34 expression, and these were reversed by transfection of miR-126 mimics. Rescue tests using miR-126 and HIF-1α demonstrated that miR-126-mediated regulation of angiogenesis was dependent on HIF-1α. In summary, miR-126 regulates the occurrence and progression of angiogenesis during MI via HIF-1α and may be a potential new therapeutic target.


Assuntos
Antígenos CD34/química , Células Endoteliais/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , MicroRNAs/genética , Isquemia Miocárdica/patologia , Neovascularização Patológica/patologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Antígenos CD34/genética , Antígenos CD34/metabolismo , Hipóxia Celular , Células Endoteliais/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Isquemia Miocárdica/genética , Isquemia Miocárdica/metabolismo , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
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