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1.
Plant Physiol Biochem ; 211: 108684, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710113

RESUMO

Abscisic acid-, stress-, and ripening-induced (ASR) proteins in plants play a significant role in plant response to diverse abiotic stresses. However, the functions of ASR genes in maize remain unclear. In the present study, we identified a novel drought-induced ASR gene in maize (ZmASR1) and functionally characterized its role in mediating drought tolerance. The transcription of ZmASR1 was upregulated under drought stress and abscisic acid (ABA) treatment, and the ZmASR1 protein was observed to exhibit nuclear and cytoplasmic localization. Moreover, ZmASR1 knockout lines generated with the CRISPR-Cas9 system showed lower ROS accumulation, higher ABA content, and a higher degree of stomatal closure than wild-type plants, leading to higher drought tolerance. Transcriptome sequencing data indicated that the significantly differentially expressed genes in the drought treatment group were mainly enriched in ABA signal transduction, antioxidant defense, and photosynthetic pathway. Taken together, the findings suggest that ZmASR1 negatively regulates drought tolerance and represents a candidate gene for genetic manipulation of drought resistance in maize.

2.
Angew Chem Int Ed Engl ; : e202404388, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38641988

RESUMO

Photoinduced Pd-catalyzed bisfunctionalization of butadienes with a readily available organic halide and a nucleophile represents an emerging and attractive method to assemble versatile alkenes bearing various functional groups at the allylic position. However, enantiocontrol and/or diastereocontrol in the C-C or C-X bond-formation step have not been solved due to the open-shell process. Herein, we present a cascade asymmetric dearomatization reaction of indoles via photoexcited Pd-catalyzed 1,2-biscarbonfunctionalization of 1,3-butadienes, wherein asymmetric control on both the nucleophile and electrophile part is achieved for the first time in photoinduced bisfunctionalization of butadienes. This method delivers structurally novel chiral spiroindolenines bearing two contiguous stereogenic centers with high diastereomeric ratios (up to >20:1 dr) and good to excellent enantiomeric ratios (up to 97:3 er). Experimental and computational studies of the mechanism have confirmed a radical pathway involving excited-state palladium catalysis. The alignment and non-covalent interactions between the substrate and the catalyst were found to be essential for stereocontrol.

3.
Support Care Cancer ; 32(4): 237, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509239

RESUMO

PURPOSE: Surgery for esophageal squamous cell carcinoma (ESCC) is characterized by a poor prognosis and high complication rate, resulting in a heavy symptom burden and poor health-related quality of life (QOL). We evaluated longitudinal patient-reported outcomes (PROs) to analyze the correlations between symptoms and QOL and their changing characteristics during postoperative rehabilitation. METHODS: We investigated patients with ESCC who underwent minimally invasive McKeown esophagectomy at Sichuan Cancer Hospital between April 2019 and December 2019. Longitudinal data of the clinical characteristics and PROs were collected. The MD Anderson Symptom Inventory and European Organization for Research and Treatment of Cancer (EORTC) QOL questionnaires were used to assess symptoms and QOL and compare the trajectories of PROs during the investigation. RESULTS: A total of 244 patients with ESCC were enrolled in this study. Regarding QOL, role and emotional functions returned to baseline at 1 month after surgery, and cognitive and social functions returned to baseline at 3 months after surgery. However, physical function and global QOL did not return to baseline at 1 year after surgery. At 7 days and 1, 3, 6, and 12 months after surgery, the main symptoms of the patients were negatively correlated with physical, role, emotional, cognitive, and social functions and the overall health status (P < 0.05). CONCLUSION: Patients with ESCC experience reduced health-related QOL and persisting symptoms after minimally invasive McKeown esophagectomy, but a recovery trend was observed within 1 month. The long-term QOL after esophagectomy is acceptable.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/cirurgia , Carcinoma de Células Escamosas do Esôfago/complicações , Qualidade de Vida , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/patologia , Esofagectomia/efeitos adversos , Exame Físico , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Resultado do Tratamento
4.
J Am Chem Soc ; 146(8): 5081-5087, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38358355

RESUMO

The asymmetric hydrogenation (AH) of N-unprotected indoles is a straightforward, yet challenging method to access biologically interesting NH chiral indolines. This method has for years been limited to 2/3-monosubstituted or 2,3-disubstituted indoles, which produce chiral indolines bearing endocyclic chiral centers. Herein, we have reported an innovative Pd-catalyzed AH of racemic α-alkyl or aryl-substituted indole-2-acetates using an acid-assisted dynamic kinetic resolution (DKR) process, affording a range of structurally fascinating chiral indolines that contain exocyclic stereocenters with excellent yields, diastereoselectivities, and enantioselectivities. Mechanistic studies support that the DKR process relies on a rapid interconversion of each enantiomer of racemic substrates, leveraged by an acid-promoted isomerization between the aromatic indole and nonaromatic exocyclic enamine intermediate. The reaction can be performed on a gram scale, and the products can be derivatized into non-natural ß-amino acids via facile debenzylation and amino alcohol upon reduction.

5.
Int J Microbiol ; 2024: 6631882, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38229736

RESUMO

Influenza pandemic with H1N1 (H1N1pdms) causes severe lung damage and "cytokine storm," leading to higher mortality and global health emergencies in humans and animals. Explaining host antiviral molecular mechanisms in response to H1N1pdms is important for the development of novel therapies. In this study, we organised and analysed multimicroarray data for mouse lungs infected with different H1N1pdm and nonpandemic H1N1 strains. We found that H1N1pdms infection resulted in a large proportion of differentially expressed genes (DEGs) in the infected lungs compared with normal lungs, and the number of DEGs increased markedly with the time of infection. In addition, we found that different H1N1pdm strains induced similarly innate immune responses and the identified DEGs during H1N1pdms infection were functionally concentrated in defence response to virus, cytokine-mediated signalling pathway, regulation of innate immune response, and response to interferon. Moreover, comparing with nonpandemic H1N1, we identified ten distinct DEGs (AREG, CXCL13, GATM, GPR171, IFI35, IFI47, IFIT3, ORM1, RETNLA, and UBD), which were enriched in immune response and cell surface receptor signalling pathway as well as interacted with immune response-related dysregulated genes during H1N1pdms. Our discoveries will provide comprehensive insights into host responding to pandemic with influenza H1N1 and find broad-spectrum effective treatment.

6.
Biomater Sci ; 12(4): 1016-1030, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38206081

RESUMO

Nano-biointerfaces play a pivotal role in determining the functionality of engineered therapeutic nanoparticles, particularly in the context of designing nanovaccines to effectively activate immune cells for cancer immunotherapy. Unlike involving chemical reactions by conventional surface decorating strategies, cell membrane-coating technology offers a straightforward approach to endow nanoparticles with natural biosurfaces, enabling them to mimic and integrate into the intricate biosystems of the body to interact with specific cells under physiological conditions. In this study, cell membranes, in a hybrid formulation, derived from cancer and activated macrophage cells were found to enhance the interaction of nanoparticles (HMP) with dendritic cells (DCs) and T cells among the mixed immune cells from lymph nodes (LNs), which could be leveraged in the development of nanovaccines for anti-tumor therapy. After loading with an adjuvant (R837), the nanoparticles coated with a hybrid membrane (HMPR) demonstrated effectiveness in priming DCs both in vitro and in vivo, resulting in amplified anti-tumor immune responses compared to those of nanoparticles coated with a single type of membrane or those lacking a membrane coating. The elevated immunoactivity of nanoparticles achieved by incorporating a hybrid membrane biosurface provides us a more profound comprehension of the nano-immune interaction, which may significantly benefit the development of bioactive nanomaterials for advanced therapy.


Assuntos
Nanopartículas , Neoplasias , Humanos , Neoplasias/terapia , Membrana Celular , Imunoterapia , Células Dendríticas , Imunidade
7.
Ambio ; 52(12): 1928-1938, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37907802

RESUMO

Ecological civilization has emerged as an innovative form of civilization in China, and sustainable development has been widely recognized as a globally leading development model. These two concepts are closely related. The international English literature focuses on hot topics in the field of sustainable development such as climate change, urbanization, government management, and ecosystems, while the Chinese literature emphasizes ecological civilization concepts with Chinese characteristics, such as green development, beautiful China, and scientific development concepts. Ecological civilization and sustainable development are both responses to resource, environmental, and ecological crises and have emerged from the same historical background. The two concepts complement each other, with ecological civilization providing an ideological foundation for sustainable development, and sustainable development serving as the implementation path and concrete manifestation of ecological civilization. To deepen research on ecological civilization and sustainable development, it is necessary to build a global community with a shared future, address the major strategic needs of different countries or regions, innovate and develop interdisciplinary theories, methods, and technologies, strengthen international cooperation, provide disciplinary support for ecological civilization and sustainable development research, and provide country-specific research solutions for global and regional sustainable development.


Assuntos
Ecossistema , Desenvolvimento Sustentável , Bibliometria , Cooperação Internacional , China , Civilização , Conservação dos Recursos Naturais
8.
Materials (Basel) ; 16(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37895618

RESUMO

In recent years, with the fast development of the technology and the economy associated with the growth of the global population, the construction of economical, sustainable, and eco-friendly infrastructures with improved ductility, resistance to external elements, and durability has increased the need for the development of high-performance construction materials [...].

9.
Pharm Biol ; 61(1): 1401-1412, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37667488

RESUMO

CONTEXT: Panax japonicus is the dried rhizome of Panax japonicus C.A. Mey. (Araliaceae). Saponins from Panax japonicus (SPJ) exhibit anti-oxidative and anti-aging effects. OBJECTIVE: We evaluated the neuroprotective effects of SPJ on aging rats. MATERIALS AND METHODS: Sprague-Dawley rats (18-months-old) were randomly divided into aging and SPJ groups (n = 8). Five-month-old rats were taken as the adult control (n = 8). The rats were fed a normal chow diet or the SPJ-containing diet (10 or 30 mg/kg) for 4 months. An in vitro model was established by d-galactose (d-Gal) in the SH-SY5Y cell line and pretreated with SPJ (25 and 50 µg/mL). The neuroprotection of SPJ was evaluated via Nissl staining, flow cytometry, transmission electron microscopy and Western blotting in vivo and in vitro. RESULTS: SPJ improved the neuronal degeneration and mitochondrial morphology that are associated with aging. Meanwhile, SPJ up-regulated the protein levels of mitofusin 2 (Mfn2) and optic atrophy 1 (Opa1) and down-regulated the protein level of dynamin-like protein 1 (Drp1) in the hippocampus of aging rats (p < 0.05 or p < 0.01 vs. 22 M). The in vitro studies also demonstrated that SPJ attenuated d-Gal-induced cell senescence concomitant with the improvement in mitochondrial function; SPJ, also up-regulated the Mfn2 and Opa1 protein levels, whereas the Drp1 protein level (p < 0.05 or p < 0.01 vs. d-Gal group) was down-regulated. DISCUSSION AND CONCLUSIONS: Further research on the elderly population will contribute to the development and utilization of SPJ for the treatment of neurodegenerative disorders.


Assuntos
Neuroblastoma , Panax , Idoso , Humanos , Ratos , Animais , Ratos Sprague-Dawley , Envelhecimento , Galactose , Mitocôndrias
10.
Food Chem Toxicol ; 180: 114033, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37739053

RESUMO

The interplay between cell apoptosis and endoplasmic reticulum (ER) stress has garnered increasing attention. Nevertheless, the precise involvement of the unfolded protein response (UPR) signaling in the apoptosis of porcine macrophage cells induced by Deoxynivalenol (DON) remains enigmatic. In this study, we revealed that exposure to 2 µM DON resulted in a substantial decline in cell viability, concomitant with the initiation of cell apoptosis and the halting of the G1 phase cell cycle in the porcine alveolar macrophage line 3D4/21. Transcriptomic analysis of DON-exposed cells showed distinct expression patterns in 3104 genes, with notable upregulation of ER stress-related genes, including IRE1, CHOP, XBP1 and JNK. Our subsequent validation via qPCR and Western blot analyses confirmed the attenuation of GRP78 and BCL-2, coupled with the upregulation of IRE1, CHOP, JNK, p-JNK, and Bax in DON-induced cells, indicating the instigation of ER stress-associated apoptosis by DON. The addition of 5 mM 4-phenylbutyric acid (4-PBA), an ER stress inhibitor, decreased levels of CHOP, IRE1, JNK, p-JNK, and Bax, while increasing levels of GRP78 and Bcl-2, suggesting that 4-PBA alleviated DON-induced ER stress and apoptosis. Overall, our findings provide new insights into DON-induced ER stress via the IRE1/JNK/CHOP pathway, leading to subsequent cellular apoptosis.

11.
Environ Sci Pollut Res Int ; 30(43): 97209-97218, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37589846

RESUMO

Algae plays a significant role for the primary production in the oligotrophic ecosystems such as the acid mine pit lakes. Graesiella sp. MA1 was a new acid-tolerant photosynthetic protist isolated from an acid mine pit lake. To understand the acid responses of Graesiella sp. MA1, its physiological changes and metabolomics were studied during long-term acid stress. Photosynthetic pigments, soluble proteins, and antioxidant systems of Graesiella sp. MA1 cells displayed two phases, the adaptation phase and the growth phase. During the adaptation phase, both photosynthetic pigments and soluble proteins were inhibited, while antioxidant activity of SOD, APX, and GSH were promoted to response to the organism's damage. Metabolomics results revealed lipids and organic acids were abundant components in Graesiella sp. MA1 cells. In response to acid stress, the levels of acid-dependent resistant amino acids, including glutamate, aspartate, arginine, proline, lysine, and histidine, accumulated continuously to maintain orderly intracellular metabolic processes. In addition, fatty acids were mainly unsaturated, which could improve the fluidity of the cell membranes under acid stress. Metabolomic and physiological changes showed that Graesiella sp. MA1 had tolerance during long-term acid stress and the potential to be used as a bioremediation strain for the acidic wastewater.


Assuntos
Clorófitas , Ecossistema , Metabolômica , Ácidos Graxos , Antioxidantes , Ácido Glutâmico
12.
Int J Mol Sci ; 24(11)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37298559

RESUMO

Estrus is crucial for cow fertility in modern dairy farms, but almost 50% of cows do not show the behavioral signs of estrus due to silent estrus and lack of suitable and high-accuracy methods to detect estrus. MiRNA and exosomes play essential roles in reproductive function and may be developed as novel biomarkers in estrus detection. Thus, we analyzed the miRNA expression patterns in milk exosomes during estrus and the effect of milk exosomes on hormone secretion in cultured bovine granulosa cells in vitro. We found that the number of exosomes and the exosome protein concentration in estrous cow milk were significantly lower than in non-estrous cow milk. Moreover, 133 differentially expressed exosomal miRNAs were identified in estrous cow milk vs. non-estrous cow milk. Functional enrichment analyses indicated that exosomal miRNAs were involved in reproduction and hormone-synthesis-related pathways, such as cholesterol metabolism, FoxO signaling pathway, Hippo signaling pathway, mTOR signaling pathway, steroid hormone biosynthesis, Wnt signaling pathway and GnRH signaling pathway. Consistent with the enrichment signaling pathways, exosomes derived from estrous and non-estrous cow milk both could promote the secretion of estradiol and progesterone in cultured bovine granulosa cells. Furthermore, genes related to hormonal synthesis (CYP19A1, CYP11A1, HSD3B1 and RUNX2) were up-regulated after exosome treatment, while exosomes inhibited the expression of StAR. Moreover, estrous and non-estrous cow-milk-derived exosomes both could increase the expression of bcl2 and decrease the expression of p53, and did not influence the expression of caspase-3. To our knowledge, this is the first study to investigate exosomal miRNA expression patterns during dairy cow estrus and the role of exosomes in hormone secretion by bovine granulosa cells. Our findings provide a theoretical basis for further investigating milk-derived exosomes and exosomal miRNA effects on ovary function and reproduction. Moreover, bovine milk exosomes may have effects on the ovaries of human consumers of pasteurized cow milk. These differential miRNAs might provide candidate biomarkers for the diagnosis of dairy cow estrus and will assist in developing new therapeutic targets for cow infertility.


Assuntos
MicroRNAs , Leite , Feminino , Animais , Bovinos , Humanos , Leite/metabolismo , MicroRNAs/metabolismo , Estro , Progesterona/metabolismo , Células da Granulosa/metabolismo
13.
Genes Genomics ; 45(6): 771-781, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37133719

RESUMO

BACKGROUND: Host factors are required for Influenza virus infection and have great potential to become antiviral target. OBJECTIVE: Here we demonstrate the role of TNK2 in influenza virus infection. CRISPR/Cas9 induced TNK2 deletion in A549 cells. METHODS: CRISPR/Cas9-mediated deletion of TNK2. Western blotting and qPCR was used to measure the expression of TNK2 and other proteins. RESULTS: CRISPR/Cas9-mediated deletion of TNK2 decreased the replication of influenza virus and significantly inhibited the ex-pression of viral proteins and TNK2 inhibitors (XMD8-87 and AIM-100) reduced the expression of influenza M2, while over-expression of TNK2 weakened the resistance of TNK2-knockout cells to influenza virus infection. Furthermore, a decrease of nuclear import of IAV in the infected TNK2 mutant cells was observed in 3 h post-infection. Interestingly, TNK2 deletion enhanced the colocalization of LC3 with autophagic receptor p62 and led to the attenuation of influenza virus-caused accumulation of autophagosomes in TNK2 mutant cells. Further, confocal microscopy visualization result showed that influenza viral matrix 2 (M2) was colocalized with Lamp1 in the infected TNK2 mutant cells in early infection, while almost no colocalization between M2 and Lamp1 was observed in IAV-infected wild-type cells. Moreover, TNK2 depletion also affected the trafficking of early endosome and the movement of influenza viral NP and M2. CONCLUSION: Our results identified TNK2 as a critical host factor for influenza viral M2 protein trafficking, suggesting that TNK2 will be an attractive target for the development of antivirals therapeutics.


Assuntos
Vírus da Influenza A , Influenza Humana , Proteínas Tirosina Quinases , Humanos , Células A549 , Vírus da Influenza A/genética , Influenza Humana/genética
14.
Genes (Basel) ; 14(4)2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-37107704

RESUMO

We assessed differentially expressed (DE) mRNAs and lncRNAs in the liver of septic pigs to explore the key factors regulating lipopolysaccharide (LPS)-induced liver injury. We identified 543 DE lncRNAs and 3642 DE mRNAs responsive to LPS. Functional enrichment analysis revealed the DE mRNAs were involved in liver metabolism and other pathways related to inflammation and apoptosis. We also found significantly upregulated endoplasmic reticulum stress (ERS)-associated genes, including the receptor protein kinase receptor-like endoplasmic reticulum kinase (PERK), the eukaryotic translation initiation factor 2α (EIF2S1), the transcription factor C/EBP homologous protein (CHOP), and activating transcription factor 4 (ATF4). In addition, we predicted 247 differentially expressed target genes (DETG) of DE lncRNAs. The analysis of protein-protein interactions (PPI) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway detected key DETGs that are involved in metabolic pathways, such as N-Acetylgalactosaminyltransferase 2 (GALNT2), argininosuccinate synthetase 1 (ASS1), and fructose 1,6-bisphosphatase 1 (FBP1). LNC_003307 was the most abundant DE lncRNA in the pig liver, with a marked upregulation of >10-fold after LPS stimulation. We identified three transcripts for this gene using the rapid amplification of the cDNA ends (RACE) technique and obtained the shortest transcript sequence. This gene likely derives from the nicotinamide N-methyltransferase (NNMT) gene in pigs. According to the identified DETGs of LNC_003307, we hypothesize that this gene regulates inflammation and endoplasmic reticulum stress in LPS-induced liver damage in pigs. This study provides a transcriptomic reference for further understanding of the regulatory mechanisms underlying septic hepatic injury.


Assuntos
RNA Longo não Codificante , Animais , Suínos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Lipopolissacarídeos/toxicidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fígado/metabolismo , Inflamação/metabolismo
15.
Waste Manag ; 159: 125-133, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36753855

RESUMO

Pyrolysis can realize the reduction and resource utilization of municipal sewage sludge (MSS). In this paper, a self-sustaining pyrolysis process is designed for municipal sewage sludge, and the process flow is simulated by Aspen plus software. By changing the initial moisture content of sludge, moisture content after drying, pyrolysis temperature and air supply in the incinerator, the possibility of achieving energy self-balance in the system is analysed. The simulation results show that by adjusting the parameters of the system, this process can realize the energy self-balance of sludge drying and pyrolysis treatment. Considering the system's energy loss, the dry basis calorific value of sludge should not be less than 10 MJ/kg. The higher the initial moisture content of sludge, the more external energy input the system needs. It is recommended to dehydrate sludge mechanically to about 60 % before entering the system. When the pyrolysis temperature is increased, the amount of oil and gas produced by sludge pyrolysis increases, and it is easier to achieve self-balance of system energy. But the higher the pyrolysis temperature, the greater the energy consumption required. In practice, it is suggested that the pyrolysis temperature is about 400 °C. The moisture content of dried sludge has little effect on the energy self-balance of the system, and it is recommended to be about 30 %. The air supply volume of the incinerator mainly affects the flue gas outlet temperature and flue gas volume, but has little effect on the energy balance of the system.


Assuntos
Temperatura Alta , Esgotos , Pirólise , Temperatura , Incineração
16.
J Org Chem ; 88(4): 2599-2604, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36701645

RESUMO

Chemo- and site-selective functionalization of phenols offers a rapid strategy for the synthesis of phenol derivatives with diverse structures. Herein, we report a Pd-catalyzed regioselective C-H bond allylic alkylation of phenols with 1,3-dienes, which has precision reactivity at the ortho C-H bond of 2-naphthols, 1-naphthols, and electron-rich phenols. The reaction is accelerated by a diphosphine ligand, does not need any other additive, and features broad substrate scope and good chemo- and regioselectivity. In addition, we have also investigated the asymmetric variant, and the product could be achieved in up to 55% ee.

17.
Bioprocess Biosyst Eng ; 46(4): 577-588, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36580135

RESUMO

The main objective of the current study is to fabricate a 3D scaffold using alginate hydrogel implemented with carbon nanoparticles (CNPs) as the filler. The SEM imaging revealed that the scaffold possesses a porous internal structure with interconnected pores. The swelling value of the scaffolds (more than 400%) provides a wet niche for bone cell proliferation and migration. The in vitro evaluations showed that the scaffolds were hemocompatible (with hemolysis induction lower than 5%) and cytocompatible (inducing significant proliferative effect (cell viability of 121 ± 4%, p < 0.05) for AlG/CNPs 10%). The in vivo studies showed that the implantation of the fabricated 3D nanocomposite scaffolds induced a bone-forming effect and mediated bone formation into the induced bone defect. In conclusion, these results implied that the fabricated NFC-integrated 3D scaffold exhibited promising characteristics beneficial for bone regeneration and can be applied as the bone tissue engineering scaffold.


Assuntos
Nanocompostos , Nanopartículas , Hidrogéis/química , Alicerces Teciduais/química , Engenharia Tecidual/métodos , Nanocompostos/química , Carbono
18.
Pharmaceutics ; 14(11)2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36365160

RESUMO

The clinical translation of therapeutic peptides is generally challenged by multiple issues involving absorption, distribution, metabolism and excretion. In this study, a macrophage membrane-coated poly(lactic-co-glycolic acid) (PLGA) nanodelivery system was developed to enhance the bioavailability of the somatostatin (SST) peptide, which faces the hurdles of short half-life and potential side effects in the treatment of chronic pancreatitis. Using a facile nanoprecipitation strategy, SST was loaded in the nanoparticles with an encapsulation efficiency (EE) and a loading efficiency (LE) of 73.68 ± 3.56% and 1.47 ± 0.07%, respectively. The final formulation of SST-loaded nanoparticles with the camouflage of macrophage membrane (MP-SST) showed a mean diameter of 151 ± 4 nm and an average zeta potential of −29.6 ± 0.3 mV, which were stable long term during storage. With an above 90% cell viability, a hemolysis level of about 2% (<5%) and a preference for being ingested by activated endothelial cells compared to macrophages, the membrane−polymer hybrid nanoparticle showed biocompatibility and targeting capability in vitro. After being intravenously administered to mice with chronic pancreatitis, the MP-SST increased the content of SST in the serum (123.6 ± 13.6 pg/mL) and pancreas (1144.9 ± 206.2 pg/g) compared to the treatment of (Dulbecco's phosphate-buffered saline) DPBS (61.7 ± 6.0 pg/mL in serum and 740.2 ± 172.4 pg/g in the pancreas). The recovery of SST by MP-SST downregulated the expressions of chronic pancreatitis-related factors and alleviated the histologic severity of the pancreas to the greatest extent compared to other treatment groups. This augmentation of SST therapeutic effects demonstrated the superiority of integrating the synthetic polymer with biological membranes in the design of nanoplatforms for advanced and smart peptide delivery. Other peptides like SST can also be delivered via the membrane−polymer hybrid nanosystem for the treatment of diseases, broadening and promoting the potential clinical applications of peptides as therapeutics.

19.
Polymers (Basel) ; 14(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36365702

RESUMO

In air and railway transportation, corrosion and wear lead to the rapid failure of equipment. Epoxy (EP)-based coatings are widely used in research on the anti-corrosion of organic coatings, but their application as materials for wear resistance is limited due to their non-abrasive properties. In this study, a novel high-performance epoxy-based composite coating was developed through the self-assembly of silicon carbide (SiC) and graphene oxide (GO) and the tuning of the interfacial structure with epoxy resin. The coatings were comprehensively characterized, including their electrochemical behavior, a salt spray test, and friction and wear experiments, and the optimal addition ratio of SiC-G@GO (SiC-G@GO was prepared by the self-assembly of γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH560)-modified SiC (SiC-G) on the surface of GO sheets) in the epoxy coatings was explored. Benefiting from the labyrinth effect and their rolling-friction-like microstructure, the 1 wt% SiC-G@GO/EP coating exhibits excellent wear and corrosion resistance. Compared with pure epoxy resin, the 1 wt% SiC-G@GO/EP coating increased by 4 orders of magnitude after 10 days of immersion. The average friction coefficient was 41.5% lower than that of the pure EP coating, and the wear rate was 56.6% lower. This research has positive implications for the development and application of anti-corrosion and wear-resistant organic coatings.

20.
ACS Omega ; 7(38): 34563-34572, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36188289

RESUMO

Oxygen-containing alternative fuels have excellent potential to improve diesel fuel economy and reduce particulate matter (PM) emissions. In this study, a novel mixed dialkyl oxalate (mDAO) as an additive was applied to substitute conventional diesel to investigate the effects of mDAO on the combustion and emission characteristics of a high-pressure common-rail diesel engine. The research conducted suggested that the peak pressure rise rate in the main injection stage and the peak in-cylinder pressure presented the rising tendency with the increased mass fraction of mDAO at most test conditions. With the addition of mDAO, the in-cylinder temperature (T) and brake thermal efficiency (BTE) were higher than that of pure diesel. When the mass fraction of mDAO in the mDAO/diesel blend was 30%, the improvement of BTE was most obvious. The ignition delay was prolonged as the mass fraction of mDAO was increased due to the lower cetane number of the mDAO. In addition, adding mDAO into diesel had an effective impact on the reduction of PM emissions, while the nitrogen oxide (NO x ) emissions deteriorated. These results indicate that mDAO is a great potential diesel alternative fuel.

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