RÉSUMÉ
Acrylic pressure sensitive adhesives, modified by polyurethane (PU), achieve selective optimization through the designability of polyurethanes. In this paper, PU macromonomers were prepared by a two-step synthesis method, using polypropylene glycol or polyethylene glycol with different molecular weights as soft segments and different types of diisocyanates: isophorone diisocyanate, hexamethylene diisocyanate, dicyclohexylmethylmethane diisocyanate (HMDI), 2,4-toluene diisocyanate (TDI), and 4,4'-diphenylmethane diisocyanate (MDI) and chain extenders as hard segments. After being terminated by capping agents, a series of PU macromonomers of different molecular weights and structures were obtained and used to modify the acrylic base adhesives. Compared to unmodified adhesives, acrylic adhesives modified by PU macromonomers have improved adhesion performances and heat resistance and show an increasing trend with the increase of molecular weight of diols. Diols with a molecular weight of 600 have the best effect. Diisocyanates containing benzene rings can better improve the thermal performance of adhesives, where P MDI containing a biphenyl ring is the best, while aliphatic isocyanate groups have a greater improvement in adhesion performance, and the adhesion performance of P HDI with a long carbon chain is the best.
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Fusarium head blight caused by Fusarium graminearum is a significant pathogen affecting wheat crops. During the infection process, effector proteins are secreted to modulate plant immunity and promote infection. The toxin deoxynivalenol is produced in infected wheat grains, posing a threat to human and animal health. Serine carboxypeptidases (SCPs) belong to the α/ß hydrolase family of proteases and are widely distributed in plant and fungal vacuoles, as well as animal lysosomes. Research on SCPs mainly focuses on the isolation, purification, and production of a small number of fungi. The role of SCPs in plant secretion, growth and development, and stress resistance has also been extensively studied. However, their functions in F. graminearum, a fungal pathogen, remain relatively unknown. In this study, the biological functions of the FgSCP gene in F. graminearum were investigated. The study revealed that mutations in FgSCP affected the nutritional growth, sexual reproduction, and stress tolerance of F. graminearum. Furthermore, the deletion of FgSCP resulted in reduced pathogenicity and hindered the biosynthesis of deoxynivalenol. The upregulation of FgSCP expression 3 days after infection indicated its involvement in host invasion, possibly acting as a "smokescreen" to deceive the host and suppress the expression of host defensive genes. Subsequently, we confirmed the secretion ability of FgSCP and its ability to inhibit the cell death induced by INF1 in Nicotiana benthamiana cells, indicating its potential role as an effector protein in suppressing plant immune responses and promoting infection. In summary, we have identified FgSCP as an essential effector protein in F. graminearum, playing critical roles in growth, virulence, secondary metabolism, and host invasion.
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Low back pain (LBP) may profoundly impact the quality of life across the globe, and intervertebral disc degeneration (IVDD) is the major cause of LBP; however, targeted pharmaceutical interventions for IVDD are still lacking. Ferroptosis is a novel form of iron-dependent programmed cell death. Studies have showed that ferroptosis may closely associate with IVDD; thus, targeting ferroptosis may have great potential for IVDD therapy. Non-steroidal anti-inflammatory drugs (NSAIDs) are the first-line medications for LBP, while nuclear factor-erythroid 2-related factor-2 (Nrf2) is a key inhibitory protein for ferroptosis. In the current study, we conducted a molecular docking screening between NSAIDs library and Nrf2 protein. Tinoridine was shown to have a high binding affinity to Nrf2. The in vitro study in nucleus pulposus (NP) cells showed that Tinoridine may promote the expression and activity of Nrf2, it may also rescue RSL3-induced ferroptosis in NP cells. Knockdown of Nrf2 reverses the protective effect of Tinoridine on RSL3-induced ferroptosis in NP cells, suggesting that the inhibitory effect of Tinoridine on ferroptosis is through Nrf2. In vivo study demonstrated that Tinoridine may attenuate the progression of IVDD in rats. As NSAIDs are already clinically used for LBP therapy, the current study supports Tinoridine's application from the view of ferroptosis inhibition.
Sujet(s)
Anti-inflammatoires non stéroïdiens , Ferroptose , Dégénérescence de disque intervertébral , Facteur-2 apparenté à NF-E2 , Ferroptose/effets des médicaments et des substances chimiques , Animaux , Dégénérescence de disque intervertébral/traitement médicamenteux , Dégénérescence de disque intervertébral/anatomopathologie , Dégénérescence de disque intervertébral/métabolisme , Rats , Facteur-2 apparenté à NF-E2/métabolisme , Facteur-2 apparenté à NF-E2/génétique , Anti-inflammatoires non stéroïdiens/pharmacologie , Humains , Nucleus pulposus/effets des médicaments et des substances chimiques , Nucleus pulposus/métabolisme , Nucleus pulposus/anatomopathologie , Simulation de docking moléculaire , Mâle , Rat Sprague-Dawley , Lombalgie/traitement médicamenteux , Lombalgie/anatomopathologieRÉSUMÉ
Injectable hydrogels based on biopolymers, fabricated utilizing diverse chemical and physical methodologies, exhibit exceptional physical, chemical, and biological properties. They have multifaceted applications encompassing wound healing, tissue regeneration, and across diverse scientific realms. This review critically evaluates their largely uncharted potential in ophthalmology, elucidating their diverse applications across an array of ocular diseases. These conditions include glaucoma, cataracts, corneal disorders (spanning from age-related degeneration to trauma, infections, and underlying chronic illnesses), retina-associated ailments (such as diabetic retinopathy, retinitis pigmentosa, and age-related macular degeneration (AMD)), eyelid abnormalities, and uveal melanoma (UM). This study provides a thorough analysis of applications of injectable hydrogels based on biopolymers across these ocular disorders. Injectable hydrogels based on biopolymers can be customized to have specific physical, chemical, and biological properties that make them suitable as drug delivery vehicles, tissue scaffolds, and sealants in the eye. For example, they can be engineered to have optimum viscosity to be injected intravitreally and sustain drug release to treat retinal diseases. Their porous structure and biocompatibility promote cellular infiltration to regenerate diseased corneal tissue. By accentuating their indispensable role in ocular disease treatment, this review strives to present innovative and targeted approaches in this domain, thereby advancing ocular therapeutics.
Sujet(s)
Maladies de l'oeil , Hydrogels , Hydrogels/composition chimique , Humains , Biopolymères/composition chimique , Maladies de l'oeil/traitement médicamenteux , Animaux , Systèmes de délivrance de médicaments , Injections , Matériaux biocompatibles/composition chimiqueRÉSUMÉ
The delivery of intravenously administered cancer therapeutics to brain tumors is limited by the blood-brain barrier. A method to directly image the accumulation and distribution of macromolecules in brain tumors in vivo would greatly enhance our ability to understand and optimize drug delivery in preclinical models. This protocol describes a method for real-time in vivo tracking of intravenously administered fluorescent-labeled nanoparticles with two-photon intravital microscopy (2P-IVM) in a mouse model of glioblastoma (GBM). The protocol contains a multi-step description of the procedure, including anesthesia and analgesia of experimental animals, creating a cranial window, GBM cell implantation, placing a head bar, conducting 2P-IVM studies, and post-surgical care for long-term follow-up studies. We show representative 2P-IVM imaging sessions and image analysis, examine the advantages and disadvantages of this technology, and discuss potential applications. This method can be easily modified and adapted for different research questions in the field of in vivo preclinical brain imaging.
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Tumeurs du cerveau , Glioblastome , Animaux , Souris , Glioblastome/imagerie diagnostique , Modèles animaux de maladie humaine , Encéphale , Tumeurs du cerveau/imagerie diagnostique , Microscopie intravitaleRÉSUMÉ
Water-based evaporative cooling is emerging as a promising technology to provide sustainable and low-cost cold to alleviate the rising global cooling demand. Given the significant and fast progress made in recent years, this review aims to provide a timely overview on the state-of-the-art material design and engineering in water-based evaporative cooling. The fundamental mechanisms and major components of three water-based evaporative cooling processes are introduced, including direct evaporative cooling, cyclic sorption-driven liquid water evaporative cooling (CSD-LWEC), and atmospheric water harvesting-based evaporative cooling (AWH-EC). The distinctive requirements on the sorbent materials in CSD-LWEC and AWH-EC are highlighted, which helps synthesize the literature information on the advanced material design and engineering for the purpose of improving cooling performance. The challenges and future outlooks on further improving the water-based evaporative cooling performance are also provided.
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Perovskite solar cells (PSCs) are promising candidates for next-generation photovoltaics owing to their unparalleled power conversion efficiencies (PCEs). Currently, approaches to further improve device efficiencies tend to focus on the passivation of interfacial defects. Although various strategies have been developed to mitigate these defects, many involve complex and time-consuming post-treatment processes, thereby hindering their widespread adoption in commercial applications. In this work, a concise but efficient in situ dual-interface passivation strategy is developed wherein 1-butyl-3-methylimidazolium methanesulfonate (MS) is employed as a precursor additive. During perovskite crystallization, MS can either be enriched downward through precipitation with SnO2 , or can be aggregated upward through lattice extrusion. These self-assembled MS species play a significant role in passivating the defect interfaces, thereby reducing nonradiative recombination losses, and promoting more efficient charge extraction. As a result, a PCE >25% (certified PCE of 24.84%) is achieved with substantially improved long-term storage and photothermal stabilities. This strategy provides valuable insights into interfacial passivation and holds promise for the industrialization of PSCs.
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Approaches for rapidly identifying patients at high risk of early breast cancer recurrence are needed. Image-based methods for prescreening hematoxylin and eosin (H&E) stained tumor slides could offer temporal and financial efficiency. We evaluated a data set of 704 1-mm tumor core H&E images (2-4 cores per case), corresponding to 202 participants (101 who recurred; 101 non-recurrent matched on age and follow-up time) from breast cancers diagnosed between 2008-2012 in the Carolina Breast Cancer Study. We leveraged deep learning to extract image information and trained a model to identify recurrence. Cross-validation accuracy for predicting recurrence was 62.4% [95% CI: 55.7, 69.1], similar to grade (65.8% [95% CI: 59.3, 72.3]) and ER status (66.3% [95% CI: 59.8, 72.8]). Interestingly, 70% (19/27) of early-recurrent low-intermediate grade tumors were identified by our image model. Relative to existing markers, image-based analyses provide complementary information for predicting early recurrence.
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Dark-field microscopy offers several advantages, including high image contrast, minimal cell damage, and the absence of photobleaching of nanoprobes, which make it highly advantageous for cell imaging. The NIR-II window has emerged as a prominent research focus in optical imaging in recent years, with its low autofluorescence background in biological samples and high imaging SBR. In this study, we initially compared dark-field imaging results of colorectal cancer cells in both visible and NIR-II wavelengths, confirming the superior performance of NIR-II imaging. Subsequently, we synthesized gold nanorods with localized surface plasmon resonance (LSPR) absorption peaks in the NIR-II window. After bio-compatible modification, we non-specifically labeled colorectal cancer cells for NIR-II dark-field scattering imaging. The imaging results revealed a sixfold increase in SBR, especially in the 1425-1475 nm wavelength range. Finally, we applied this imaging system to perform dark-field imaging of cell nuclei in the NIR-II region and used GNRs for specific nuclear labeling in colorectal cancer cells. The resulting images exhibited higher SBR than non-specifically-labeled cell imaging, and the probe's labeling was precise, confirming the potential application of this system in photothermal therapy and drug delivery for cancer cells.
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Protein disulfide isomerase (PDI) is a member of the thioredoxin (Trx) superfamily with important functions in cellular stability, ion uptake, and cellular differentiation. While PDI has been extensively studied in humans and animals, its role in fungi remains relatively unknown. In this study, the biological functions of FgEps1, a disulfide bond isomerase in the fungal pathogen Fusarium graminearum, were investigated. It was found that FgEps1 mutation affected nutritional growth, asexual and sexual reproduction, and stress tolerance. Additionally, its deletion resulted in reduced pathogenicity and impaired DON toxin biosynthesis. The involvement of FgEps1 in host infection was also confirmed, as its expression was detected during the infection period. Further investigation using a yeast signal peptide secretion system and transient expression in Nicotiana benthamiana showed that FgEps1 suppressed the immune response of plants and promoted infection. These findings suggest that virulence factor FgEps1 plays a crucial role in growth, development, virulence, secondary metabolism, and host infection in F. graminearum.
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Sediment heavy metal contamination poses substantial risks to microbial community composition and functional gene distribution. Bohai Bay (BHB), the second-largest bay in the Bohai Sea, is subject to severe anthropogenic pollution. However, to date, there have been no studies conducted to evaluate the distribution of metal resistance genes (MRGs) and bacterial communities in the coastal sediments of BHB. In this study, we employed high-throughput sequencing based on 16S rRNA genes and real-time quantitative PCR (qPCR) to provide a comprehensive view of toxic metals, MRGs, and bacterial communities in BHB's coastal sediment samples across two seasons. We detected high levels of Cd in the summer samples and As in the autumn samples. The metal content in most autumn samples and all summer samples, based on ecological indices, indicated low ecological risk. Proteobacteria dominated all samples, followed by Desulfobacterota, Bacteroidota and Campilobacterota. Bacterial community variability was higher between autumn sampling sites but more stable in summer. We detected 9 MRG subtypes in all samples, with abundances ranging from 4.58 × 10-1 to 2.25 copies/16S rRNA copies. arsB exhibited the highest relative abundance, followed by acr3, czcA and arrA. The efflux mechanism is a common mechanism for sediment resistance to metal stress in Bohai Bay. Procrustes analysis indicated that bacterial community composition may be a determinant of MRGs composition in BHB sediments. Network analysis suggested that eight classes could be potential hosts for six MRGs. However, this type of correlation requires further validation. To summarize, our study offers preliminary insights into bacterial community and MRG distribution patterns in heavy metal-exposed sediments, laying the groundwork for understanding microbial community adaptations in multi-metal polluted environments and supporting ecological restoration efforts.
Sujet(s)
Métaux lourds , Polluants chimiques de l'eau , Sédiments géologiques , Baies (géographie) , ARN ribosomique 16S/génétique , Polluants chimiques de l'eau/toxicité , Polluants chimiques de l'eau/analyse , Surveillance de l'environnement , Bactéries/génétique , Métaux lourds/toxicité , Métaux lourds/analyse , Chine , Gènes bactériensRÉSUMÉ
We report for the first time that Pd nanocrystals can absorb H via a "single-phase pathway" when particles with a proper combination of shape and size are used. Specifically, when Pd icosahedral nanocrystals of 7- and 12-nm in size are exposed to H atoms, the H-saturated twin boundaries can divide each particle into 20 smaller single-crystal units in which the formation of phase boundaries is no longer favored. As such, absorption of H atoms is dominated by the single-phase pathway and one can readily obtain PdHx with anyx in the range of 0-0.7. When switched to Pd octahedral nanocrystals, the single-phase pathway is only observed for particles of 7â nm in size. We also establish that the H-absorption kinetics will be accelerated if there is a tensile strain in the nanocrystals due to the increase in lattice spacing. Besides the unique H-absorption behaviors, the PdHx (x=0-0.7) icosahedral nanocrystals show remarkable thermal and catalytic stability toward the formic acid oxidation due tothe decrease in chemical potential for H atoms in a Pd lattice under tensile strain.
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With mastery over the colloidal synthesis of monometallic nanocrystals, a combination of two distinct metals with intricate architectures has emerged as a new direction of innovation. Among the diverse architectures, the one with a core-shell structure has attracted the most scientific endeavors owing to its merits of high controllability and variability. Along with the new hopes arising from the addition of a shell composed of a different metal, there comes unexpected complications for the surface composition, hindering both structural understanding and application performance. In this Focus article, we present a brief overview of the opportunities provided by the bimetallic core-shell nanocrystals, followed by a discussion of the technical challenge to elucidate the true composition of the outermost surface. Some of the promising solutions are then highlighted as well, aiming to inspire future efforts toward this frontier of research.
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The impacts of eutrophication on benthic ecological functions are of increasing concern in recent years. In order to assess the response of macrobenthic fauna to increasing eutrophication, two field sampling surveys were conducted during the summer (July-August 2020) and autumn (October-November 2020) from offshore, nearshore to estuarine sediments in Bohai Bay, northern China. Biological trait analysis was employed for the assessment of macrofaunal samples. The results indicated that there was an increase in the proportion of benthic burrowering or tube-dwelling sediment feeders and taxa with higher larval dispersal ability, but a decrease in the proportion of taxa showing high motility in areas with higher nutrient levels. Seasonal differences were also noted in the shift in biological traits, with a significantly lower similarity among the sampling areas in summer and a higher proportion of carnivorous taxa in autumn. The findings suggested that long-term disturbance can lead to the dominance of smaller body-sized benthic species and reduced sediment quality, impeding ecological recovery of benthic organisms under such harsh environment.
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Baies (géographie) , Écosystème , Surveillance de l'environnement , Chine , Eutrophisation , Sédiments géologiques/analyseRÉSUMÉ
Background: Phage display technology has been established as a powerful screening approach to select ligands or peptides for binding to proteins. Despite rapid growth in the field, there has been a relative dearth of quantitative criteria to measure the effectiveness of the process of phage display screening. Since human serum albumin (HSA) has been extensively studied as a drug carrier to extend the plasma half-life of protein therapeutics, the use of phage display technology is required for identifying albumin-binding peptides as the very promising strategy of albumin-binding against albumin fusion. The construction of albumin-binding drug requires the assessment of a large quantity of HSA-binding peptide (HSA binder) candidates for conjugation with therapeutic proteins. The use of the linear epitope mapping method has allowed researchers to discover many HSA-binding peptides. However, it may be inefficient to select these peptides based on sequence identity via randomly sequencing individual phage clones from enrichment pools. Method: Here, a simple assessment method to facilitate phage display selection of HSA-binding peptides was recommended. With experimentally determined phage titer, one can calculate the specificity ratios, the recovery yields and the relative dissociation constants, which are defined as quantitative criteria for panning and characterization of the binding phage fused peptides. Results: Consequently, this approach may not only enable more rapid and low-cost phage display screening, but also efficiently reduce pseudo-positive phages selected as HSA binders for conjugation with therapeutic proteins.
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Bactériophages , Banque de peptides , Humains , Peptides/génétique , Techniques d'exposition à la surface cellulaire , Albumines/métabolisme , Bactériophages/génétique , Sérum-albumine humaine/métabolismeRÉSUMÉ
Effects of Orientin on murine chondrocytes treated with interleukin-1ß (IL-1ß) were evaluated using qPCR, western blot analysis, ELISA, and immunofluorescent staining in vitro. In vivo, We established a standard OA model by performing the destabilized medial meniscus (DMM) surgery on C57BL/6 mice, and assessed healing effect of Orientin by X-ray imaging, histopathological analysis, immunohistochemical staining. Osteoarthritis (OA) is the most common form of degenerative joint disease in clinic and the chondrocyte inflammation plays the most important role in OA development. The natural flavonoid compound (Orientin) has anti-inflammatory bioactive properties in the treatment of various diseases. But studies have not explored whether Orientin modulates OA progression. In this study, a significant suppression in IL-1ß-mediated pro-inflammatory mediators and the degradation of cartilage extracellular matrix (ECM) was observed in vitro through qPCR, western blot analysis, ELISA, and immunofluorescent staining after the treatment with Orientin. In addition, Orientin abrogated DMM surgery induced cartilage degradation in mice, which was assessed by X-ray imaging, histopathological analysis, immunohistochemical staining. Mechanistic studies showed that Orientin suppressed OA development by downregulating activation of NF-κB by activating Nrf2/HO-1 axis and SIRT6 signaling pathway. These results provide evidence that Orientin serves as a potentially viable compound for the treatment of OA.
Sujet(s)
Arthrose , Sirtuines , Souris , Animaux , Chondrocytes/métabolisme , Facteur de transcription NF-kappa B/métabolisme , Facteur-2 apparenté à NF-E2/métabolisme , Facteur-2 apparenté à NF-E2/pharmacologie , Arthrose/métabolisme , Souris de lignée C57BL , Inflammation/traitement médicamenteux , Inflammation/métabolisme , Flavonoïdes/pharmacologie , Flavonoïdes/usage thérapeutique , Ménisques de l'articulation du genou/anatomopathologie , Sirtuines/métabolisme , Sirtuines/pharmacologie , Interleukine-1 bêta/métabolisme , Cellules cultivéesRÉSUMÉ
In E. coli and related species, flagellar brake protein YcgR responds to the elevated intracellular c-di-GMP, decreases the flagellar rotation speed, causes a CCW rotation bias, and regulates bacterial swimming. Boehm et al. suggested that c-di-GMP-activated YcgR directly interacted with the motor protein MotA to curb flagellar motor output. Paul et al. proposed that YcgR disrupted the organization of the FliG C-terminal domain to bias the flagellar rotation. The target proteins are controversial, and the role of motor proteins remains unclear in flagellar rotation speed and direction regulation by YcgR. Here we assayed the motor proteins' affinity via a modified FRET biosensor and accessed the role of those key residue via bead assays. We found that YcgR could interact with both MotA and FliG, and the affinities could be enhanced upon c-di-GMP binding. Furthermore, residue D54 of YcgR-N was needed for FliG binding. The mutation of the FliG binding residue D54 or the MotA binding ones, F117 and E232, restored flagellar rotation speed in wild-type cells and cells lacking chemotaxis response regulator CheY that switched the flagellar rotation direction and decreased the CCW ratio in wild-type cells. We propose that c-di-GMP-activated YcgR regulated the flagellar rotation speed and direction via its interaction with motor proteins MotA and FliG. Our work suggest the role of YcgR-motor proteins interaction in bacterial swimming regulation.
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Macrophages are highly heterogeneous and exhibit a diversity of functions and phenotypes. They can be divided into pro-inflammatory macrophages (M1) and anti-inflammatory macrophages (M2). Diabetic wounds are characterized by a prolonged inflammatory phase and difficulty in healing due to the accumulation of pro-inflammatory (M1) macrophages in the wound. Therefore, hydrogel dressings with macrophage heterogeneity regulation function hold great promise in promoting diabetic wound healing in clinical applications. However, the precise conversion of pro-inflammatory M1 to anti-inflammatory M2 macrophages by simple and biosafe approaches is still a great challenge. Here, an all-natural hydrogel with the ability to regulate macrophage heterogeneity is developed to promote angiogenesis and diabetic wound healing. The protocatechuic aldehyde hybridized collagen-based all-natural hydrogel exhibits good bioadhesive and antibacterial properties as well as reactive oxygen species scavenging ability. More importantly, the hydrogel is able to convert M1 macrophages into M2 macrophages without the need for any additional ingredients or external intervention. This simple and safe immunomodulatory approach shows great application potential for shortening the inflammatory phase of diabetic wound repair and accelerating wound healing.
Sujet(s)
Diabète , Hydrogels , Humains , Cicatrisation de plaie/physiologie , Macrophages , PhénotypeRÉSUMÉ
Stereotactic neurosurgery has been employed in autism spectrum disorders (ASD). However, its safety and effectiveness remain unclear owing to limited sample size and other methodological limitations. We aimed to systematically investigate the safety and efficacy of stereotactic neurosurgery for ASD. Eleven studies with 36 patients were included. Stereotactic neurosurgery alleviated the obsessive-compulsive disorder and aggressive behavior symptoms in ASD, with a mean improvement of 42.74% and 59.59% in the Yale-Brown Obsessive Compulsive Scale and Overt Aggression Scale scores, respectively. Systematic studies are necessary to explore the role of deep brain stimulation for social and communication difficulties in ASD.