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1.
Front Immunol ; 15: 1411490, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39139570

RESUMEN

Immunotherapy has revolutionized cancer treatment by leveraging the immune system's innate capabilities to combat malignancies. Despite the promise of tumor antigens in stimulating anti-tumor immune responses, their clinical utility is hampered by limitations in eliciting robust and durable immune reactions, exacerbated by tumor heterogeneity and immune evasion mechanisms. Recent insights into the immunogenic properties of host homologous microbial antigens have sparked interest in their potential for augmenting anti-tumor immunity while minimizing off-target effects. This review explores the therapeutic potential of microbial antigen peptides in tumor immunotherapy, beginning with an overview of tumor antigens and their challenges in clinical translation. We further explore the intricate relationship between microorganisms and tumor development, elucidating the concept of molecular mimicry and its implications for immune recognition of tumor-associated antigens. Finally, we discuss methodologies for identifying and characterizing microbial antigen peptides, highlighting their immunogenicity and prospects for therapeutic application.


Asunto(s)
Antígenos Bacterianos , Antígenos de Neoplasias , Inmunoterapia , Neoplasias , Humanos , Antígenos de Neoplasias/inmunología , Neoplasias/inmunología , Neoplasias/terapia , Inmunoterapia/métodos , Animales , Antígenos Bacterianos/inmunología , Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/uso terapéutico , Imitación Molecular/inmunología
2.
Small ; : e2403303, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-39031810

RESUMEN

Lubricating hydrogel coatings on inert rubber and plastic surfaces significantly reduce friction and wear, thus enhancing material durability and lifespan. However, achieving optimal hydration lubrication typically requires a porous polymer network, which unfortunately reduces their mechanical strength and limits their applicability where robust durability and wear-resistance are essential. In the research, a hydrogel coating with remarkable wear resistance and surface stability is developed by forming a semi-interpenetrating polymer network with polymer substrate at the interface. By employing a good solvent swelling method, monomers, and photoinitiators are embedded within the substrates' subsurface, followed by in situ polymerization under ultraviolet light, creating a robust semi-interpenetrating and entangled network structure. This approach, offering a thicker energy-dissipating layer, outperforms traditional surface modifications in wear resistance while preserving anti-fatigue, hydrophilicity, oleophobicity, and other properties. Adaptable to various rubber and plastic substrates by using suitable solvents, this method provides an efficient solution for creating durable, lubricating surfaces, broadening the potential applications in multiple industries.

3.
Mar Pollut Bull ; 205: 116546, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38870575

RESUMEN

Paralytic shellfish toxins (PSTs) can pose a serious threat to human health. Among them, saxitoxin (STX) is one of the most potent natural neurotoxins. Here, the copepod Tigriopus japonicus, was exposed to environmentally relevant concentrations (2.5 and 25 µg/L) STX for 48 h. Although no lethal effects were observed at both concentrations, the transcriptome was significantly altered, and displayed a concentration-dependent response. STX exposure decreased the copepod's metabolism and compromised immune defense and detoxification. Additionally, STX disturbed signal transduction, which might affect other cellular processes. STX exposure could inhibit the copepod's chitin metabolism, disrupting its molting process. Also, the processes related to damage repair and protection were up-regulated to fight against high concentration exposure. Collectively, this study has provided an early warning of PSTs for coastal ecosystem not only because of their potent toxicity effect but also their bioaccumulation that can transfer up the food chain after ingestion by copepods.


Asunto(s)
Copépodos , Saxitoxina , Transcriptoma , Contaminantes Químicos del Agua , Copépodos/efectos de los fármacos , Animales , Saxitoxina/toxicidad , Transcriptoma/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad
4.
J Hazard Mater ; 474: 134789, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38843636

RESUMEN

Despite the great interest in the consequences of global change stressors on marine organisms, their interactive effects on cadmium (Cd) bioaccumulation/biotoxicity are very poorly explored, particularly in combination with the toxicokinetic model and molecular mechanism. According to the projections for 2100, this study investigated the impact of elevated pCO2 and increased temperature (isolated or joint) on Cd uptake dynamics and transcriptomic response in the marine copepod Tigriopus japonicus. Toxicokinetic results showed significantly higher Cd uptake in copepods under increased temperature and its combination with elevated pCO2 relative to the ambient condition, linking to enhanced Cd bioaccumulation. Transcriptome analysis revealed that, under increased temperature and its combination with elevated pCO2, up-regulated expression of Cd uptake-related genes but down-regulation of Cd exclusion-related genes might cause increased cellular Cd level, which not only activated detoxification and stress response but also induced oxidative stress and concomitant apoptosis, demonstrating aggravated Cd biotoxicity. However, these were less pronouncedly affected by elevated pCO2 exposure. Therefore, temperature seems to be a primary factor in increasing Cd accumulation and its toxicity in the future ocean. Our findings suggest that we should refocus the interactive effects between climate change stressors and Cd pollution, especially considering temperature as a dominant driver.


Asunto(s)
Cadmio , Copépodos , Contaminantes Químicos del Agua , Cadmio/toxicidad , Cadmio/farmacocinética , Animales , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/farmacocinética , Copépodos/efectos de los fármacos , Copépodos/metabolismo , Copépodos/genética , Dióxido de Carbono/toxicidad , Dióxido de Carbono/metabolismo , Toxicocinética , Transcriptoma/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Cambio Climático , Temperatura , Calor
5.
Adv Sci (Weinh) ; : e2401000, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38884361

RESUMEN

Natural cartilage exhibits superior lubricity as well as an ultra-long service lifetime, which is related to its surface hydration, load-bearing, and deformation recovery feature. Until now, it is of great challenge to develop reliable cartilage lubricating materials or coatings with persistent robustness. Inspired by the unique biochemical structure and mechanics of natural cartilage, the study reports a novel cartilage-hydrogel composed of top composite lubrication layer and bottom mechanical load-bearing layer, by covalently manufacturing thick polyelectrolyte brush phase through sub-surface of tough hydrogel matrix with multi-level crystallization phase. Due to multiple network dissipation mechanisms of matrix, this hydrogel can achieve a high compression modulus of 11.8 MPa, a reversible creep recovery (creep strain: ≈2%), along with excellent anti-swelling feature in physiological medium (v/v0 < 5%). Using low-viscosity PBS as lubricant, this hydrogel demonstrates persistent lubricity (average COF: ≈0.027) under a high contact pressure of 2.06 MPa with encountering 100k reciprocating sliding cycles, negligible wear and a deformation recovery of collapse pit in testing area. The extraordinary lubrication performance of this hydrogel is comparable to but beyond the natural animal cartilage, and can be used as compliant coating for implantable articular material of UHMWPE to present, offering more robust lubricity than current commercial system.

6.
Gut Microbes ; 16(1): 2320283, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38444395

RESUMEN

Chronic obstructive pulmonary disease (COPD), a condition primarily linked to oxidative stress, poses significant health burdens worldwide. Recent evidence has shed light on the association between the dysbiosis of gut microbiota and COPD, and their metabolites have emerged as potential modulators of disease progression through the intricate gut-lung axis. Here, we demonstrate the efficacy of oral administration of the probiotic Pediococcus pentosaceus SMM914 (SMM914) in delaying the progression of COPD by attenuating pulmonary oxidative stress. Specially, SMM914 induces a notable shift in the gut microbiota toward a community structure characterized by an augmented abundance of probiotics producing short-chain fatty acids and antioxidant metabolisms. Concurrently, SMM914 synthesizes L-tryptophanamide, 5-hydroxy-L-tryptophan, and 3-sulfino-L-alanine, thereby enhancing the tryptophan-melatonin pathway and elevating 6-hydroxymelatonin and hypotaurine in the lung environment. This modulation amplifies the secretion of endogenous anti-inflammatory factors, diminishes macrophage polarization toward the M1 phenotype, and ultimately mitigates the oxidative stress in mice with COPD. The demonstrated efficacy of the probiotic intervention, specifically with SMM914, not only highlights the modulation of intestine microbiota but also emphasizes the consequential impact on the intricate interplay between the gastrointestinal system and respiratory health.


Asunto(s)
Microbioma Gastrointestinal , Melatonina , Probióticos , Enfermedad Pulmonar Obstructiva Crónica , Animales , Ratones , Antioxidantes , Pediococcus pentosaceus , Melatonina/farmacología , Triptófano
7.
Mar Pollut Bull ; 201: 116263, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38531208

RESUMEN

Seasonal variations of environmental parameters usually lead to considerable changes in microbial communities. Nevertheless, the specific response patterns of these communities in coastal areas subjected to different levels of contamination remain unclear. Our results revealed notable fluctuations in the bacterioplankton community both seasonally and spatially, with seasonal variations being particularly significant. The diversity and composition of bacterioplankton communities in the estuaries varied significantly across seasons and between seas. Some bacterial phyla that were highly abundant in the dry season (e.g., Patescibacteria and Epsilonbacteraeota) were almost absent in the wet season. Furthermore, the network analysis revealed that the bacterioplankton networks were more complex during the wet season than in the dry season. In the wet season, the estuarine bacterioplankton network in the Yellow Sea region was more complex and stable, while the opposite was true in the dry season. According to the neutral community model, stochastic processes played a more significant role in the formation of bacterioplankton communities during the wet season than during the dry season. Estuarine bacterioplankton communities in the Yellow Sea region were more affected by stochastic processes compared to those in the Bohai Sea. In summary, in the estuaries of two differently contaminated coastal areas, the seasonal increase in nutrient levels enhanced the deterministic processes and network complexity of the bacterioplankton communities.


Asunto(s)
Estuarios , Microbiota , Organismos Acuáticos , Bacterias , Estaciones del Año , Ecosistema , China
8.
ChemSusChem ; 17(9): e202400241, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38494446

RESUMEN

The design of high activity catalyst for the efficiently conversion of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) gains great interest. The rationally tailoring of electronic structure directly affects the interaction between catalysts and organic substrates, especially molecular oxygen as the oxidant. This work, the bimetallic catalysts AuPd/CeO2 were prepared by the combining method of chemical reduction and photo-deposition, effectively concerting charge between Au and Pd and forming the electron-rich state of Au. The increasing of oxygen vacancy concentration of CeO2 by acidic treatment can facilitate the adsorption of HMF for catalysts and enhance the yield of FDCA (99.0 %). Moreover, a series of experiment results combining with density functional theory calculation illustrated that the oxidation performance of catalyst in HMF conversion was strongly related to the electronic state of interfacial Au-Pd-CeO2. Furthermore, the electron-rich state sites strengthen the adsorption and activation of molecular oxygen, greatly promoting the elimination of ß-hydride for the selective oxidation of 5-hydroxymethyl-2-furancarboxylic acid (HMFCA) to FDCA, accompanied with an outgoing FDCA formation rate of 13.21 mmol ⋅ g-1 ⋅ min-1 at 80 °C. The perception exhibited in this research could be benefit to understanding the effects of electronic state for interfacial sites and designing excellent catalysts for the oxidation of HMF.

9.
Carbohydr Polym ; 334: 122031, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38553230

RESUMEN

The efficacy of cancer therapies is significantly compromised by the immunosuppressive tumor milieu. Herein, we introduce a previously unidentified therapeutic strategy that harnesses the synergistic potential of chitosan-coated bacterial vesicles and a targeted chemotherapeutic agent to activate dendritic cells, thereby reshaping the immunosuppressive milieu for enhanced cancer therapy. Our study focuses on the protein-mediated modification of bacterium-derived minicells with chitosan molecules, facilitating the precise delivery of Doxorubicin to tumor sites guided by folate-mediated homing cues. These engineered minicells demonstrate remarkable specificity in targeting lung carcinomas, triggering immunogenic cell death and releasing tumor antigens and damage-associated molecular patterns, including calreticulin and high mobility group box 1. Additionally, the chitosan coating, coupled with bacterial DNA from the minicells, initiates the generation of reactive oxygen species and mitochondrial DNA release. These orchestrated events culminate in dendritic cell maturation via activation of the stimulator of interferon genes signaling pathway, resulting in the recruitment of CD4+ and CD8+ cytotoxic T cells and the secretion of interferon-ß, interferon-γ, and interleukin-12. Consequently, this integrated approach disrupts the immunosuppressive tumor microenvironment, impeding tumor progression. By leveraging bacterial vesicles as potent dendritic cell activators, our strategy presents a promising paradigm for synergistic cancer treatment, seamlessly integrating chemotherapy and immunotherapy.


Asunto(s)
Quitosano , Neoplasias Pulmonares , Neoplasias , Humanos , Quitosano/uso terapéutico , Inmunomodulación , Neoplasias/tratamiento farmacológico , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Línea Celular Tumoral , Células Dendríticas , Microambiente Tumoral
10.
Chemistry ; 30(7): e202303465, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37985373

RESUMEN

Hydrogen sulfide (H2 S), one of the most important gasotransmitters, plays a critical role in endogenous signaling pathways of many diseases. However, developing H2 S donors with both tunable release kinetics and high release efficiency for subcellular delivery has been challenging. Here, we describe a click and release reaction between pyrone/pyranthiones and bicyclononyne (BCN). This reaction features a release of CO2 /COS with second-order rate constants comparable to Strain-Promoted Azide-Alkyne Cycloaddition reactions (SPAACs). Interestingly, pyranthiones showed enhanced reaction rates compared to their pyrone counterparts. We investigated pyrone biorthogonality and demonstrated their utility in protein labeling applications. Moreover, we synthesized substituted pyranthiones with H2 S release kinetics that can address the range of physiologically relevant H2 S dynamics in cells and achieved quantitative H2 S release efficiency in vitro. Finally, we explored the potential of pyranthiones as H2 S/COS donors for mitochondrial-targeted H2 S delivery in living cells.


Asunto(s)
Sulfuro de Hidrógeno , Pironas , Azidas , Alquinos , Reacción de Cicloadición , Química Clic
11.
Sci Rep ; 13(1): 21086, 2023 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-38030755

RESUMEN

Molecular-genetic imaging has greatly advanced clinical diagnosis and prognosis monitoring. However, the specific visualization of intracellular proteins such as estrogen receptor (ER) and progesterone receptor (PR) remains an elusive goal. Here, we highlight a novel method for selectively detecting ER/PR positive tumors using genetically engineered responsive elements. Our study demonstrates that the double responsive elements of ER/PR exhibit the most sensitivity to the steroid receptors in breast cancers. By utilizing a cationic polymer vector, we constructed a responsive element-fluorescence protein system that can selectively image ER/PR positive breast cancers in murine models under a near-infrared laser. This non-invasive imaging achieved high-resolution detection without death or serious anaphylactic activity in the animals. Our findings suggest that the reporter system consisting of steroid receptor response elements and near-infrared proteins provides a practical system for identifying biomarkers and advancing cancer diagnosis and therapy.


Asunto(s)
Neoplasias , Receptores de Progesterona , Animales , Ratones , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Pronóstico , Imagen Óptica , Estrógenos
12.
Aquat Toxicol ; 264: 106730, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37862730

RESUMEN

Due to human activities, marine organisms are frequently co-stressed with nickel (Ni) pollution and seawater warming; nevertheless, very scarce information is known about their interaction in marine biota under a multigenerational scenario. Here, after verifying the interaction of Ni and warming via a 48-h acute test, we conducted a multigenerational experiment (F0-F2), in which the marine copepod Tigriopus japonicus was exposed to Ni at environmentally realistic concentrations (0, 2, and 20 µg/L) under ambient (22℃) and predicted seawater warming (26℃) conditions. Ni accumulation and the important life history traits were analyzed for each generation. Results showed that Ni exposure caused Ni bioaccumulation and thus compromised the survivorship and egg production of T. japonicus. In particular, seawater warming significantly increased Ni accumulation, thus intensifying the negative effects of Ni on its survivorship and development. Overall, this study suggests that Ni multigenerational exposure even at environmentally realistic concentrations could produce a significant impact on marine copepod's health, and this impact would be intensified under the projected seawater warming, providing a mechanistic understanding of the interaction between warming and Ni pollution in marine organisms from a multigenerational perspective.


Asunto(s)
Copépodos , Contaminantes Químicos del Agua , Animales , Humanos , Níquel/toxicidad , Contaminantes Químicos del Agua/toxicidad , Agua de Mar , Organismos Acuáticos
13.
Cell Signal ; 112: 110920, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37827345

RESUMEN

OBJECTIVE: To assess the influences and underlying mechanism of circular RNA UBR1 (circUBR1) in ventilator-induced lung injury (VILI). METHODS: In mice and mouse alveolar epithelial cells, VILI model was established. CircUBR1 and miR-20a-5p expression was assessed via quantitative real time polymerase chain reaction. Western blot and immunohistochemistry were applied to assess geranylgeranyl diphosphate synthase 1 (GGPPS1) protein expression. In lung tissues, the histopathological changes were utilized using hematoxylin and eosin staining. Cell counting kit-8 assay and flow cytometer were applied to detect cell proliferation and apoptosis. The levels of inflammatory cytokines [interleukin (IL)-1ß, IL-18, IL-6, and tumor necrosis factor (TNF)-α] were measured by western blot and enzyme-linked immunosorbent assay. RESULTS: In lung tissues of VILI mice, circUBR1 and GGPPS1 expression were upregulated, while miR-20a-5p expression was downregulated. In vivo, circUBR1 knockdown alleviated lung injury, inhibited cell apoptosis, and decreased the levels of inflammatory cytokines. In cells treated with cyclic stretch (CS), circUBR1 knockdown promoted cell viability, inhibited cell apoptosis, and reduced inflammatory cytokines. CircUBR1 could sponge miR-20a-5p, and GGPPS1 was the target gene of miR-20a-5p. In addition, in cells treated with CS, downregulation of miR-20a-5p or the overexpression of GGPPS1 reversed the promotive effect of circUBR1 knockdown on cell viability and the inhibitive effect of circUBR1 knockdown on cell apoptosis and inflammation production. CONCLUSIONS: In VILI, knockdown of circUBR1 attenuated lung injury and inflammation via regulating the miR-20a-5p/GGPPS1 pathway. Our study may provide a potential therapeutic target for treatment of VILI.


Asunto(s)
MicroARNs , Lesión Pulmonar Inducida por Ventilación Mecánica , Animales , Ratones , Lesión Pulmonar Inducida por Ventilación Mecánica/genética , Regulación hacia Abajo , Citocinas , Apoptosis/genética , Inflamación , MicroARNs/genética
14.
Inorg Chem ; 62(37): 15277-15292, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37656824

RESUMEN

The construction of strong metal-support interactions in oxide-supported noble metal nanocatalysts has been considered an emerging and efficient way in improving catalytic performance in biomass-upgrading reactions. Herein, a citric acid (CA)-assisted synthesized ZrO2 layer with improved oxygen vacancy (Ov) concentrations on a natural clay mineral of halloysite nanotubes (HNTs) was designed. Moreover, AuxPdy/ZrO2@HNTs-zCA catalysts were prepared by loading AuPd bimetal and employed for aerobic oxidation of the lignocellulosic biomass-derived 5-hydroxymethylfurfural (HMF) platform to the bioplastic monomer 2,5-furandicarboxylic acid (FDCA) with water as the solvent. The results of catalytic experiments revealed that the Au3Pd1/ZrO2@HNTs-1.0CA catalyst exhibited excellent catalytic activity at 0.5 MPa O2, with a satisfactory FDCA yield of 99.5% and outstanding FDCA formation rate of 1057.9 mmol·g-1·h-1. The improved Ov concentration in the ZrO2 support enhanced the adsorption and activation ability of the catalyst for O2, and a higher Lewis acid concentration provided a stronger adsorption ability of the catalyst for reaction substrates. Besides, the synergistic effect of AuPd bimetallic nanoparticles steered the tandem oxidation of aldehyde and alcohol groups in HMF and accelerated the rate-determining step. More importantly, the relationship between the Ov concentration and catalytic performance also demonstrated that the enhanced catalytic activity for HMF oxidation was mainly attributed to the active interface of AuPd-ZrOx. This work offers fresh insights into rationally designing oxygen vacancy-driven strong interactions between the oxide support and noble nanoparticles for the catalytic upgrade of biomass platform chemicals.

15.
Sci Rep ; 13(1): 13481, 2023 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-37596397

RESUMEN

Pseudomonas aeruginosa (P. aeruginosa) infections present a grave threat to immunocompromised individuals, particularly those with cystic fibrosis due to the development of bacterial biofilms. In this study, we engineered self-assembling chitosan-ceftazidime nanoparticles (CSCE) capable of effectively penetrating biofilms and eradicating P. aeruginosa. The CSCE nanoparticles were synthesized through ionic cross-linking, combining negatively charged ceftazidime with positively charged chitosan, resulting in uniform nanoparticles measuring approximately 40 nm in diameter, exhibiting high dispersity and excellent biocompatibility. Remarkably, these nanoparticles exhibited significant inhibition of P. aeruginosa growth, reduced pyocyanin production, and diminished biofilm formation, achieving a maximum inhibition rate of 22.44%. Furthermore, in vivo investigations demonstrated enhanced survival in mice with abdominal P. aeruginosa infection following treatment with CSCE nanoparticles, accompanied by reduced levels of inflammatory cytokines Interleukin-6 (125.79 ± 18.63 pg/mL), Interleukin-17 (125.67 ± 5.94 pg/mL), and Tumor Necrosis Factor-α (135.4 ± 11.77 pg/mL). Critically, mice treated with CSCE nanoparticles showed no presence of bacteria in the bloodstream following intraperitoneal P. aeruginosa infection. Collectively, our findings highlight the potential of these synthesized nanoparticles as effective agents against P. aeruginosa infections.


Asunto(s)
Quitosano , Infecciones Intraabdominales , Nanopartículas , Animales , Ratones , Ceftazidima/farmacología , Pseudomonas aeruginosa , Biopelículas
17.
Front Microbiol ; 13: 997587, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36312915

RESUMEN

Advances in synthetic biology and the clinical application of bacteriotherapy enable the use of genetically engineered bacteria (GEB) to combat various diseases. GEB act as a small 'machine factory' in the intestine or other tissues to continuously produce heterologous proteins or molecular compounds and, thus, diagnose or cure disease or work as an adjuvant reagent for disease treatment by regulating the immune system. Although the achievements of GEBs in the treatment or adjuvant therapy of diseases are promising, the practical implementation of this new therapeutic modality remains a grand challenge, especially at the initial stage. In this review, we introduce the development of GEBs and their advantages in disease management, summarize the latest research advances in microbial genetic techniques, and discuss their administration routes, performance indicators and the limitations of GEBs used as platforms for disease management. We also present several examples of GEB applications in the treatment of cancers and metabolic diseases and further highlight their great potential for clinical application in the near future.

18.
Angew Chem Int Ed Engl ; 61(39): e202209741, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-35934675

RESUMEN

Growing lubricating hydrogel coatings in controllable manners on diverse material surfaces demonstrates promising applications. Here, a surface modification method is reported for in situ growing hydrogel coatings onto surfaces of diverse substrates in the absence of UV assistance. It is performed by decorating substrates with a universal mussel-inspired synthetic adhesive with catechol groups. Upon being immersed in reaction solution, these groups can assist substrate bonding and in situ capture and reduce Fe3+ into Fe2+ for decomposing S2 O8 2- into SO4 - ⋅ catalytically at the interface to initiate interface polymerization of monomers. As a result, hydrogel coatings with controllable thickness could be grown on surfaces of arbitrary substrates to change their surface characteristics regardless of materials size, category, geometry and transparency, implying considerable potential in surface engineering.

19.
Biomacromolecules ; 23(9): 3766-3778, 2022 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-35980819

RESUMEN

It is becoming increasingly important to synthesize efficient biomacromolecule lubricants suitable for medical devices. Even though the development of biomimetic lubricants has made great progress, the current system suitable for hydrophobic silicone-based medical devices is highly limited. In this work, we synthesize one kind of novel polysaccharide-derived macromolecule lubricant of chitosan (CS) grafted polyethylene glycol (PEG) chains and catechol groups (CT) (CS-g-PEG-g-CT). CS-g-PEG-g-CT shows good adsorption ability by applying quantitative analysis of quartz crystal microbalance (QCM), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and confocal fluorescence imaging technique, as well as the typical shear-thinning feature. CS-g-PEG-g-CT exhibits low and stable coefficients of friction (COFs) (0.01-0.02) on polydimethylsiloxane (PDMS) surfaces at a wide range of mass concentrations in diverse media including pure water, physiological saline, and PBS buffer solution and is even tolerant to various normal loads and sliding frequencies for complex pressurizing or shearing environments. Subsequently, systematic surface characterizations are used to verify the dynamic attachment ability of the CS-g-PEG-g-CT lubricant on the loading/shearing process. The lubrication mechanism of CS-g-PEG-g-CT can be attributed to the synergy of strong adsorption from catechol groups to form a uniform assembly layer, excellent hydration effect from PEG chains, and typical shear-thinning feature to dissipate viscous resistance. Surprisingly, CS-g-PEG-g-CT exhibits efficient lubricity on silicone-based commercial contact lenses and catheters. The current macromolecule lubricant demonstrates great real application potential in the fields of medical devices and disease treatments.


Asunto(s)
Polietilenglicoles , Silicio , Catecoles , Lubricantes/química , Lubrificación , Polietilenglicoles/química , Polisacáridos
20.
ACS Appl Mater Interfaces ; 14(32): 36411-36424, 2022 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-35917371

RESUMEN

Despite recent preclinical progress with oncolytic bacteria in cancer therapy, dose-limiting toxicity has been a long-standing challenge for clinical application. Genetic and chemical modifications for enhancing the bacterial tumor-targeting ability have been unable to establish a balance between increasing its specificity and effectiveness while decreasing side effects. Herein, we report a simple, highly efficient method for rapidly self-assembling a clinically used lipid on bacterium and for reducing its minimum effective dose and toxicity to normal organs. The resultant bacteria present the ability to reverse-charge between neutral and acidic solutions, thus enabling weak interactions with the negatively charged normal cells, hence increasing their biocompatibility with blood cells and with the immune system. Additionally, the lipid-coated bacteria exhibit a longer blood circulation lifetime and low tissue trapping compared with the wild-type strains. Thereby, the engineered bacteria show enhanced tumor specificity and effectiveness even at low doses. Multiple visualization techniques are used for vividly demonstrating the time course of bacterial circulation in the blood and normal organs after intravenous administration. We believe that these methods for biointerfacial lipid self-assembly and evaluation of bacterial systemic circulation possess vast potential in exquisitely fabricating engineered bacteria for cancer therapy in the future.


Asunto(s)
Neoplasias , Bacterias , Humanos , Lípidos , Neoplasias/tratamiento farmacológico , Electricidad Estática
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