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1.
Chembiochem ; 24(2): e202200582, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36346708

RESUMEN

Peptides can self-assemble into various hierarchical nanostructures through noncovalent interactions and form functional materials exhibiting excellent chemical and physical properties, which have broad applications in bio-/nanotechnology. The self-assembly mechanism, self-assembly morphology of peptide supramolecular architecture and their various applications, have been widely explored which have the merit of biocompatibility, easy preparation, and controllable functionality. Herein, we introduce the latest research progress of self-assembling peptide-based nanomaterials and review their applications in biomedicine and optoelectronics, including tissue engineering, anticancer therapy, biomimetic catalysis, energy harvesting. We believe that this review will inspire the rational design and development of novel peptide-based functional bio-inspired materials in the future.


Asunto(s)
Materiales Biomiméticos , Nanoestructuras , Materiales Biocompatibles/química , Péptidos/química , Nanoestructuras/química , Nanotecnología
2.
Nat Mater ; 21(3): 359-365, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35190655

RESUMEN

Ionogels are compelling materials for technological devices due to their excellent ionic conductivity, thermal and electrochemical stability, and non-volatility. However, most existing ionogels suffer from low strength and toughness. Here, we report a simple one-step method to achieve ultra-tough and stretchable ionogels by randomly copolymerizing two common monomers with distinct solubility of the corresponding polymers in an ionic liquid. Copolymerization of acrylamide and acrylic acid in 1-ethyl-3-methylimidazolium ethyl sulfate results in a macroscopically homogeneous covalent network with in situ phase separation: a polymer-rich phase with hydrogen bonds that dissipate energy and toughen the ionogel; and an elastic solvent-rich phase that enables for large strain. These ionogels have high fracture strength (12.6 MPa), fracture energy (~24 kJ m-2) and Young's modulus (46.5 MPa), while being highly stretchable (~600% strain) and having self-healing and shape-memory properties. This concept can be applied to other monomers and ionic liquids, offering a promising way to tune ionogel microstructure and properties in situ during one-step polymerization.


Asunto(s)
Líquidos Iónicos , Conductividad Eléctrica , Geles/química , Enlace de Hidrógeno , Líquidos Iónicos/química , Polímeros
3.
J Evid Based Dent Pract ; 23(3): 101897, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37689446

RESUMEN

OBJECTIVES: Evidence of oral microbiota perturbations has been accumulated for lung cancers. This review focused on the oral microbiota alterations in population suffering from lung cancer. In addition, we also discussed conflicting data about the association between oral microbiota dysbiosis and risk of lung cancer. METHODS: A systematic search was conducted in Medline, Embase, PubMed, and Cochrane Library databases. The studies evaluated diversity and abundance of oral microbes in healthy and lung cancer individuals as well as association of periodontal disease and pathogens with lung cancer. Of 3559 studies, 28 included studies were performed in qualitative analysis, and 25 studies were used in meta-analyses for quantitative assessment. Heterogeneity was analyzed by using I² and chi-squared Q test statistics. Statistical analyses were performed by using the RevMan 5.4 software. RESULTS: Compared with the control, lung cancer patients had lower alpha diversity (Shannon: SMD = -0.54; 95% CI, -0.90 to -0.19; P < .01, I2 = 71%). In nested case-control studies, individuals with decreased alpha diversity tended to have an increased risk of lung cancer (observed species: HR = 0.90; 95% CI, 0.85-0.96; P < .01, I2 = 0%; Shannon: HR = 0.89; 95% CI, 0.83-0.95; P < .01, I2 = 0%). Overall, no strong evidence of association of relative abundance with specific oral microbes with lung cancers was found because of inconsistent data. No associations were found between periodontal pathogens and lung cancer risk (red complex: HR = 1.12, 95% CI: 0.42-3.02, P = .82, I2 = 62%; orange complex: HR =1.77, 95% CI: 0.78-3.98, P = .17, I2 = 36%), expect for Fusobacterium nucleatum (HR = 2.27, 95% CI: 1.13-4.58, P = .02, I2 = 0%). The positive association of periodontal disease with lung cancer risk was found (HR = 1.58, 95% CI: 1.25-2.00, P < .001, I2= 0%) with increase of periodontal diseases severity (HR = 2.39, 95% CI: 1.57-3.66, P < .001, I2 = 0%). However, such association was not found in never-smoker participants (HR = 1.00, 95% CI: 0.76-1.31, P = .37, I2= 7%). CONCLUSIONS: Lower alpha diversity of oral microbiome may be associated with a greater risk of lung cancer and might serve as a predictive signal of lung cancer risk. There was no strong evidence of relative abundance of oral microbial taxa and periodontal pathogens in lung cancer patients. Fusobacterium nucleatum might be a potential microbial candidate of biomarkers in lung cancer. Periodontal disease may be positively associated with lung cancer risk by confounding of smoking, but not an independent risk factor.


Asunto(s)
Neoplasias Pulmonares , Microbiota , Enfermedades Periodontales , Humanos , Estudios de Casos y Controles , Proyectos de Investigación
4.
Small ; 18(23): e2201643, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35532205

RESUMEN

Recent years have witnessed the rapid development of sustainable materials. Along this line, developing biodegradable or recyclable soft electronics is challenging yet important due to their versatile applications in biomedical devices, soft robots, and wearables. Although some degradable bulk hydrogels are directly used as the soft electronics, the sensing performances are usually limited due to the absence of distributed conducting circuits. Here, sustainable hydrogel-based soft electronics (HSE) are reported that integrate sensing elements and patterned liquid metal (LM) in the gelatin-alginate hybrid hydrogel. The biopolymer hydrogel is transparent, robust, resilient, and recyclable. The HSE is multifunctional; it can sense strain, temperature, heart rate (electrocardiogram), and pH. The strain sensing is sufficiently sensitive to detect a human pulse. In addition, the device serves as a model system for iontophoretic drug delivery by using patterned LM as the soft conductor and electrode. Noncontact detection of nearby objects is also achieved based on electrostatic-field-induced voltage. The LM and biopolymer hydrogel are healable, recyclable, and degradable, favoring sustainable applications and reconstruction of the device with new functions. Such HSE with multiple functions and favorable attributes should open opportunities in next-generation electronic skins and hydrogel machines.


Asunto(s)
Hidrogeles , Dispositivos Electrónicos Vestibles , Alginatos , Biopolímeros , Electrónica , Humanos
5.
Molecules ; 27(3)2022 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-35164213

RESUMEN

Lung cancer is the most commonly diagnosed cancer and the leading cause of cancer death worldwide. Numerous drugs have been developed to treat lung cancer patients in recent years, whereas most of these drugs have undesirable adverse effects due to nonspecific distribution in the body. To address this problem, stimuli-responsive drug delivery systems are imparted with unique characteristics and specifically deliver loaded drugs at lung cancer tissues on the basis of internal tumor microenvironment or external stimuli. This review summarized recent studies focusing on the smart carriers that could respond to light, ultrasound, pH, or enzyme, and provided a promising strategy for lung cancer therapy.


Asunto(s)
Antineoplásicos/farmacología , Preparaciones de Acción Retardada/farmacología , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Nanopartículas/administración & dosificación , Neoplasias/tratamiento farmacológico , Materiales Inteligentes/farmacología , Animales , Humanos , Concentración de Iones de Hidrógeno , Nanopartículas/química
6.
Small ; 16(26): e2000203, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32452630

RESUMEN

Turning insulating silk fibroin materials into conductive ones turns out to be the essential step toward achieving active silk flexible electronics. This work aims to acquire electrically conductive biocompatible fibers of regenerated Bombyx mori silk fibroin (SF) materials based on carbon nanotubes (CNTs) templated nucleation reconstruction of silk fibroin networks. The electronical conductivity of the reconstructed mesoscopic functional fibers can be tuned by the density of the incorporated CNTs. It follows that the hybrid fibers experience an abrupt increase in conductivity when exceeding the percolation threshold of CNTs >35 wt%, which leads to the highest conductivity of 638.9 S m-1 among organic-carbon-based hybrid fibers, and 8 times higher than the best available materials of the similar types. In addition, the silk-CNT mesoscopic hybrid materials achieve some new functionalities, i.e., humidity-responsive conductivity, which is attributed to the coupling of the humidity inducing cyclic contraction of SFs and the conductivity of CNTs. The silk-CNT materials, as a type of biocompatible electronic functional fibrous material for pressure and electric response humidity sensing, are further fabricated into a smart facial mask to implement respiration condition monitoring for remote diagnosis and medication.


Asunto(s)
Conductividad Eléctrica , Fibroínas , Nanotubos de Carbono , Respiración , Seda , Animales , Materiales Biocompatibles/química , Técnicas Biosensibles/instrumentación , Bombyx , Fibroínas/química , Humedad , Seda/química
7.
New Phytol ; 226(2): 410-425, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31849071

RESUMEN

Ferulate 5-hydroxylase (F5H) is a limiting enzyme involved in biosynthesizing sinapyl (S) monolignol in angiosperms. Genetic regulation of F5H can influence S monolignol synthesis and therefore improve saccharification efficiency and biofuel production. To date, little is known about whether F5H is post-transcriptionally regulated by endogenous microRNAs (miRNAs) in woody plants. Here, we report that a microRNA, miR6443, specifically regulates S lignin biosynthesis during stem development in Populus tomentosa. In situ hybridization showed that miR6443 is preferentially expressed in vascular tissues. We further identified that F5H2 is the direct target of miR6443. Overexpression of miR6443 decreased the transcript level of F5H2 in transgenic plants, resulting in a significant reduction in S lignin content. Conversely, reduced miR6443 expression by short tandem target mimics (STTM) elevated F5H2 transcripts, therefore increasing S lignin composition. Introduction of a miR6443-resistant form of F5H2 into miR6443-overexpression plants restored lignin ectopic composition, supporting that miR6443 specifically regulated S lignin biosynthesis by repressing F5H2 in P. tomentosa. Furthermore, saccharification assays revealed decreased hexose yields by 7.5-24.5% in miR6443-overexpression plants compared with the wild-type control, and increased hexoses yields by 13.2-14.6% in STTM6443-overexpression plants. Collectively, we demonstrate that miR6443 modulates S lignin biosynthesis by specially regulating F5H2 in P. tomentosa.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Lignina/biosíntesis , MicroARNs/genética , Populus , Proteínas de Arabidopsis , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente/metabolismo , Populus/genética , Populus/metabolismo , Madera/genética , Madera/metabolismo
8.
FASEB J ; 33(9): 9858-9870, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31166803

RESUMEN

Wound healing, especially for diabetic wounds, is a lengthy and complicated process involving interactions and responses at the protein, cell, and tissue levels. Loading of growth factors into a hydrogel to construct a sustained-release system is considered a promising approach to improve wound healing. The present study investigates the effect of thermosensitive heparin-poloxamer (HP) hydrogel-encapsulated recombinant human fibroblast growth factor 21 (rhFGF21) on wound healing in mice with streptozotocin-induced diabetes mellitus. First, we studied the in vitro release of rhFGF21 from the rhFGF21-HP coacervate. The results showed that HP might control the release of rhFGF21. Next, we examined the effect of rhFGF21-HP on skin wound healing in diabetic mice. Our data showed that rhFGF21-HP significantly improved wound closure; promoted granulation, collagen deposition, and re-epithelialization; and enhanced the expression of CD31. Moreover, rhFGF21-HP had obvious advantages in diabetic wound healing. Therefore, the results suggest that the rhFGF21-HP hydrogel polymer plays an important role in skin wound healing. This work provides a suitable sustained-release delivery system that can continuously release rhFGF21 and presents a promising therapeutic strategy for wound healing in patients with diabetes.-Liu, H., Zhao, Y., Zou, Y., Huang, W., Zhu, L., Liu, F., Wang, D., Guo, K., Hu, J., Chen, J., Ye, L., Li, X., Lin, L. Heparin-poloxamer hydrogel-encapsulated rhFGF21 enhances wound healing in diabetic mice.


Asunto(s)
Diabetes Mellitus Experimental , Factores de Crecimiento de Fibroblastos/farmacología , Heparina/química , Hidrogeles/química , Poloxámero/química , Cicatrización de Heridas/efectos de los fármacos , Animales , Glucemia , Formas de Dosificación , Liberación de Fármacos , Factores de Crecimiento de Fibroblastos/administración & dosificación , Factores de Crecimiento de Fibroblastos/química , Prueba de Tolerancia a la Glucosa , Humanos , Insulina , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Recombinantes
9.
J Nanobiotechnology ; 17(1): 102, 2019 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-31581945

RESUMEN

Natural extracellular matrices (ECMs) are three-dimensional (3D) and multi-scale hierarchical structure. However, coatings used as ECM-mimicking structures for osteogenesis are typically two-dimensional or single-scaled. Here, we design a distinct quasi-three-dimensional hierarchical topography integrated of density-controlled titania nanodots and nanorods. We find cellular pseudopods preferred to anchor deeply across the distinct 3D topography, dependently of the relative density of nanorods, which promote the osteogenic differentiation of osteoblast but not the viability of fibroblast. The in vivo experimental results further indicate that the new bone formation, the relative bone-implant contact as well as the push-put strength, are significantly enhanced on the 3D hierarchical topography. We also show that the exposures of HFN7.1 and mAb1937 critical functional motifs of fibronectin for cellular anchorage are up-regulated on the 3D hierarchical topography, which might synergistically promote the osteogenesis. Our findings suggest the multi-dimensions and multi-scales as vital characteristic of cell-ECM interactions and as an important design parameter for bone implant coatings.


Asunto(s)
Sustitutos de Huesos/química , Nanotubos/química , Osteogénesis , Titanio/química , Animales , Diferenciación Celular , Línea Celular , Supervivencia Celular , Fibroblastos/citología , Masculino , Ratones , Nanotubos/ultraestructura , Osteoblastos/citología , Prótesis e Implantes , Conejos
10.
J Craniofac Surg ; 30(2): 541-547, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30730510

RESUMEN

OBJECTIVE: Temporomandibular joint (TMJ) dislocation means the condyle moves out of the normal position. There are several treatments for TMJ dislocation, including conservative treatment, injection treatment, minimally invasive treatment, and open surgical treatment. In this study, we tried to review the literature related to the augmentation of the articular eminence and proposed a modified eminoplasty technique of TMJ dislocation by computer-aided design and computer-aided manufacturing (CAD/CAM) cutting guides. METHODS: The literature on eminoplasty for TMJ was reviewed with 3 charts. Besides, 2 (67 and 69 years old) patients with chronic recurrent dislocation were treated by the CAD/CAM-guided surgical technique in our study, and postoperative measures were recorded to verify the safety and effectiveness regarding this technique. RESULTS: A total of 28 studies (including 268 patients) of the augmentation of the articular eminence have been reported since 1967, including the 2 present patients. According to the analysis of the recurrence and complications in the review, we found the modified technique had an obvious advantage. The technique with cutting guides was also found having higher accuracy. CONCLUSION: The modified technique was a reliable method when treating the TMJ dislocation, and the combination of CAD/CAM cutting guides was useful for more accuracy, even reduced the operation difficulty.


Asunto(s)
Diseño Asistido por Computadora , Luxaciones Articulares/cirugía , Procedimientos Quirúrgicos Orales/métodos , Osteotomía/métodos , Articulación Temporomandibular/lesiones , Anciano , Humanos , Modelos Anatómicos , Recurrencia , Articulación Temporomandibular/diagnóstico por imagen , Articulación Temporomandibular/cirugía , Cigoma/diagnóstico por imagen , Cigoma/cirugía
11.
Macromol Rapid Commun ; 39(14): e1700715, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29292584

RESUMEN

A novel n-type polymer of PTDI-T based on asymmetric rylene diimide and thiophene is designed and synthesized. The highest power conversion efficiency of 4.70% is achieved for PTB7-Th:PTDI-T-based devices, which is obviously higher than those of the analogue polymers of PPDI-2T and PDTCDI. When using PBDB-T as a donor, an open-circuit voltage (VOC ) as high as 1.03 V is obtained. The results indicate asymmetric rylene diimide is a kind of promising building block to construct n-type photovoltaic polymers.


Asunto(s)
Fulerenos/química , Imidas/química , Polímeros/química , Energía Solar , Imidas/síntesis química , Polímeros/síntesis química , Luz Solar , Tiofenos/síntesis química , Tiofenos/química
12.
Water Sci Technol ; 76(9-10): 2380-2388, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29144296

RESUMEN

Polymer-supported hydrated iron(III) oxide (PHIO) was successfully applied as adsorbent for arsenic removal in a wastewater treatment plant in Nandan, China. The practical PHIO adsorbent samples (PHIO-P) were collected from the adsorption column of the wastewater treatment plant, and desorption experiments of the adsorbent were carried out. Our results showed that the formation of precipitates on the surface of PHIO-P might block the porous channel of the adsorbent and decrease its arsenic adsorption capacity. In the dynamic arsenic desorption experiment, the arsenic desorption equilibrium was achieved more quickly at decreasing desorption velocity, and higher arsenic desorption efficiency was obtained at increasing NaOH concentration in regenerant. It was found that the PHIO-P adsorbent could be well regenerated at 1.0 M NaOH solution and desorption velocity of 5 BV h-1. Comparing with the raw adsorbent, the maximum arsenic adsorption capacity of PHIO-P decreased by 41.1% after practical running for 26 months. Additionally, the frequently used waste PHIO adsorbent could be treated as non-hazardous material in the arsenic-containing wastewater treatment process after long-time use.


Asunto(s)
Arsénico/química , Compuestos Férricos/química , Polímeros/química , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , China , Concentración de Iones de Hidrógeno , Purificación del Agua/instrumentación
13.
J Oral Maxillofac Surg ; 74(1): 55-67, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26375368

RESUMEN

Severe tridimensional alveolar ridge defects complicate the placement of dental implants, and surgical removal of some oral tumors might not leave adequate bone for dental implant placement. Regenerating an adequate amount of bone vertically and horizontally to achieve a satisfying outcome for well-osseointegrated implants and thus ensure long-term success of implant restoration is challenging. This report describes the clinical feasibility of a simple approach using a screw tent-pole combined with guided bone regeneration to augment complicated tridimensional alveolar ridge defects in a case of extensive bone loss due to maxillary tumor surgery. Titanium screws were arranged in "tented" fashion to provide stable room for bone regeneration. Regenerated bone was achieved and 2 more implants were placed in the regenerated ridge 10 months later, leading to a successful maxillary prosthesis.


Asunto(s)
Aumento de la Cresta Alveolar/métodos , Regeneración Ósea/fisiología , Tornillos Óseos , Regeneración Tisular Dirigida/instrumentación , Neoplasias Maxilares/cirugía , Alveoloplastia/métodos , Materiales Biocompatibles/química , Arco Dental/cirugía , Implantes Dentales , Prótesis Dental de Soporte Implantado , Dentadura Parcial Fija , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Maxilar/cirugía , Planificación de Atención al Paciente , Titanio/química , Adulto Joven
14.
J Mech Behav Biomed Mater ; 152: 106462, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38346366

RESUMEN

OBJECTIVES: To study the stress distribution and bonding performance in posterior occlusal veneers and tooth bodies under different preparation forms and materials. METHODS: An isolated lower right first molar was prepared with non-retention type (type A), cavity-retained type (type B), and encircling-retention type (type C) forms. MicroCT images of the tooth were obtained and digitally converted into three-dimensional solid models. Three-dimensional models of veneers for the three abutment teeth were designed, fabricated, and divided into nine models (AEM, ALU, AVE, BEM, BLU, BVE, CEM, CLU, and CVE) according to the material used (E.max CAD [EM], Lava Ultimate [LU] and Vita Enamic [VE]). Three-dimensional finite element stress analysis was performed by applying vertical and oblique forces (200 N) to simulate chewing loads using ABAQUS. Finally, an adhesive stiffness degradation diagram was obtained using the rotatory dislocation simulation method. RESULTS: The BEM model had the largest equivalent stress extreme value (160.50 MP A) when a vertical load was applied to the veneers, while there was no significant difference when it was applied to dental tissues. The equivalent stress extreme values of each part under an oblique load were significantly greater than those under a vertical load. The AEM model had the largest values when the loads were applied to the veneers (350.60 MP A) and the dental tissues (40.13 MP A). The equivalent stress extreme values of the veneers were ranked as LU < VE < EM for different materials, and LU > VE > EM for dental tissues. Bonding performance results were C > B ≈ A and LU > VE > EM. CONCLUSIONS: The cavity-retained type better protected the veneers and dental tissues than the non-retention and encircling-retention types under lateral forces. E.max CAD material, with a high elastic modulus, reduced the stress transmitted to the remaining dental tissues. Lava Ultimate exhibited the best bonding performance.


Asunto(s)
Diente Molar , Análisis de Elementos Finitos , Simulación por Computador , Módulo de Elasticidad
15.
Anal Chim Acta ; 1296: 342332, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38401940

RESUMEN

Isoniazid (INH) is crucial in the treatment of tuberculosis; however, its overuse may induce significant gastrointestinal and hepatic side effects. On October 27, 2017, the International Agency for Research on Cancer, under the auspices of the World Health Organization, published a list of carcinogens for preliminary collation and reference. Isoniazid was categorized as a Group 3 carcinogen. The efficient detection of INH poses an important and challenging task. In this study, a "synergistic effect" is incorporated into the pillar (Yamagishi and Ogoshi, 2018) [5] arene-based macrocyclic host (DPA) by strategically attaching bis-p-hydroxybenzoic acid groups to the opposite ends of the pillar (Yamagishi and Ogoshi, 2018) [5] arene. This combination endows DPA with a reversible and selective fluorescence response to isoniazid. Additionally, DPA exhibits excellent analytical capabilities for isoniazid, including speed and selectivity, with a detection limit as low as 4.85 nM. Concurrently, DPA can self-assemble into a microsphere structure, which is convertible into micrometer-sized tubular structures through host-guest interactions with isoniazid. The introduction of a competitive guest, trimethylamine, enables the reversion to its microsphere structure. Consequently, this study presents an innovative and straightforward synthetic approach for smart materials that facilitates the reversible morphological transition between microspheres and microtubes in response to external chemical stimuli. This discovery provides a valuable strategy for designing "synergistic effects" in constructing trace-level isoniazid-responsive interfaces, with potential applications across various fields, such as controlled drug delivery.


Asunto(s)
Materiales Inteligentes , Isoniazida , Sistemas de Liberación de Medicamentos , Microesferas
16.
Macromol Biosci ; 24(4): e2300401, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38154146

RESUMEN

Shape memory polymer (SMP) vascular grafts are promising interventional vascular grafts for cardiovascular disease (CAD) treatment; However, hemocompatibility and biocompatibility, which are the critical issues for the SMP vascular grafts, are not systematically concerned. Furthermore, the water-induced SMP grafts are more convenient and safer than the thermally induced ones in case of the bioapplication. Herein, in this work, the new water-induced expanded bilayer vascular graft with the inner layer of crosslinked poly(ε-caprolactone) (cPCL) and the outer layer of water-induced SMP of regenerated chitosan/polyvinyl alcohol (RCS/PVA) are prepared by hot pressing and programming approaches. The results show that the inner and outer layer surfaces of the prepared grafts are smooth, and they exhibit good interfacial interaction properties. The bilayer grafts show good mechanical properties and can be expanded in water with a diameter expansion of ≈30%. When compared with commercial expanded polytetrafluoroethylene (ePTFE), the bilayer graft shows better hemocompatibility (platelet adhesion, hemolysis rate, various clotting times, and plasma recalcification time (PRT)) and in vitro and in vivo biocompatibility, which thus is a promising material for the vascular graft.


Asunto(s)
Injerto Vascular , Agua , Ensayo de Materiales , Prótesis Vascular , Alcohol Polivinílico/farmacología , Politetrafluoroetileno
17.
Int J Biol Macromol ; 268(Pt 1): 131746, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38653425

RESUMEN

Biodegradable poly(L-lactic acid) (PLLA) has seldom used for dairy packaging due to medium permeability and brittleness. Novel PLLA copolymers, poly (L-lactic acid-co-butylene itaconate-co-glycolic acid) (PLBIGA), were developed by integrating glycolic acid (GA) and poly(butylene itaconate) (PBI) into PLLA's structure using low molecular weight PLLA as a key initiator. Then, packaging materials with better barrier and mechanical properties were obtained by blended PLBIGA with PLLA. Both PLLA/PLBIGA films and polyethylene nylon composite film (PE/NY) were used for stirred yogurt packaging and storage at 4 °C for 25 days. Results revealed that yogurt packed by PLLA/PLBIGA films maintained stabler water-holding capacity, color, and viscosity over the storage period. Moreover, the integrity of the gel structure and the total viable count of lactic acid bacteria in yogurt packaged in PLLA/40-PLBIGA8 were also found to be superior to those in PE/NY packages, highlighting its eco-friendly advantages in dairy packaging.


Asunto(s)
Embalaje de Alimentos , Almacenamiento de Alimentos , Poliésteres , Yogur , Yogur/microbiología , Poliésteres/química , Embalaje de Alimentos/métodos , Almacenamiento de Alimentos/métodos , Succinatos/química , Conservación de Alimentos/métodos , Glicolatos/química , Viscosidad , Polímeros/química
18.
Food Chem ; 449: 139218, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38579656

RESUMEN

High costs and low performance have constrained the application of bio-based materials in food packaging. Herein, a series of ultra-thin poly(L-lactic acid-iconic acid N-diol) (P(LA-NI)) copolymer films were developed using a "one-step" polycondensation process with integrated toughness, barrier properties, gas selectivity, and quality control features. The massive branched structure and gg conformers in P(LA-NI) act as "internal chain expansion" and "internal plasticization". Meanwhile, P(LA-NI) contains numerous polar groups and unique nanoscale microphase structures to realize excellent CO2, O2 barrier, CO2/O2 selectivity, anti-fogging, and UV shielding functions. The atmosphere within the package spontaneously achieves the desirable low O2 and high CO2 levels when packaging button mushrooms with high respiratory metabolism. Eventually, the shelf life of button mushrooms reached 24 days, >3-fold extended. This PLLA-based film meets "dual carbon" and "food safety" goals and has vast potential for fresh food preservation.


Asunto(s)
Dióxido de Carbono , Embalaje de Alimentos , Oxígeno , Poliésteres , Embalaje de Alimentos/instrumentación , Poliésteres/química , Dióxido de Carbono/química , Oxígeno/química , Conservación de Alimentos/métodos , Conservación de Alimentos/instrumentación , Permeabilidad
19.
Adv Healthc Mater ; 13(15): e2303870, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38412305

RESUMEN

Magnesium ions are highly enriched in early stage of biological mineralization of hard tissues. Paradoxically, hydroxyapatite (HAp) crystallization is inhibited significantly by high concentration of magnesium ions. The mechanism to regulate magnesium-doped biomimetic mineralization of collagen fibrils has never been fully elucidated. Herein, it is revealed that citrate can bioinspire the magnesium-stabilized mineral precursors to generate magnesium-doped biomimetic mineralization as follows: Citrate can enhance the electronegativity of collagen fibrils by its absorption to fibrils via hydrogen bonds. Afterward, electronegative collagen fibrils can attract highly concentrated electropositive polyaspartic acid-Ca&Mg (PAsp-Ca&Mg) complexes followed by phosphate solution via strong electrostatic attraction. Meanwhile, citrate adsorbed in/on fibrils can eliminate mineralization inhibitory effects of magnesium ions by breaking hydration layer surrounding magnesium ions and thus reduce dehydration energy barrier for rapid fulfillment of biomimetic mineralization. The remineralized demineralized dentin with magnesium-doped HAp possesses antibacterial ability, and the mineralization mediums possess excellent biocompatibility via cytotoxicity and oral mucosa irritation tests. This strategy shall shed light on cationic ions-doped biomimetic mineralization with antibacterial ability via modifying collagen fibrils and eliminating mineralization inhibitory effects of some cationic ions, as well as can excite attention to the neglected multiple regulations of small biomolecules, such as citrate, during biomineralization process.


Asunto(s)
Materiales Biomiméticos , Ácido Cítrico , Magnesio , Polielectrolitos , Magnesio/química , Magnesio/farmacología , Polielectrolitos/química , Ácido Cítrico/química , Materiales Biomiméticos/química , Materiales Biomiméticos/farmacología , Animales , Durapatita/química , Durapatita/farmacología , Péptidos/química , Péptidos/farmacología , Calcio/química , Calcio/metabolismo , Humanos , Cationes/química , Antibacterianos/farmacología , Antibacterianos/química , Colágeno/química , Biomimética/métodos
20.
mSystems ; 9(7): e0008924, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38940519

RESUMEN

The gastric microbial community plays a fundamental role in gastric cancer (GC), and the two main anatomical subtypes of GC, non-cardia and cardia GC, are associated with different risk factors (Helicobacter pylori for non-cardia GC). To decipher the different microbial spatial communities of GC, we performed a multicenter retrospective analysis to characterize the gastric microbiota in 223 GC patients, including H. pylori-positive or -negative patients, with tumors and paired adjacent normal tissues, using third-generation sequencing. In the independent validation cohort, both dental plaque and GC tumoral tissue samples were collected and sequenced. The prevalence of H. pylori and oral-associated bacteria was verified using fluorescence in situ hybridization (FISH) assays in GC tumoral tissues and matched nontumoral tissues. We found that the vertical distribution of the gastric microbiota, at the upper, middle, and lower third sites of GC, was likely an important factor causing microbial diversity in GC tumor tissues. The oral-associated microbiota cluster, which included Veillonella parvula, Streptococcus oralis, and Prevotella intermedia, was more abundant in the upper third of the GC. However, H. pylori was more abundant in the lower third of the GC and exhibited a significantly high degree of microbial correlation. The oral-associated microbiota module was co-exclusive with H. pylori in the lower third site of the GC tumoral tissue. Importantly, H. pylori-negative GC patients with oral-associated gastric microbiota showed worse overall survival, while the increase in microbial abundance in H. pylori-positive GC patients showed no difference in overall survival. The prevalence of V. parvula in both the dental plaque and GC tissue samples was concordant in the independent validation phase. We showed that the oral-associated species V. parvula and S. oralis were correlated with overall survival. Our study highlights the roles of the oral-associated microbiota in the upper third of the GC. In addition, oral-associated species may serve as noninvasive screening tools for the management of GC and an independent prognostic factor for H. pylori-negative GCs. IMPORTANCE: Our study highlights the roles of the oral-associated microbiota in the upper third of gastric cancer (GC).We showed that the oral-associated species Veillonella parvula and Streptococcus oralis were correlated with overall survival. In addition, oral-associated species may serve as noninvasive screening tools for the management of GC and an independent prognostic factor for Helicobacter pylori-negative GCs.


Asunto(s)
Helicobacter pylori , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología , Helicobacter pylori/genética , Helicobacter pylori/aislamiento & purificación , Helicobacter pylori/patogenicidad , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/patología , Microbioma Gastrointestinal/genética , Boca/microbiología , Microbiota/genética
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