SEARCH · Search PubMed

Results for “Polyurethane”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

6 recordsLinked to original sources

PubMed2026

Preparation and study of non-thrombotic and biostable sulfobetaine-modified small-diameter polyurethane vascular grafts.

A novel sulfobetaine-modified polysiloxane-polycarbonate polyurethane (ZSiPCU) was synthesized. In vitro characterizations revealed that polysiloxane surface enrichment endowed the material with excellent biostability. Importantly, sulfobetaine zwitterions formed a robust hydration layer, effectively suppressing protein adsorption and platelet adhesion to ensure outstanding hemocompatibility. Furthermore, the material supported the adhesion and proliferation of vascular endothelial cells, confirming its cytocompatibility, while its elastomeric matrix provided rapid mechanical self-sealing capabilities. Electrospun ZSiPCU grafts were evaluated in a 3-month rat abdominal aorta model, maintaining high patency rates and facilitating in situ luminal endothelialization and smooth muscle cell remodeling. Additionally, superior puncture resistance of the grafts was demonstrated by puncture tests, with complete hemostasis achieved within 2 mins through mechanical self-sealing.

Polyurethanes↗

PubMed2026

Reversed unidirectional transport in a Janus polyurethane/alginate dressing for directional postbiotic delivery to infected wounds.

Probiotic-derived postbiotics exhibit significant potential for infected wound control; however, their effective and localized delivery at wound sites remains a challenge. This study developed a polyurethane/alginate composite nonwoven via electrospinning to establish a postbiotic delivery platform for Bifidobacterium bifidum BD-1 (PU/Alg/BD-1). The beaded fibrous hydrophobic PU layer and hydrophilic Alg layer form a wettability gradient, enabling reversed unidirectional fluid transport toward the wound interface while inhibiting backflow. In vitro results showed that PU/Alg/BD-1 exhibited significant antibacterial activity against Staphylococcus aureus and Escherichia coli and good cytocompatibility with a hemolysis rate of <5%. Targeted metabolomic analysis revealed multiple organic acids in the BD-1 metabolites, which contributed to its antibacterial activity. In vivo microbial analysis verified that PU/Alg/BD-1 effectively reduced the relative abundance of Staphylococcus at the wound site while increasing the proportions of Corynebacterium and Psychrobacter. This microbial modulation contributed to infection control in a rat full-thickness infected wound model, accompanied by a shift in the macrophage phenotype and the downregulation of inflammatory factors including IL-6, TNF-α, and TGF-β in the PU/Alg/BD-1 group. Compared with the blank control, conventional gauze, PU/Alg, and BD-1 groups, PU/Alg/BD-1 significantly promoted wound contraction and re-epithelialization and enhanced collagen deposition. Hence, this study provides an effective material construction strategy for the application of probiotic-derived postbiotics to promote wound healing, demonstrates the potential of BD-1 to regulate the wound microenvironment and accelerate healing, and thereby offers a novel approach for the treatment of infected wounds.

Journal Article↗

PubMed2026

Effect of Various Types of Remineralizing Agents on the Remineralization of Mild and Moderate Defects Caused by Molar-Incisor Hypomineralization in Mexican Schoolchildren: A 12-month Follow-up Randomized Clinical Trial.

PURPOSE: Using Laser-Induced Fluorescence (LIF), this study aimed to evaluate the effect of three remineralizing agents on permanent molars and incisors with both mild and moderate Molar-Incisor Hypomineralization (MIH) in 8-to-12-year-old Mexican schoolchildren. MATERIALS AND METHODS: In this randomized clinical trial, 104 children were selected to participate and then divided randomly into four groups: Group I: control, Oral-B kids (toothpaste); Group II: Fluor Protector (varnish); Group III: Clinpro White Varnish; and Group IV: MI Paste (CCP-ACP). Both varnishes were applied once every four weeks for twelve months for each group. Remineralization was evaluated by LIF at intervals of 1, 3, 6, 9, and 12 months. Paired-sample t-tests and repeated-measures ANOVA were performed, while the Greenhouse-Geisser correction was used to evaluate sphericity. RESULTS: The three test agents used increased the level of remineralization observed at the site of mild and moderate MIH defects over the course of twelve months (p0.001). A similar decrease in average LIF values was observed across the three treatment groups. CONCLUSIONS: The use of both fluoride varnishes and the CPP-ACP toothpaste was observed to promote the remineralization of both mild and moderate MIH defects.

Humans↗

PubMed2026

Shielding performance and clinical applicability of lead-free materials in computed tomography.

Owing to the high radiation exposure associated with computed tomography (CT) examinations and the image quality degradation caused by conventional radiation shielding materials, this study evaluated the dose reduction performance and image quality maintenance potential of a newly developed lead-free composite shielding material. This material was composed of bismuth, tungsten, tungsten carbide, aluminium, and polyurethane. Phantom-based dose measurements demonstrated that the shielding material achieved dose reduction rates ranging from 17.6% to 37.6%, depending on tube voltage. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and changes in tube current-time product (mAs) under a scout-based automatic exposure control (AEC) protocol were analysed according to the presence or absence of the shielding material across regions. For the clinical evaluation, CT scans were performed on four patients. Furthermore, the images were reviewed to evaluate whether this material affected image quality. The shielding material exhibited radiation reduction levels comparable to those reported in previous studies. SNR and CNR analyses showed minor statistical variations in certain regions; however, most differences were not statistically significant, and even significant differences remained within a range that did not compromise diagnostic image quality. Under the scout-based AEC protocol, the use of the shielding material resulted in less than 1% variation in mAs values. No visually perceptible artefacts or clinically significant image quality degradation were observed. The proposed composite shielding material demonstrated the potential to mitigate some limitations of conventional shielding materials and showed preliminary clinical feasibility as an adjunctive strategy for radiation dose reduction in CT examinations.

Radiation Protection↗

PubMed2026

Microplastic contamination in South Asian commercially important seafood: A comprehensive assessment of occurrence, source, and human health risk.

Seafood is a cornerstone of global food security and human nutrition, serving as the primary source of animal protein for more than one-fourth of the global population, with South Asia representing one of the world's fastest-growing seafood-consuming regions. However, escalating microplastic (MP) pollution in marine ecosystems poses an emerging threat to seafood safety and human health, yet a comprehensive regional assessment of MP contamination in South Asian seafood remains lacking. This study presents the first region-wide systematic synthesis of the literature on MP contamination in commercially important seafood across South Asia, integrating occurrence patterns, human exposure assessment, polymer-specific hazard evaluation, and bibliometric analysis to address this critical knowledge gap. The meta-analysis estimated an average microplastic exposure of 145 particles/person/day through seafood consumption in South Asia, with fish contributing the highest intake (121 particles/person/day). The detected polymers were classified into PHI hazard levels I-IV, with polyvinyl chloride (PVC), polyurethane (PU), and polyacrylamide (PAM) representing the highest hazard categories. The mean pollution load index (PLI) was 7.71 (Category I), with crustaceans exhibiting the highest contamination (PLI = 10.07). Polypropylene was the predominant polymer, whereas fragments and blue particles were the most frequently reported microplastic characteristics. These findings provide the first regional baseline for assessing microplastic contamination, polymer-associated hazards, and human exposure through seafood consumption in South Asia, underscoring the need for standardized monitoring and targeted mitigation strategies to safeguard seafood safety and public health.

Animals↗

PubMed2026

Ageing effects on chemical, physical, mechanical, and morphological properties of clear aligners - a systematic review.

BACKGROUND: Clear aligner (CA) therapy has experienced rapid use over the past two decades to treat orthodontic malocclusions. However, evidence on CA material degradation in the oral environment remains limited and often focuses on single brands or isolated material properties. OBJECTIVES: To investigate CA ageing characteristics across different materials and brands and evaluate the chemical, physical, mechanical, and morphological changes following simulated or intraoral ageing. SEARCH METHODS: Five databases (PubMed, Web of Science, MEDLINE [Ovid], ProQuest, and Scopus) were searched to 18 March 2026, with no restrictions. ELIGIBILITY CRITERIA: Studies assessing CA properties after intraoral use or simulated ageing (thermocycling, cyclic loading, or liquid immersion) were included. DATA COLLECTION AND ANALYSIS: Study selection followed PRISMA 2020. RoB was assessed using QUIN for purely in vitro studies, JBI for cohort in vivo studies, and Cochrane RoB 2 for RCTs. Results were synthesised narratively and organised by property domain, as substantial methodological heterogeneity precluded formal meta-analysis. Where protocols were comparable, a simple pooled weighted mean was calculated and presented graphically. RESULTS: Ninety-five studies were included. RoB was low in eight studies, moderate in sixty-two, and high in twenty-five. Chemical composition remained largely stable during ageing, though some brands showed trace elemental release. Physical, mechanical, and morphological properties showed material-dependent deterioration. Pooled discolouration was greatest with coffee (weighted mean ΔE = 70.9), versus tea (ΔE = 18.4) and red wine (ΔE = 11.5), with Invisalign® consistently exceeding the clinically perceptible threshold. Force decay of 40-90% typically occurred within 48 h. Thermoplastic polyurethane (TPU)-based and directly printed aligners (DPAs) generally showed greater susceptibility than polyethylene terephthalate glycol-modified (PETG)-based aligners, though findings on hardness, roughness, and stiffness were inconsistent. CONCLUSIONS: CA materials undergo clinically relevant degradation during use, particularly in TPU-based and DPAs aligners. Clinicians may need to prioritise material-specific protocols, reinforce dietary and cleaning instructions, and consider force decay when determining aligner replacement intervals. PROSPERO number: CRD420251110248.

Humans↗