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1.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(4): 853-860, 2024 Jul 20.
Artigo em Zh | MEDLINE | ID: mdl-39170003

RESUMO

Objective: This study aims to develop a medical patch surface material featuring a microporous polyurethane (PU) membrane and to assess the material's properties and biological performance. The goal is to enhance the clinical applicability of pelvic floor repair patch materials. Methods: PU films with a microporous surface were prepared using PU prepolymer foaming technology. The films were produced by optimizing the PU prepolymer isocyanate index (R value) and the relative humidity (RH) of the foaming environment. The surface morphology of the PU microporous films was observed by scanning electron microscopy, and the chemical properties of the PU microporous films, including hydrophilicity, were analyzed using infrared spectroscopy, Raman spectroscopy, and water contact angle measurements. In vitro evaluations included testing the effects of PU microporous film extracts on the proliferation of L929 mouse fibroblasts and observing the adhesion and morphology of these fibroblasts. Additionally, the effect of the PU microporous films on RAW264.7 mouse macrophages was studied. Immune response and tissue regeneration were assessed in vivo using Sprague Dawley (SD) rats. Results: The PU films exhibited a well-defined and uniform microporous structure when the R value of PU prepolymer=1.5 and the foaming environment RH=70%. The chemical structure of the PU microporous films was not significantly altered compared to the PU films, with a significantly lower water contact angle ([55.7±1.5]° ) compared to PU films ([69.5±1.7]° ) and polypropylene (PP) ([ 104.3±2.5]°), indicating superior hydrophilicity. The extracts from PU microporous films demonstrated good in vitro biocompatibility, promoting the proliferation of L929 mouse fibroblasts. The surface morphology of the PU microporous films facilitated fibroblast adhesion and spreading. The films also inhibited the secretion of tumor necrosis factor-α (TNF-α) and interleukin (IL)-1ß by RAW264.7 macrophages while enhancing IL-10 and IL-4 secretion. Compared to 24 hours, after 72 hours of culture, the expression levels of TNF-α and IL-1ß were reduced in both the PU film and PU microporous film groups and were significantly lower than those in the PP film group (P<0.05), with the most notable decreases observed in the PU microporous film group. IL-10 and IL-4 levels increased significantly in the PU microporous film group, surpassing those in the PP film group (P<0.01), with the most pronounced increase in IL-4. The PU microporous film induced mild inflammation with no significant fibrous capsule formation in vivo. After 60 days of implantation, the film partially degraded, showing extensive collagen fiber growth and muscle formation in its central region. Conclusion: The PU microporous film exhibits good hydrophilicity and biocompatibility. Its surface morphology enhances cell adhesion, regulates the function of RAW264.7 macrophages, and promotes tissue repair, offering new insights for the design of pelvic floor repair and reconstruction patch materials.


Assuntos
Fibroblastos , Polipropilenos , Poliuretanos , Ratos Sprague-Dawley , Poliuretanos/química , Animais , Camundongos , Ratos , Polipropilenos/química , Fibroblastos/citologia , Materiais Biocompatíveis/química , Telas Cirúrgicas , Células RAW 264.7 , Propriedades de Superfície , Linhagem Celular , Porosidade , Teste de Materiais , Proliferação de Células/efeitos dos fármacos , Macrófagos/citologia
2.
BMC Oral Health ; 23(1): 894, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37986181

RESUMO

OBJECTIVES: To evaluate the effects of the alveolar ridge split (ARS) technique on gained horizontal width of the alveolar ridge and implant survival rate. MATERIALS AND METHODS: Electronic searching was performed in six electronic databases (Pubmed, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, China National Knowledge Infrastructure, and SIGLE) from January 1, 2010, to November 1, 2023. Two authors performed study selection, data extraction, and study qualities (ROBINS-I and RoB 2.0) independently. Meta-analysis was performed by Comprehensive meta-analysis 3.0. RESULTS: 24 included studies were observational, and 1 study was a randomized controlled trial (RCT). 14 studies investigated the gained width of the horizontal alveolar ridge, and 17 examined the implants' survival rate. For assessment of risk of bias, nine studies were high risk of bias and 16 studies were moderate risk of bias. Meta-analysis demonstrated that the pooled gained alveolar ridge width was 3.348 mm (95%CI: 4.163 mm, 2.533 mm), and the implant survival rate was 98.1% (95%CI: 98.9%, 96.9%). Seven studies showed seven different complications including exposure, infection, bad split, dehiscence, fracture, paresthesia and soft tissue retraction. CONCLUSION: Recent ARS technique seems to be an effective method of bone augmentation with enough gained width and a high implant survival rate. Further long-term and RCTs research remains needed to enhance the study quality. CLINICAL RELEVANCE: The ARS technique could generate sufficient bone volume, and implants had a high-level survival rate. Therefore, ARS has been proposed to be a reliable horizontal bone augmentation technique that creates good conditions for the implantation of narrow alveolar crests.


Assuntos
Aumento do Rebordo Alveolar , Implantes Dentários , Humanos , Implantação Dentária Endóssea/métodos , Aumento do Rebordo Alveolar/métodos , Processo Alveolar/cirurgia , Transplante Ósseo , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Macromol Rapid Commun ; 43(21): e2200490, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35836315

RESUMO

Biodegradable shape memory polymers are promising biomaterials for stents used in minimally invasive surgical procedures such as intestinal stents. Herein, a series of biodegradable shape memory polyurethanes (SMPUs) containing a novel phenylalanine-derived chain extender (PHP) are synthesized. Inspired by the fact that the function of biomacromolecules such as proteins is rich and varied because of the multiple combinations of the amino acid in highly evolved biosystems, this study finds that the sequence distribution of PHP in SMPU will also have a great influence on the phase structure and degradation behavior, especially the difference of surface morphology caused by degradation. Considering that the transition temperature (Ttrans ) of SMPU obtained is higher than physiological temperature, oxidized carbon black (OCB) with the ability of photothermal conversion is introduced into SMPU, which can not only endow SMPU with near-infrared response shape recovery characteristics, but also enhance phase separation degree and mechanical properties of them. SMPU/OCB composites show excellent shape memory effect and rapid photothermal response, and they can be degraded by chymotrypsin with an adjustable degradation rate. These SMPU/OCB composites show broad potential for application as intestinal stents.


Assuntos
Poliuretanos , Materiais Inteligentes , Poliuretanos/química , Quimotripsina , Materiais Biocompatíveis/química , Temperatura
4.
BMC Oral Health ; 21(1): 579, 2021 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-34772376

RESUMO

BACKGROUND: Osseointegration is essential for the success and stability of implants. Platelet concentrates were reported to enhance osseointegration and improve implant stability. The purpose of this review is to systematically analyze the effects of platelet concentrates on implant stability and marginal bone loss. METHODS: Two researchers independently performed searches in the following databases (last searched on 21 July 2021): MEDLINE (PubMed), Cochrane Library, EMBASE, and Web of Science. In addition, a manual search was carried out on references of relevant reviews and initially included studies. All randomized controlled trials (RCTs) and controlled clinical trials (CCTs) on the application of platelet concentrates in the implant surgery procedure were included. The risk of bias of RCTs and CCTs were assessed with a revised Cochrane risk of bias tool for randomized trials (RoB 2.0) and the risk of bias in non-randomized studies-of interventions (ROBINS-I) tool, respectively. Meta-analyses on implant stability and marginal bone loss were conducted. Researchers used mean difference or standardized mean difference as the effect size and calculated the 95% confidence interval. In addition, subgroup analysis was performed based on the following factors: type of platelet concentrates, method of application, and study design. RESULTS: Fourteen studies with 284 participants and 588 implants were included in the final analysis. 11 studies reported implant stability and 5 studies reported marginal bone level or marginal bone loss. 3 studies had high risk of bias. The meta-analysis results showed that platelet concentrates can significantly increase implant stability at 1 week (6 studies, 302 implants, MD 4.26, 95% CI 2.03-6.49, P < 0.001) and 4 weeks (8 studies, 373 implants, MD 0.67, 95% CI 0.46-0.88, P < 0.001) after insertion, significantly reduced marginal bone loss at 3 months after insertion (4 studies, 95 implants, mesial: MD - 0.33, 95% CI - 0.46 to - 0.20, P < 0.001; distal: MD - 0.38, 95% CI - 0.54 to - 0.22, P < 0.001). However, the improvement of implant stability at 12 weeks after insertion was limited (P = 0.10). Subgroup analysis showed that PRP did not significantly improve implant stability at 1 week and 4 weeks after insertion (P = 0.38, P = 0.17). Platelet concentrates only placed in the implant sites did not significantly improve implant stability at 1 week after insertion (P = 0.20). CONCLUSIONS: Platelet concentrates can significantly improve implant stability and reduce marginal bone loss in the short term. Large-scale studies with long follow-up periods are required to explore their long-term effects and compare effects of different types. TRIAL REGISTRATION: This study was registered on PROSPERO, with the Registration Number being CRD42021270214.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Humanos , Osseointegração
5.
Biomacromolecules ; 21(4): 1460-1470, 2020 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-32119533

RESUMO

The hydrolysis of a newly synthesized polyether urethane (PEU) that uses polydimethylsiloxane (PDMS) as a second macrodiol and fluorinated diol (FDO) as another chain extender has been studied via immersion in buffer solutions at 70 °C. The hydrolysis process was monitored using scanning electron microscopy (SEM), gel permeation chromatography (GPC), and tensile testing. After aging for 32 weeks, no surface defect was observed on the fluorinated silicon-containing PEUs (FSPEU). Meanwhile, the addition of FDO did not alter the other issues of bulk hydrolysis, such as the changes in molecular weight and mechanical strength. Moreover, microphase separation of FSPEU was suppressed during temperature-accelerated hydrolysis, whereas aging induced a more noticeable phase of morphological change in silicon-modified PEUs (SPEU) due to the hindrance effect of the fluorinated side chains. The formation of hydrolysis-prone allophanate is also reduced in the presence of FDO. FSPEU with enhanced antihydrolysis performance can potentially be applied to biostable medical devices.


Assuntos
Materiais Biocompatíveis , Silício , Hidrólise , Teste de Materiais , Microscopia Eletrônica de Varredura , Poliuretanos
6.
Biomacromolecules ; 19(6): 2137-2145, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29669212

RESUMO

The degradation behaviors including oxidation and hydrolysis of silicone modified polycarbonate urethanes were thoroughly investigated. These polyurethanes were based on polyhexamethylene carbonate (PHMC)/polydimethylsiloxane (PDMS) mixed macrodiols with molar ratio of PDMS ranging from 5% to 30%. It was proved that PDMS tended to migrate toward surface and even a small amount of PDMS could form a silicone-like surface. Macrophages-mediated oxidation process indicated that the PDMS surface layer was desirable to protect the fragile soft PHMC from the attack of degradative species. Hydrolysis process was probed in detail after immersing in boiling buffered water using combined analytical tools. Hydrolytically stable PDMS could act as protective shields for the bulk to hinder the chain scission of polycarbonate carbonyls whereas the hydrolysis of urethane linkages was less affected. Although the promoted phase separation at higher PDMS fractions lead to possible physical defects and mechanical compromise after degradation, simultaneously enhanced oxidation and hydrolysis resistance could be achieved for the polyurethanes with proper PDMS incorporation.


Assuntos
Dimetilpolisiloxanos , Macrófagos/metabolismo , Cimento de Policarboxilato , Poliésteres , Poliuretanos , Animais , Dimetilpolisiloxanos/farmacocinética , Dimetilpolisiloxanos/farmacologia , Hidrólise , Macrófagos/citologia , Camundongos , Oxirredução , Cimento de Policarboxilato/química , Cimento de Policarboxilato/farmacocinética , Cimento de Policarboxilato/farmacologia , Poliésteres/química , Poliésteres/farmacocinética , Poliésteres/farmacologia , Poliuretanos/química , Poliuretanos/farmacocinética , Poliuretanos/farmacologia , Células RAW 264.7
7.
Macromol Rapid Commun ; 38(23)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29083102

RESUMO

Shape-memory polymers are highly desirable in implant biomaterials for minimally invasive surgical procedures. However, most of them lack suitable transition temperature, mechanical properties, and biodegradability. Here, a series of shape-memory polyurethanes are synthesized by postcrosslinking in hard-segment domains using a flexible crosslinker. The materials used are all nontoxic and biodegradable. Through postcrosslinking of unsaturated linear polyurethanes with flexible and biodegradable crosslinker, the crosslinked polyurethanes (CPUs) show good mechanical properties, excellent shape-memory property, and repeatability. The post-crosslinking structure and shape-memory mechanism of CPUs are investigated by Fourier transform infrared spectroscopy, differential scanning calorimetry, and dynamic mechanical analysis tests. The crosslinker endows the fixed phase enough crosslinking and inserts in the hard segments to give the fixed phase certain elasticity. The elastic hard segments make them form more hydrogen bonds with soft segments during shape deformation. The low-molecular-weight poly (ε-caprolactone) offers the samples a shape-memory transition temperature at around 37 °C, which is suitable for implant devices in vivo. This work expands CPUs with an elastic crosslinking structure as potential candidates for implant biomaterials. Since the post-crosslinking polymerization is facile, it can be convenient for industrial production.


Assuntos
Materiais Biocompatíveis/química , Poliuretanos/química , Varredura Diferencial de Calorimetria , Ligação de Hidrogênio , Teste de Materiais
8.
Biomacromolecules ; 17(6): 2148-59, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27133950

RESUMO

A challenge in the development of multifunctional drug delivery systems is to establish a reasonable and effective synthetic route for multifunctional polymer preparation. Herein, we propose a unique protocol to prepare multifunctional micelles by a cross-assembly process using three different functional polyurethanes incorporating acidic sensitive hydrazone, folic acid for active targeting, and gemini quaternary ammonium (GQA) as efficient cell uptake ligands, respectively. These multifunctional mixed micelles (GFHPMs) have been endowed tunable particle sizes and zeta potential and a unique three-order-layer cross-assemble structure. Their drug-loading contents have been significantly improved, and drug release profiles displayed controlled release of their payloads under acid condition. The folate and GQA ligands showed a synergistic effect to enhance the cell uptake. Biodistribution and antitumor effect of these micelles were systematically investigated in vivo, the mixed micelles could penetrate into the depths of tumors, and drug concentrations in tumors reached the maximum of 6.5% ID/g at 24 h, resulting in an excellent therapeutic effect that the volumes of tumors treated with GFHPM are five times smaller than those treated with blank micelles. Our present work provides an effective approach to the design of multifunctional nanocarriers for tumor-targeted and programmed intracellular drug delivery.


Assuntos
Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Polímeros/farmacologia , Poliuretanos/química , Animais , Apoptose/efeitos dos fármacos , Portadores de Fármacos/química , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Micelas , Neoplasias/patologia , Polímeros/administração & dosagem , Polímeros/química , Distribuição Tecidual , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Lancet ; 381(9882): 2024-32, 2013 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-23726161

RESUMO

BACKGROUND: A vaccine for enterovirus 71 (EV71) is needed to address the high burden of disease associated with infection. We assessed the efficacy, safety, immunogenicity, antibody persistence, and immunological correlates of an inactivated alum-adjuvant EV71 vaccine. METHODS: We did a randomised, double-blind, placebo-controlled, phase 3 trial. Healthy children aged 6-35 months from four centres in China were randomly assigned (1:1) to receive vaccine or alum-adjuvant placebo at day 0 and 28, according to a randomisation list (block size 30) generated by an independent statistician. Investigators and participants and their guardians were masked to the assignment. Primary endpoints were EV71-associated hand, foot, and mouth disease (HFMD) and EV71-associated disease during the surveillance period from day 56 to month 14, analysed in the per-protocol population. This study is registered with ClinicalTrials.gov, number NCT01508247. FINDINGS: 10,245 participants were enrolled and assigned: 5120 to vaccine versus 5125 to placebo. 4907 (with three cases of EV71-associated HFMD and eight cases of EV71-associated disease) versus 4939 (with 30 cases of EV71-associated HFMD and 41 cases of EV71-associated disease) were included in the primary efficacy analysis. Vaccine efficacy was 90·0% (95% CI 67·1-96·9) against EV71-associated HFMD (p=0·0001) and 80·4% (95% CI 58·2-90·8) against EV71-associated disease (p<0·0001). Serious adverse events were reported by 62 of 5117 (1·2%) participants in the vaccine group versus 75 of 5123 (1·5%) in the placebo group (p=0·27). Adverse events occurred in 3644 (71·2%) versus 3603 (70·3%; p=0·33). INTERPRETATION: EV71 vaccine provides high efficacy, satisfactory safety, and sustained immunogenicity. FUNDING: China's 12-5 National Major Infectious Disease Program, Beijing Vigoo Biological.


Assuntos
Enterovirus Humano A/imunologia , Infecções por Enterovirus/prevenção & controle , Vacinas Virais/imunologia , Adjuvantes Imunológicos/efeitos adversos , Compostos de Alúmen , Anticorpos Antivirais/sangue , Pré-Escolar , Método Duplo-Cego , Infecções por Enterovirus/imunologia , Feminino , Humanos , Imunidade Ativa/fisiologia , Lactente , Estimativa de Kaplan-Meier , Masculino , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Vacinas Virais/efeitos adversos
10.
Artigo em Inglês | MEDLINE | ID: mdl-39075020

RESUMO

The alveolar ridge split (ARS) technique is a pivotal advancement in dental implantology, addressing the limitation of insufficient bone width for implant placement. This review traces the historical development of ARS from its initial conceptualization to current practices and future directions. Emphasizing the technique's development, indications, procedural overview, and osteotomy variations, we highlight its minimally invasive nature, which reduces patient morbidity and treatment time. This article reviews various osteotomy methods within ARS, examining their applications, benefits, and limitations. Furthermore, it discusses the technique's role in expanding treatment options for patients with compromised alveolar structures, underpinned by a high implant survival rate and the potential for immediate implant placement. We also cover the necessity of meticulous surgical technique, the importance of patient-specific factors, and the promising future of ARS facilitated by advancements in biomaterials and regenerative medicine. In summary, this review provides a comprehensive overview of ARS, offering valuable insights for dental professionals and informing future clinical practices and research in implantology.

11.
Adv Sci (Weinh) ; 11(16): e2308538, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38350723

RESUMO

Underwater adhesives with injectable, organic solvent-free, strong, fast adhesion, and hemostatic properties have become an urgent need in biomedical field. Herein, a novel polyurethane underwater adhesive (PUWA) inspired by mussels is developed utilizing the rapid post-cure reaction of isocyanate esterification without organic solvents. The PUWA is created through the injectable two component curing process of component A (biocompatible polyurethane prepolymer) and component B (dopamine modified lysine derivatives: chain extender-LDA and crosslinker-L3DA). The two-component adhesive cures quickly and firmly underwater, with an impressive bonding strength of 40 kPa on pork skin and excellent burst pressure of 394 mmHg. Moreover, the PUWA exhibits robust adhesion strength in hostile environments with acid, alkali and saline solutions. Combined with excellent biocompatibility and hemostatic performance, the PUWA demonstrates effectively sealing wounds and promoting healing. With the ability to bond diverse substrates rapidly and strongly, the PUWA holds significant potential for application in both biomedical and industrial fields.


Assuntos
Adesivos , Hemostáticos , Poliuretanos , Poliuretanos/química , Animais , Adesivos/química , Hemostáticos/química , Hemostáticos/farmacologia , Teste de Materiais , Cicatrização/efeitos dos fármacos , Materiais Biocompatíveis/química , Suínos , Adesivos Teciduais/química
12.
J Mater Chem B ; 12(25): 6063-6078, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38888153

RESUMO

Injectable hydrogels have attracted significant interest in the biomedical field due to their minimal invasiveness and accommodation of intricate scenes. Herein, we developed an injectable polyurethane-based thermogel platform by modulating the hydrophilic-hydrophobic balance of the segmented components with pendant PEG. The thermogelling behavior is achieved by a combination of the bridging from the hydrophilic PEG and the percolated network from the hydrophobic micelle core. Firstly, the thermogelation mechanism of this system was demonstrated by both DPD simulation and experimental investigation. The gelling temperature could be modulated by varying the solid content, the component of soft segments, and the length of the pendant PEG. We further applied 3D printing technology to prepare personalized hydrogel structures. This integration highlights the adaptability of our thermogel for fabricating complex and patient-specific constructs, presenting a significant advance in the field of regenerative medicine and tissue engineering. Subsequently, in vitro cell experiments demonstrated that the thermogel had good cell compatibility and could promote the proliferation and migration of L929 cells. Impressively, A549 cells could be expediently in situ parceled in the thermogel for three-dimensional cultivation and gain lifeful 3D cell spheres after 7 days. Further, in vivo experiments demonstrated that the thermogel could promote wound healing with the regeneration of capillaries and hair follicles. Ultimately, our study demonstrates the potential of hydrogels to prepare personalized hydrogel structures via 3D printing technology, offering innovative solutions for complex biomedical applications. This work not only provides a fresh perspective for the design of injectable thermogels but also offers a promising avenue to develop thermoresponsive waterborne polyurethane for various medical applications.


Assuntos
Hidrogéis , Micelas , Poliuretanos , Poliuretanos/química , Humanos , Animais , Hidrogéis/química , Camundongos , Cicatrização/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Proliferação de Células/efeitos dos fármacos , Temperatura , Técnicas de Cultura de Células em Três Dimensões/métodos , Injeções , Movimento Celular/efeitos dos fármacos , Tamanho da Partícula
13.
Small Methods ; 8(7): e2301518, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38517272

RESUMO

Ice-templated porous biomaterials possess transformative potential in regenerative medicine; yet, scaling up ice-templating processes for broader applications-owing to inconsistent pore formation-remains challenging. This study reports an innovative semi-solid freeze-casting technique that draws inspiration from semi-solid metal processing (SSMP) combined with ice cream-production routines. This versatile approach allows for the large-scale assembly of various materials, from polymers to inorganic particles, into isotropic 3D scaffolds featuring uniformly equiaxed pores throughout the centimeter scale. Through (cryo-)electron microscopy, X-ray tomography, and finite element modeling, the structural evolution of ice grains/pores is elucidated, demonstrating how the method increases the initial ice nucleus density by pre-fabricating a semi-frozen slurry, which facilitates a transition from columnar to equiaxed grain structures. For a practical demonstration, as-prepared scaffolds are integrated into a bilayer tissue patch using biodegradable waterborne polyurethane (WPU) for large-scale oral mucosal reconstruction in minipigs. Systematic analyses, including histology and RNA sequencing, prove that the patch modulates the healing process toward near-scarless mucosal remodeling via innate and adaptive immunomodulation and activation of pro-healing genes converging on matrix synthesis and epithelialization. This study not only advances the field of ice-templating fabrication but sets a promising precedent for scaffold-based large-scale tissue regeneration.


Assuntos
Congelamento , Mucosa Bucal , Alicerces Teciduais , Alicerces Teciduais/química , Animais , Porosidade , Suínos , Engenharia Tecidual/métodos , Porco Miniatura , Poliuretanos/química , Materiais Biocompatíveis/química , Gelo , Medicina Regenerativa/métodos
14.
J Mater Chem B ; 12(28): 6968-6980, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38915270

RESUMO

Postoperative adhesions, a prevalent complication following abdominal surgery, affect 90% of patients undergoing abdominal surgical procedures. Currently, the primary approach to prevent postoperative adhesions involves physical isolation of the surgical site and surrounding tissues using a hydrogel; however, this method represents a rudimentary strategy. Herein, considering the impact of oxidative stress and free radicals on postoperative adhesion during wound healing, an injectable antioxidant hydrogel, named PU-OHA-D, was successfully synthesized, which is formed by the crosslinking of dopamine-modified oxidized hyaluronic acid (OHA-D) and dihydrazide-terminated polyurethane (PU-ADH) through hydrazone bonding. PU-OHA-D hydrogel possesses versatile characteristics such as rapid gel formation, injectability, self-repair capability and biodegradability. Additionally, they exhibit an excellent ability to clear free radicals and superior tissue adhesion. PU-OHA-D can be injected in situ to form a hydrogel to prevent abdominal wall-cecum adhesion. Importantly, it can effectively eliminate free radicals and inhibit oxidative stress at the wound site. Thereby, it leads to collagen physiological degradation and prevents the occurrence of postoperative adhesions. The bioinspired hydrogel demonstrates its great potential in preventing postoperative adhesion and promoting wound healing.


Assuntos
Antioxidantes , Hidrogéis , Aderências Teciduais/prevenção & controle , Antioxidantes/química , Antioxidantes/farmacologia , Hidrogéis/química , Animais , Camundongos , Complicações Pós-Operatórias/prevenção & controle , Ácido Hialurônico/química , Estresse Oxidativo/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Humanos , Poliuretanos/química , Ratos
15.
ACS Appl Mater Interfaces ; 16(13): 15970-15980, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38501704

RESUMO

Despite the rapid development of tissue adhesives, flaws including allergies, poor stability, and indiscriminate double-sided adhesive properties limit their application in the medical field. In this work, Janus polyurethane patches were spontaneously prepared by adjusting the difference in the functional group distribution between the top and bottom sides of the patch during emulsion drying. Consequently, poor adhesion was exhibited on the bottom surface, while the top surface can easily adhere to metals, polymers, glasses, and tissues. The difference in adhesive strength to pork skin between the two surfaces is more than 5 times. The quaternary ammonium salt and hydrophilic components on the surface of the polyurethane patch enable the rapid removal and absorption of water from the tissue surface to achieve wet adhesion. Animal experiments have demonstrated that this multifunctional Janus polyurethane patch can promote skin wound closure and healing of infected wounds. This facile and effective strategy to construct Janus polyurethane patch provides a promising method for the development of functional tissue-adhesives.


Assuntos
Adesivos , Adesivos Teciduais , Animais , Adesivos/farmacologia , Poliuretanos/farmacologia , Cicatrização , Pele , Adesivos Teciduais/farmacologia , Antibacterianos/farmacologia , Hidrogéis
16.
J Nanosci Nanotechnol ; 13(1): 68-76, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23646699

RESUMO

In this paper, we successfully synthesized amino-terminated poly(ethylene glycol)-block-poly (epsilon-caprolactone) (NH2-PEG-PCL) block copolymer from polyethylene glycol 2000, epsilon-caprolactone (epsilon-CL) and hydrazine hydrate. The obtained copolymer was characterized by nuclear magnetic resonance (1H-NMR), the molecular weight and distribution of NH2-PEG-PCL were characterized by Gel permeation chromatography (GPC). The NH2-PEG-PCL copolymer could self-assemble into micelles in water. Paclitaxel (PTX) loaded NH2-PEG-PCL (PNPP) micelles were prepared by solid dispersion technique without organic solvent. The micelles were characterized by XRD, TEM and Malvern laser particle size. The results of this work indicated that PNPP micelles were uniform and spherical shapes in solution. The average size and zeta potential of PNPP (DL = 8%) in water was about 97.1 +/- 1.2 nm, +13.9 +/- 0.6 mV, respectively. The in vitrodrug release profile of PNPP micelles showed a clear slow-release effect. The results suggested that NH2-PEG-PCL copolymer might be an excellent carrier for hydrophobic drugs such as PTX. In particular, the NH2-PEG-PCL polymer has potential value for modifying with ligands to work as active targeting drug delivery carriers, which has great significance for cancer therapeutics.


Assuntos
Preparações de Ação Retardada/química , Etilenoglicóis/química , Nanocápsulas/química , Nanocápsulas/ultraestrutura , Paclitaxel/química , Poliésteres/química , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Difusão , Teste de Materiais , Paclitaxel/administração & dosagem , Tamanho da Partícula
17.
J Hematol Oncol ; 16(1): 116, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-38037103

RESUMO

Inflammation is a fundamental defensive response to harmful stimuli, but the overactivation of inflammatory responses is associated with most human diseases. Reactive oxygen species (ROS) are a class of chemicals that are generated after the incomplete reduction of molecular oxygen. At moderate levels, ROS function as critical signaling molecules in the modulation of various physiological functions, including inflammatory responses. However, at excessive levels, ROS exert toxic effects and directly oxidize biological macromolecules, such as proteins, nucleic acids and lipids, further exacerbating the development of inflammatory responses and causing various inflammatory diseases. Therefore, designing and manufacturing biomaterials that scavenge ROS has emerged an important approach for restoring ROS homeostasis, limiting inflammatory responses and protecting the host against damage. This review systematically outlines the dynamic balance of ROS production and clearance under physiological conditions. We focus on the mechanisms by which ROS regulate cell signaling proteins and how these cell signaling proteins further affect inflammation. Furthermore, we discuss the use of potential and currently available-biomaterials that scavenge ROS, including agents that were engineered to reduce ROS levels by blocking ROS generation, directly chemically reacting with ROS, or catalytically accelerating ROS clearance, in the treatment of inflammatory diseases. Finally, we evaluate the challenges and prospects for the controlled production and material design of ROS scavenging biomaterials.


Assuntos
Materiais Biocompatíveis , Estresse Oxidativo , Humanos , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo/fisiologia , Materiais Biocompatíveis/uso terapêutico , Proteínas/metabolismo , Inflamação , Anti-Inflamatórios
18.
Materials (Basel) ; 16(8)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37109791

RESUMO

Anterior teeth problems affect the patient's daily eating, communication, social activities, self-confidence, and mental health. The trend in dentistry is to address anterior tooth problems with minimally invasive and aesthetic treatments. With the development of adhesive materials and ceramics, micro-veneers have been proposed as an alternative treatment for enhancing the aesthetic appearance and avoiding unnecessary tooth reduction. A micro-veneer is a veneer that can be cemented to the surface without or with minimal tooth preparation. These benefits include no need for anesthesia, postoperative insensitivity, good adhesion to enamel, reversibility of treatment, and higher patient acceptance. However, the micro-veneer repair is suitable only for specific cases and must be strictly controlled regarding indication. Treatment planning is a crucial step to achieving functional and aesthetic rehabilitation, and following the clinical protocol is helpful for the longevity and success of micro-veneer restorations. However, more precise and predictable tooth preparation methods, such as minimally invasive microscopic tooth preparation and digitally guided veneer preparation, are recommended rather than the traditional free-hand method. Therefore, this paper clarifies micro-veneers and compares them with other restorations to gain a deeper and more comprehensive understanding. The authors also review indications, materials, cementation, and effect evaluation of micro-veneers to provide clinicians with valuable information. In conclusion, micro-veneers are minimally invasive treatments that provide good restoration results when used appropriately and are worthy of promotion for the aesthetic restoration of anterior teeth.

19.
Colloids Surf B Biointerfaces ; 230: 113518, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37690226

RESUMO

Development of an inflammation modulating polypropylene (PP) mesh in pelvic floor repair is an urgent clinical need. This is because PP mesh for pelvic floor repair can cause a series of complications related to foreign body reactions (FBR) in postoperative period. Therefore, we successfully prepared PP composite mesh that can scavenge reactive oxygen species (ROS) and inhibit inflammation to moderate FBR by a simple method. First, a pregel layer was formed on PP mesh by dip coating. Among them, polyurethane with polythioketal (PTK) is an excellent ROS scavenger, and dopamine methacrylamide (DMA) improves the stability of the coating and synergistically scavenges ROS. Then, a composite mesh (optimal PU50-PP) was obtained by photopolymerization. The results showed that the polyurethane gel layer was able to scavenge more than 90% of free radicals and about 75% of intracellular ROS. In vitro, PU50-PP mesh significantly scavenged ROS and resisted macrophage adhesion. After implantation in the posterior vaginal wall of rats, PU50-PP eliminated 53% of ROS, inhibited inflammation (decreased IL-6, increased IL-10), and dramatically reduced collagen deposition by about 64%, compared to PP mesh. Thus, the composite PP mesh with ROS scavenging and anti-inflammatory properties provides a promising approach for mitigating FBR.


Assuntos
Polipropilenos , Poliuretanos , Animais , Ratos , Feminino , Polipropilenos/farmacologia , Poliuretanos/farmacologia , Espécies Reativas de Oxigênio , Telas Cirúrgicas , Diafragma da Pelve , Reação a Corpo Estranho , Inflamação/tratamento farmacológico , Anti-Inflamatórios
20.
Biomater Adv ; 154: 213607, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37651963

RESUMO

Polyetheretherketone (PEEK) has emerged as a highly promising orthopedic implantation material due to its elastic modulus which is comparable to that of natural bone. This polymer exhibits impressive properties for bone implantation such as corrosion resistance, fatigue resistance, self-lubrication and chemical stability. Significantly, compared to metal-based implants, PEEK implants have mechanical properties that are closer to natural bone, which can mitigate the "stress shielding" effect in bone implantation. Nevertheless, PEEK is incapable of inducing osteogenesis due to its bio-inert molecular structure, thereby hindering the osseointegration process. To optimize the clinical application of PEEK, researchers have been working on promoting its bioactivity and endowing this polymer with beneficial properties, such as antibacterial, anti-inflammatory, anti-tumor, and angiogenesis-promoting capabilities. Considering the significant growth of research on PEEK implants over the past 5 years, this review aims to present a timely update on PEEK's modification methods. By highlighting the latest advancements in PEEK modification, we hope to provide guidance and inspiration for researchers in developing the next generation bone implants and optimizing their clinical applications.


Assuntos
Polietilenoglicóis , Polímeros , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Benzofenonas , Cetonas/uso terapêutico , Cetonas/química , Cetonas/farmacologia
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