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1.
Niger J Clin Pract ; 27(3): 368-375, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38528358

RESUMEN

BACKROUND: The evolution of restorative materials in prosthodontics has led to the emergence of indirect composite resins, including ceromers, as alternatives to traditional metal-ceramic restorations. However, research gaps exist regarding the impact of ageing protocols on the bond strength of ceromer composites to different metal substructures, necessitating further investigation in this area. AIM: This study aimed to determine the effect of five different ageing protocols on the shear bond strength (SBS) of ceromer indirect composites on two different substructures. METHODS: In this in vitro study, 120 metallic discs (10 × 2 mm) were cast from cobalt-chromium (Co-Cr) alloy (n = 60) and spark erosion treated from grade V titanium (n = 60). Each sample was sandblasted. The M.L. primer (Shofu, Germany) and layers of opaque were applied to the surface following the manufacturer's instructions. A special jig (6 × 2 mm) was placed on each disc. The ceromer was condensed in it and light-cured separately for 90 s. Following polishing, specimens were separated into five ageing groups: distilled water (as a control), thermal cycling, tea, coffee, and gastric acid immersion. All samples were placed in 37°C incubation for 28 days for distilled water, coffee, and tea, and 7 days for gastric acid immersion and thermal cycling for 5000 cycles (5-55°C). A universal test machine was used to measure the SBS. The samples were evaluated for failure modes using stereomicroscopy. Data were analyzed using one-way analysis of variance (ANOVA) (P < 0.05). RESULTS: According to one-way ANOVA, the mean SBS (MPa) between the two groups was compared in each ageing protocol, and there were no significant differences between the Co-Cr-C and Ti-C groups (P > 0.05). The most frequent mode of failure in all groups was mixed. CONCLUSIONS: Applying the ageing protocols, the type of substructure material had no significant effect on the SBS of the ceromer indirect composite except for tea immersion.


Asunto(s)
Café , Recubrimiento Dental Adhesivo , Metacrilatos , Humanos , Propiedades de Superficie , Resinas Compuestas/química , Cerámica , Aleaciones de Cromo/química , Agua/química , , Ensayo de Materiales , Resistencia al Corte , Análisis del Estrés Dental
2.
Adv Sci (Weinh) ; 11(12): e2305682, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38225752

RESUMEN

There are no Food and Drug Administration-approved drugs for treating noise-induced hearing loss (NIHL), reflecting the absence of clear specific therapeutic targets and effective delivery strategies. Noise trauma is demonstrated results in nicotinamide adenine dinucleotide (NAD+) downregulation and mitochondrial dysfunction in cochlear hair cells (HCs) and spiral ganglion neurons (SGNs) in mice, and NAD+ boosted by nicotinamide (NAM) supplementation maintains cochlear mitochondrial homeostasis and prevents neuroexcitatory toxic injury in vitro and ex vivo, also significantly ameliorated NIHL in vivo. To tackle the limited drug delivery efficiency due to sophisticated anatomical barriers and unique clearance pathway in ear, personalized NAM-encapsulated porous gelatin methacryloyl (PGMA@NAM) are developed based on anatomy topography of murine temporal bone by micro-computed tomography and reconstruction of round window (RW) niche, realizing hydrogel in situ implantation completely, NAM sustained-release and long-term auditory preservation in mice. This study strongly supports personalized PGMA@NAM as NIHL protection drug with effective inner ear delivery, providing new inspiration for drug-based treatment of NIHL.


Asunto(s)
Gelatina , Pérdida Auditiva Provocada por Ruido , Metacrilatos , Ratones , Animales , Pérdida Auditiva Provocada por Ruido/tratamiento farmacológico , Pérdida Auditiva Provocada por Ruido/prevención & control , Niacinamida/uso terapéutico , NAD , Preparaciones de Acción Retardada/uso terapéutico , Porosidad , Microtomografía por Rayos X
3.
Int Orthod ; 22(1): 100822, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37992472

RESUMEN

PURPOSE: The objective of this study was to compare the shear bond strengths of orthodontic brackets bonded to translucent dental zirconia samples which are anatomically accurate and treated with various surface treatments. METHODS: This in vitro study included 156 samples from 3 brands of high-translucent zirconia split into a control group and 4 surface treatment groups: 9.6% hydrofluoric acid etching, 50-micron aluminium oxide particle air abrasion, and 30-micron tribochemical silica coating (TBS) particle air abrasion with and without silane application. After surface treatment, all groups were primed with a 10-MDP primer and bonded to metal orthodontic brackets. Shear bond strength (SBS) was tested and results were compared between all groups. Data analysis consisted of a balanced two-factor factorial ANOVA, a Shapiro-Wilks test, and a non-parametric permutation test. The significance level was set at 0.05. RESULTS: Among all surface treatments, aluminium oxide particle abrasion produced significantly higher SBS (P≤0.002). Lava™ Plus zirconia samples had significantly higher SBS than Cercon® samples (P<0.0001). TBS surface treatment produced significantly higher SBS on Lava™ Plus samples than it did on the other zirconia brands (P=0.032). CONCLUSIONS: This study indicated that mechanical abrasion using aluminium oxide in combination with a 10-MDP primer creates a higher SBS to high-translucent zirconia than the bond created by tribochemical silica coating. Also, there was no significant difference in ARI regardless of zirconia brand or surface preparation.


Asunto(s)
Recubrimiento Dental Adhesivo , Metacrilatos , Soportes Ortodóncicos , Circonio , Humanos , Cementos de Resina/química , Abrasión Dental por Aire , Propiedades de Superficie , Resistencia al Corte , Dióxido de Silicio/química , Óxido de Aluminio/química , Ensayo de Materiales , Análisis del Estrés Dental
4.
Photobiomodul Photomed Laser Surg ; 41(10): 576-582, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37870415

RESUMEN

Objective: Assessment of post surface conditioners [sulfuric acid (SA), Rose Bengal (RB), and sandblasting (SB)] and different luting cements [methyl methacrylate (MMA)-based cement and composite-based cement] on pushout bond strength (PBS) of poly-ether ether-ketone (PEEK) post bonded to canal dentin. Materials and methods: Endodontic treatment was performed on 120 single-rooted human premolar teeth. The preparation of the post space was performed and 4 mm of gutta-percha was retained in the apical region of the root. One hundred and twenty PEEK posts were fabricated from a PEEK blank utilizing a Computer aided design-Computer aided manufacture (CAD-CAM) system. The PEEK posts were allocated randomly into four groups based on post surface conditioning (n = 30). Group A: SA, Group B: RB, Group C: SB, and Group D: No conditioning (NC). Each group was further divided into two subgroups based on the luting cement used for bonding (n = 15). Group A1, B1, C1, and D1 specimens were cemented using composite-based resin cement. However, Group A2, B2, C2, and D2 posts were luted with MMA-based resin cement. PBS assessment using a universal testing machine was performed. Failure modes were analyzed under a stereomicroscope. The data relating to the effects of surface treatment and luting types of cement were analyzed using one-way analysis of variance (ANOVA) and Tukey's post hoc test (p = 0.05). Results: Coronal section of Group B2: RB+Super-Bond C&B [9.61 ± 0.75 megapascals (MPa)] displayed the highest bond scores of PEEK after root dentin. Whereas it was also discovered that Group D1: NC+Panavia®V5 (2.05 ± 0.72 MPa) presented the lowest PBS scores. Intergroup comparison analysis revealed that Group A2: SA+Super-Bond C&B and Group B2: RB+Super-Bond C&B displayed no significant difference in their bond scores. Conclusions: RB and SA possess the potential to be used as a PEEK post conditioner. MMA-based cement displayed better performance than composite-based cement.


Asunto(s)
Fotoquimioterapia , Cementos de Resina , Humanos , Resinas Compuestas/química , Dentina , Éter , Cetonas , Metacrilatos/química , Metilmetacrilato , Cementos de Resina/química , Rosa Bengala
5.
Molecules ; 28(6)2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36985769

RESUMEN

Herein, we describe a one-step method for synthesizing cationic acrylate-based core-shell latex (CACS latex), which is used to prepare architectural coatings with excellent antimicrobial properties. Firstly, a polymerizable water-soluble quaternary ammonium salt (QAS-BN) was synthesized using 2-(Dimethylamine) ethyl methacrylate (DMAEMA) and benzyl bromide by the Hoffman alkylation reaction. Then QAS-BN, butyl acrylate (BA), methyl methacrylate (MMA), and vinyltriethoxysilane (VTES) as reactants and 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AIBA) as a water-soluble initiator were used to synthesize the CACS latex. The effect of the QAS-BN dosage on the properties of the emulsion and latex film was systematically investigated. The TGA results showed that using QAS-BN reduced the latex film's initial degradation temperature but improved its thermal stability. In the transmission electron microscopy (TEM) photographs, the self-stratification of latex particles with a high dosage of QAS-BN was observed, forming a core-shell structure of latex particles. The DSC, TGA, XPS, SEM, and performance tests confirmed the core-shell structure of the latex particles. The relationship between the formation of the core-shell structure and the content of QAS-BN was proved. The formation of the core-shell structure was due to the preferential reaction of water-soluble monomers in the aqueous phase, which led to the aggregation of hydrophilic groups, resulting in the formation of soft-core and hard-shell latex particles. However, the water resistance of the films formed by CACS latex was greatly reduced. We introduced a p-chloromethyl styrene and n-hexane diamine (p-CMS/EDA) crosslinking system, effectively improving the water resistance in this study. Finally, the antimicrobial coating was prepared with a CACS emulsion of 7 wt.% QAS-BN and 2 wt.% p-CMS/EDA. The antibacterial activity rates of this antimicrobial coating against E. coli and S. aureus were 99.99%. The antiviral activity rates against H3N2, HCoV-229E, and EV71 were 99.4%, 99.2%, and 97.9%, respectively. This study provides a novel idea for the morphological design of latex particles. A new architectural coating with broad-spectrum antimicrobial properties was obtained, which has important public health and safety applications.


Asunto(s)
Antiinfecciosos , Escherichia coli , Emulsiones/química , Staphylococcus aureus , Antiinfecciosos/farmacología , Antiinfecciosos/química , Metacrilatos/farmacología , Agua/química
6.
Molecules ; 28(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36903579

RESUMEN

The visualization of organs and tissues using 31P magnetic resonance (MR) imaging represents an immense challenge. This is largely due to the lack of sensitive biocompatible probes required to deliver a high-intensity MR signal that can be distinguished from the natural biological background. Synthetic water-soluble phosphorus-containing polymers appear to be suitable materials for this purpose due to their adjustable chain architecture, low toxicity, and favorable pharmacokinetics. In this work, we carried out a controlled synthesis, and compared the MR properties, of several probes consisting of highly hydrophilic phosphopolymers differing in composition, structure, and molecular weight. Based on our phantom experiments, all probes with a molecular weight of ~3-400 kg·mol-1, including linear polymers based on poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), poly(ethyl ethylenephosphate) (PEEP), and poly[bis(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)]phosphazene (PMEEEP) as well as star-shaped copolymers composed of PMPC arms grafted onto poly(amidoamine) dendrimer (PAMAM-g-PMPC) or cyclotriphosphazene-derived cores (CTP-g-PMPC), were readily detected using a 4.7 T MR scanner. The highest signal-to-noise ratio was achieved by the linear polymers PMPC (210) and PMEEEP (62) followed by the star polymers CTP-g-PMPC (56) and PAMAM-g-PMPC (44). The 31P T1 and T2 relaxation times for these phosphopolymers were also favorable, ranging between 1078 and 2368 and 30 and 171 ms, respectively. We contend that select phosphopolymers are suitable for use as sensitive 31P MR probes for biomedical applications.


Asunto(s)
Fósforo , Polímeros , Polímeros/química , Metacrilatos/química , Micelas , Fosforilcolina/química , Espectroscopía de Resonancia Magnética , Materiales Biocompatibles/química , Ácidos Polimetacrílicos/química , Propiedades de Superficie
7.
J Prosthodont Res ; 67(1): 150-156, 2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-35569998

RESUMEN

PURPOSE: To clarify the effect of a multi-purpose primer combining several functional monomers on two prosthodontic materials (cast titanium and a gold alloy) after airborne-particle abrasion. METHODS: Disk-shaped adherends were prepared from cast titanium (CP Titanium JIS2) and a gold alloy (Casting Gold M.C. Type IV). A silane-containing two-liquid primer (M&C primer (MC)) and two silane-free single-liquid primers (Alloy Primer (AP) and V-Primer (VP)) were used as surface-treatment agents. The shear bond strengths were determined before and after thermocycling to evaluate the adhesive durability, and the results were compared using a non-parametric statistical analysis. The effect of airborne-particle abrasion with alumina on the titanium surface was analyzed by X-ray photoelectron spectroscopy (XPS). RESULTS: There was no significant difference in bond strength between the MC and AP before and after thermocycling, whereas VP showed significantly lower values. XPS revealed that the titanium acquired hydrophilic properties after the airborne-particle abrasion. CONCLUSIONS: The novelty of this study is that it shows that the presence/absence of the silane had no effect on the bonding of cast titanium with an acrylic resin. The study also showed that the multi-purpose primer can be used without any problems with both cast titanium and gold alloy, in combination with airborne-particle abrasion with alumina.


Asunto(s)
Resinas Acrílicas , Recubrimiento Dental Adhesivo , Resinas Acrílicas/química , Aleaciones de Oro/química , Titanio/química , Metacrilatos/química , Resistencia al Corte , Óxido de Aluminio/química , Ensayo de Materiales , Cementos de Resina/química , Propiedades de Superficie
8.
ACS Appl Mater Interfaces ; 14(45): 50601-50615, 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36335599

RESUMEN

The unique tumor microenvironment (TME) characteristic of severe hypoxia, overexpressed intracellular glutathione (GSH), and elevated hydrogen peroxide (H2O2) concentration limit the anticancer effect by monotherapy. In this report, glucose oxidase (GOx)-encapsulated mesoporous hollow Co9S8 nanoreactors are constructed with the coverage of polyphenol diblock polymers containing poly(oligo(ethylene glycol) methacrylate) and dopamine moieties containing methacrylate polymeric block, which are termed as GOx@PCoS. After intravenous injection, tumor accumulation, and cellular uptake, GOx@PCoS deplete GSH by Co3+ ions. GOx inside the nanoreactors produce H2O2 via oxidation of glucose to enhance •OH-based chemodynamic therapy (CDT) through the Fenton-like reaction under the catalysis of Co2+. Moreover, Co3+ ions possess catalase activity to catalyze production of O2 from H2O2 to relieve tumor hypoxia. Upon 808 nm laser irradiation, GOx@PCoS exhibit photothermal and photodynamic effects with a high photothermal conversion efficiency (45.06%) and generation capacity of the toxic superoxide anion (•O2-) for photothermal therapy (PTT) and photodynamic therapy (PDT). The synergetic antitumor effects can be realized by GSH depletion, starvation, and combined CDT, PTT, and PDT with enhanced efficacy. Notably, GOx@PCoS can also be used as a magnetic resonance imaging (MRI) contrast agent to monitor the antitumor performance. Thus, GOx@PCoS show great potentials to effectively modulate TME and perform synergistic multimodal therapy.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Terapia Fototérmica , Peróxido de Hidrógeno , Línea Celular Tumoral , Microambiente Tumoral , Glutatión , Glucosa Oxidasa , Polímeros , Metacrilatos , Nanotecnología
9.
ACS Appl Mater Interfaces ; 14(40): 45178-45188, 2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36178205

RESUMEN

Noninvasive photothermal therapy (PTT) is an emerging strategy for eliminating multidrug-resistant (MDR) bacteria that achieve sterilization by generating temperatures above 50 °C; however, such a high temperature also causes collateral damage to healthy tissues. In this study, we developed a low-temperature PTT based on borneol-containing polymer-modified MXene nanosheets (BPM) with bacteria-targeting capabilities. BPM was fabricated through the electrostatic coassembly of negatively charged two-dimensional MXene nanosheets (2DM) and positively charged quaternized α-(+)-borneol-poly(N,N-dimethyl ethyl methacrylate) (BPQ) polymers. Integrating BPQ with 2DM improved the stability of 2DM in physiological environments and enabled the bacterial membrane to be targeted due to the presence of a borneol group and the partially positive charge of BPQ. With the aid of near-infrared irradiation, BPM was able to effectively eliminate methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli) through targeted photothermal hyperthermia. More importantly, BPM effectively eradicated more than 99.999% (>5 orders of magnitude) of MRSA by localized heating at a temperature that is safe for the human body (≤40 °C). Together, these findings suggest that BPM has good biocompatibility and that membrane-targeting low-temperature PTT could have great therapeutic potential against MDR infections.


Asunto(s)
Hipertermia Inducida , Staphylococcus aureus Resistente a Meticilina , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Canfanos , Escherichia coli , Humanos , Hipertermia Inducida/métodos , Metacrilatos/farmacología , Terapia Fototérmica , Polímeros/farmacología , Temperatura
10.
Biomacromolecules ; 23(10): 4308-4317, 2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36146942

RESUMEN

As a class of biocompatible and biodegradable naturally derived nanomaterials, cellulose nanocrystals (CNCs) with diverse surface functionalization have aroused considerable attention for a range of biomedical applications in drug or gene delivery, as a fluorescent nanoprobe, in cancer targeting, and in photothermal cancer therapy, among others. Herein, we construct the copolymer-functionalized CNCs as a pH- and near-infrared (NIR)-triggered drug carrier for simultaneous photothermal therapy and chemotherapy of cancer cells. Poly(ε-caprolactone)-b-poly(2-(dimethylamino)ethyl methacrylate) (PCL-b-PDMAEMA) was conjugated onto the surface of CNCs through ring-opening polymerization, followed by activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP). The resultant CNC-based drug carrier can encapsulate doxorubicin (DOX) as a therapeutic agent and indocyanine green (ICG) as an NIR dye in the PCL core and the PDMAEMA shell, respectively, via hydrophobic and electrostatic interactions. In addition to the intrinsic pH response, the release profile of DOX can also be controlled by the duration of laser irradiation due to collapse of the crystal structure of the PCL domain with the increase of temperature induced by photothermal conversion. The drug carrier can exhibit enhanced cytotoxicity toward HepG2, human hepatocyte carcinoma, cells upon laser irradiation, which can be attributed to the synergistic effect arising from NIR-triggered burst release of DOX and photothermal heating. The rod-like morphology of the CNC-based drug carrier may help accelerate the endocytosis in cell membranes compared with its common spherical counterpart. Based on the abovementioned advantages, copolymer-functionalized CNCs can serve as a promising candidate for effective cancer treatment.


Asunto(s)
Nanopartículas , Neoplasias , Celulosa/metabolismo , Doxorrubicina/química , Portadores de Fármacos , Liberación de Fármacos , Humanos , Concentración de Iones de Hidrógeno , Verde de Indocianina/química , Verde de Indocianina/farmacología , Metacrilatos , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Nylons , Fototerapia , Terapia Fototérmica , Polímeros/metabolismo
11.
BMC Oral Health ; 22(1): 430, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-36167560

RESUMEN

BACKGROUND: The blending ability of universal shade composites and their stability in the oral environment are of great concern in restoring anterior teeth. This study aims to evaluate and compare the color stability and surface roughness of two single-shade composite restorations, ormocer-based composite (OBC) and methacrylate resin-based composite (RBC), after storing them in different staining media. MATERIALS AND METHODS: In this study, two universal shade composite restorative materials were tested: a nanohybrid OBC (Admira fusion X-tra, Voco) and a supra-nanofilled RBC (Omnichroma, Toukyama). In total, 60 cylindrical centralized cavities (diameter: 5 mm, depth: 2 mm) were prepared in sound extracted-human central incisors and divided into two equal groups according to the restorative material used (n = 30). According to the storage media, the teeth of each group were divided into three subgroups (n = 10): artificial saliva, black tea, and cola. The restoration color was evaluated for all teeth at baseline and after four weeks of storage. The color stability (∆E) was measured using a reflective spectrophotometer (X-Rite, model RM200QC, Neu-Isenburg, Germany). The surface roughness (Ra) was evaluated using three-dimensional optical profilometry (Wyko, Model NT 1100, Veeco, Tucson, USA). Additionally, the extracted data were analyzed using two-way analysis of variance (ANOVA), one-way ANOVA and Student's t-test. RESULTS: In the baseline evaluation, there were no statistically significant differences with respect to color matching or surface roughness results between the two studied restorative materials. However, the differences were statistically significant after storing them in different media. CONCLUSION: Universal composites showed satisfactory color matching with different teeth colors and accepted surface smoothness, whereas the aging procedure exerted a negative effect on their color stability and surface characteristics.


Asunto(s)
Resinas Compuestas , Restauración Dental Permanente , Color , Materiales Dentales , Restauración Dental Permanente/métodos , Humanos , Ensayo de Materiales , Metacrilatos , Cerámicas Modificadas Orgánicamente , Saliva Artificial , Propiedades de Superficie ,
12.
Radiat Res ; 198(4): 357-367, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35913891

RESUMEN

The release of actinides into the environment represents a significant potential public health concern. Chelation therapy utilizing diethylenetriamine pentaacetate (DTPA) is a U.S. Food and Drug Administration (FDA)-approved therapy capable of mitigating the deposition of some absorbed actinides in the body. However, the pharmacokinetic profile of DTPA is not ideal for prophylactic applications. In this study, we examine the incorporation of DTPA into a HPMA copolymer (P-DTPA) to investigate if the enhanced blood circulation time can offer superior prophylactic protection and of improving in vivo radiometal decorporation. Utilizing lutetium-177 (177Lu) as an actinide model, the performance of P-DTPA and DTPA (control) were evaluated using selectivity studies in the presence of competing biological metals, chelation and stability assays in human serum and cytotoxicity studies using human umbilical vein endothelial cells (HUVEC). The in vivo decorporation efficiency of P-DTPA relative to DTPA and untreated controls was also evaluated over two weeks in CF-1 mice. In the experimental groups, the mice were prophylactically treated with P-DTPA or DTPA (30 µmol/kg) 6 or 24 h prior to 177LuCl3 administration. The in vitro results reveal that P-DTPA gives efficient complexation yields relative to DTPA with a tolerable cytotoxicity profile and good serum stability. The in vivo decorporation studies demonstrated enhanced total excretion of the 177Lu using P-DTPA compared to DTPA in both the 6 and 24 h prophylactic treatment study arms. This enhanced decorporation effect is certainly attributable to the expected prolonged biological half-life of DTPA when grafted to the HPMA polymer.


Asunto(s)
Elementos de Series Actinoides , Plutonio , Animales , Quelantes/farmacología , Descontaminación/métodos , Células Endoteliales , Humanos , Metacrilatos , Ratones , Ácido Pentético/farmacología , Plutonio/toxicidad , Poliaminas , Polímeros
13.
Int J Biol Macromol ; 218: 488-505, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-35878666

RESUMEN

A new kind of Camellia sinensis-loaded nanocomposite hydrogel based on modified gelatin/iron-metal-organic framework was developed as an antibacterial wound dressing. Gelatin as a biocompatible natural polymer was modified with methacrylate anhydride to produce gelatin methacrylate. Thereafter, acrylic acid and acrylamide were grafted on gelatin methacrylate during an aqueous polymerization process. To enhance the porosity, mechanical strength, and drug loading capability of the hydrogel and reduce its toxicity, iron- based metal-organic framework was incorporated within the hydrogel. To add more functionality to the final wound dressing, Camellia sinensis, an antibacterial herbal drug was loaded on the hydrogel. The structural and chemical properties of prepared nanocomposite hydrogel were investigated by FTIR, XRD, SEM, and TGA techniques. The incorporation of iron-based metal-organic framework within the hydrogel matrix led to an increase in its water absorption value from 400.10 to 547.96 (g/g). The release study of Camellia sinensis (CS) extract from the prepared nanocomposite hydrogel exhibited a sustained release manner. The antibacterial test revealed the nanocomposite hydrogel contain extract has an effective antibacterial function against "Bacillus serous", "Staphylococcus aureus", "Streptococcus mutans"," Escherichia coli", "Klebsiella pneumoniae", and "Pseudomonas aeruginosa" bacteria. Therefore, the synthesized nanocomposite is a good candidate as an antibacterial hydrogel wound dressing. .


Asunto(s)
Camellia sinensis , Estructuras Metalorgánicas , Antibacterianos/química , Antibacterianos/farmacología , Vendajes , Escherichia coli , Gelatina/química , Hidrogeles/química , Hidrogeles/farmacología , Hierro/farmacología , Estructuras Metalorgánicas/farmacología , Metacrilatos/farmacología , Nanogeles
14.
Artículo en Inglés | MEDLINE | ID: mdl-35662876

RESUMEN

Graphene oxide (GO) was introduced into a monolithic column and a network porous poly (GO-co-TAIC-co-MMA) monolith was prepared by redox polymerization. The internal morphology and pore size distribution of the polymer were observed by scanning electron microscopy, and the nitrogen adsorption-desorption and mercury intrusion methods. After optimization, 8 kinds of aromatic compounds were effectively separated in 5 min, and the theoretical plates number of the monolithic column exceeded 33, 070 plates m-1. Five kinds of main ingredients were separated from the traditional Chinese medicine (Schisandra) ingredients and 26 peaks were successfully separated from the fermentation broth containing natural lipopeptide antibiotics. The addition of GO material enhanced the interaction between the compound and the monolithic column, increased the binding sites, improved the uniformity of the internal pore structure of the monolithic column, and improved the separation performance of the monolith. Methodologic validation of five ingredients in Schisandra showed that the correlation coefficients of the linear regressions were in the range of 0.9987-0.9997. The intra- and inter-day values of the relative standard deviation for precision were in the range of 0.6-4.1% and 1.1-4.8%, respectively. The values of accuracy (expressed as recovery) were in the range of 97.7-103.2%, 100.5-105.0%, 98.2-101.8%, 101.3-104.1%, and 101.2-103.3% for the 5 ingredients in order. In terms of the relative standard deviation of the retention time, the reproducibility of the monolithic column M1 was <3.7%. The monolithic column based on GO has great potential in chromatographic separation.


Asunto(s)
Lipopéptidos , Metacrilatos , Antibacterianos , Cromatografía Líquida de Alta Presión/métodos , Grafito , Metacrilatos/química , Porosidad , Reproducibilidad de los Resultados
15.
Int J Biol Macromol ; 208: 530-543, 2022 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-35346679

RESUMEN

Frequent dressing changes can result in secondary wound damage. Therefore, it is of great significance to construct a wound dressing that can be used for a long time without changing. Here, a double-network hydrogel was synthesized through hydrogen bonding interactions of tea polyphenol (TP)/glycerol with photo-crosslinked N-acryloyl glycinamide (NAGA), gelatin methacrylate (GelMA), and nanoclay hydrogel. The glycerol/water solvent slowed the diffusion of TP into the NAGA/GelMA/Laponite (NGL)hydrogel, thereby avoiding excessive crosslinking, and forming a uniform network. The hydrogel exhibited excellent water retention (84% within 28 days). Additionally, due to the hygroscopicity of glycerol, the hydrogel's mechanical strength (0.73-1.14 MPa) and tensile strain (207%-353%) increased further after 14 days in an open environment. Additionally, the hydrogel exhibited superior anti-ultraviolet and antioxidant properties, which effectively alleviated the wound site's oxidative stress and accelerated wound healing. Moreover, antibacterial activity was observed against both E. coli and S. aureus in the hydrogel wound dressing. Thus, by promoting wound closure, angiogenesis and collagen deposition, the double-network NGLG20/TG hydrogel dressing can successfully accelerate wound healing. The multifunctional double-network hydrogel, therefore, shows immense potential as an ideal candidate for wound dressings because it is long-lasting and prevents secondary damage caused by frequent dressing changes.


Asunto(s)
Antioxidantes , Hidrogeles , Antibacterianos/farmacología , Antioxidantes/farmacología , Escherichia coli , Gelatina , Glicerol , Hidrogeles/farmacología , Metacrilatos , Polifenoles/farmacología , Staphylococcus aureus , , Agua , Cicatrización de Heridas
16.
Molecules ; 27(3)2022 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-35164104

RESUMEN

Coffee, the most popular beverage in the 21st century society, was tested as a reaction environment for activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) without an additional reducing agent. Two blends were selected: pure Arabica beans and a proportional blend of Arabica and Robusta beans. The use of the solution received from the mixture with Robusta obtained a high molecular weight polymer product in a short time while maintaining a controlled structure of the synthesized product. Various monomers with hydrophilic characteristics, i.e., 2-(dimethylamino)ethyl methacrylate (DMAEMA), oligo(ethylene glycol) methyl ether methacrylate (OEGMA500), and glycidyl methacrylate (GMA), were polymerized. The proposed concept was carried out at different concentrations of coffee grounds, followed by the determination of the molar concentration of caffeine in applied beverages using DPV and HPLC techniques.


Asunto(s)
Café/química , Metacrilatos/química , Polimerizacion , Ácidos Polimetacrílicos , Ácidos Polimetacrílicos/síntesis química , Ácidos Polimetacrílicos/química
17.
Fitoterapia ; 157: 105119, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34979257

RESUMEN

Four rare isotachin-derived, isotachins E-H (1-4), together with two known biogenetically related isotachin derivatives (5 and 6) were isolated from the solid rice fermentation of a fungus Penicillium tanzanicum ZY-5 obtained from a medicinal plant Dasymaschalon rostratum collected from the Changjiang County, Hainan Province, China. Their structures were elucidated using comprehensive spectroscopic methods. The single-crystal X-ray diffraction of compound 5 was determined. Compounds 1-4 have a trans-3-(methylthio)-acrylic acid fragment, which are rare in nature. The inhibitory activities of all compounds against the nitric oxide (NO) production induced by lipopolysaccharide in mouse macrophage RAW 264.7 cells in vitro were evaluated.


Asunto(s)
Annonaceae/microbiología , Metacrilatos/química , Penicillium/química , Animales , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Cristalografía por Rayos X , Concentración 50 Inhibidora , Espectroscopía de Resonancia Magnética , Metacrilatos/aislamiento & purificación , Ratones , Estructura Molecular , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/metabolismo , Penicillium/aislamiento & purificación , Células RAW 264.7 , Espectrofotometría Infrarroja
18.
J Dent Res ; 101(7): 769-776, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35081830

RESUMEN

Durable resin-ceramic adhesion may influence the clinical success of ceramic restorations, which has been one of the challenging issues in dentistry. The present study assessed the bond strength and chemical interaction of 10-methacryloxydecyl dihydrogen phosphate (MDP), MDP+silane, and MDP-salt primers to alumina-blasted zirconia ceramic by tensile bond strength test, surface elemental composition with x-ray photoelectron spectroscopy analysis, contact angle measurement, surface morphology with scanning electron microscopy, and surface topography with 3-dimensional confocal laser scanning microscope analyses. MDP-salt showed the highest tensile bond strength before and after thermocycling when compared with MDP and MDP+silane (P < 0.05). The measured contact angle values differed significantly (P < 0.001) in the order of MDP-salt > control (no chemical pretreatment) > MDP+silane > MDP. There was no difference in surface roughness (P = 0.317) and surface topography among all tested groups. Zirconia treated with MDP-salt showed phosphorus peaks in addition to zirconia and alumina peaks. MDP-salt has zirconia priming properties, which improves bonding performance to resin cement.


Asunto(s)
Recubrimiento Dental Adhesivo , Sales (Química) , Óxido de Aluminio , Recubrimiento Dental Adhesivo/métodos , Ensayo de Materiales , Metacrilatos/química , Cementos de Resina/química , Resistencia al Corte , Silanos/química , Propiedades de Superficie , Circonio/química
19.
Mater Sci Eng C Mater Biol Appl ; 129: 112367, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34579886

RESUMEN

We developed a hemocompatible, bio-inspired, multivalent, polymeric-chelating assembly based on the poly(2-methacryloyloxyethyl phosphorylcholine)-b-poly(serinyl acrylate) (PMPC-b-PserA) zwitterionic diblock copolymer. Functional PMPC-b-PserA was synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization to catch and encapsulate free copper ions (Cu2+) in a solution. PMPC with an identical polar group to phospholipids exhibits high hydrophilicity and fouling resistance against non-specific adsorption, and inertness to the metal ions. On the other hand, PserA with pendant groups of amino acids possesses a strong capability to react with Cu2+ by coordination interaction. Therefore, when PMPC-b-PserA was brought into contact with Cu2+, a hydrophobic core with multiple coordination "bridges" between polymers and Cu2+ was formed, leading to self-assembly of core-shell polymer-metal nanoparticles. As a result, free Cu2+ ions can be removed from the solution to prevent damage to cells and tissues. The synthesis and chemical structure of PMPC-b-PserA were characterized, and the formation of self-assembled polymer-Cu2+ nanoparticles and colloidal stability were analyzed. More importantly, the detoxification of PMPC-b-PserA in presence of Cu2+ with fibroblast cells was demonstrated by increased cell viability >80%. In addition, the hemolysis, which occurred due to disruption of RBC membranes by free Cu2+, was effectively suppressed by adding PMPC-b-PserA. The bio-inspired and biocompatible chelating agent of PMPC-b-PserA provides a new treatment approach to encapsulate and detoxify heavy metals in complex media for chelation therapy.


Asunto(s)
Cobre , Hemólisis , Quelantes/farmacología , Humanos , Metacrilatos , Micelas , Fosforilcolina/farmacología , Polímeros , Ácidos Polimetacrílicos
20.
ACS Appl Mater Interfaces ; 13(33): 38979-38989, 2021 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-34433249

RESUMEN

Chronic infections caused by Pseudomonas aeruginosa pose severe threats to human health. Traditional antibiotic therapy has lost its total supremacy in this battle. Here, nanoplatforms activated by the clinical microenvironment are developed to treat P. aeruginosa infection on the basis of dynamic borate ester bonds. In this design, the nanoplatforms expose targeted groups for bacterial capture after activation by an acidic infection microenvironment, resulting in directional transport delivery of the payload to bacteria. Subsequently, the production of hyperpyrexia and reactive oxygen species enhances antibacterial efficacy without systemic toxicity. Such a formulation with a diameter less than 200 nm can eliminate biofilm up to 75%, downregulate the level of cytokines, and finally promote lung repair. Collectively, the biomimetic design with phototherapy killing capability has the potential to be an alternative strategy against chronic infections caused by P. aeruginosa.


Asunto(s)
Antibacterianos/química , Verde de Indocianina/química , Nanocápsulas/química , Fármacos Fotosensibilizantes/química , Polímeros/química , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/radioterapia , Células A549 , Animales , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Composición de Medicamentos , Liberación de Fármacos , Sinergismo Farmacológico , Humanos , Verde de Indocianina/farmacología , Rayos Infrarrojos , Masculino , Metacrilatos/química , Ratones Endogámicos BALB C , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Polietilenglicoles/química , Pseudomonas aeruginosa/efectos de los fármacos
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