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The present study elucidates the effectiveness of a molecularly imprinted polyacrylonitrile-imbued graphite-base electrode (MAN@G) for the selective detection of folic acid (FA) in food samples. The prime objective of the recognition and quantification of vitamin compounds like FA is the overall quality assessment of vegetables and fruits. The cost-effective, reproducible, and durable MAN@G electrode has been fabricated using acrylonitrile (AN) as the monomer and FA as the template over graphite-base. The characterization of the synthesized MAN@G electrode material has been accomplished by utilizing UV-visible (UV-vis) spectroscopy and scanning electron microscopy (SEM). A tri-electrode system based on differential pulse voltammetry (DPV) and cyclic voltammetry (CV) techniques was employed to explore the analytical performance of the synthesized electrode. Rigorous analyses divulged that a widespread linearity window could be exhibited by the electrode under an optimized experimental environment, ranging from 20 µM to 400 µM concentrations with an acceptable lower limit of detection (LOD) and limit of quantification (LOQ) of 18 nM, and 60 nM respectively. Additionally, this electrode exhibits high reproducibility, good stability, and high repeatability, with RSD values of 1.72 %, 1.32 %, and 1.19 %, respectively. The detection efficacy of the proposed electrode has been further examined in food extracts, namely orange, spinach, papaya, soybean, and cooked rice, which endorsed high accuracy compared to the high-performance liquid chromatography (HPLC) method. Moreover, the statistical results obtained from the t-test analysis were also satisfactory for the FA concentrations present in those five samples.
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Resinas Acrílicas , Técnicas Electroquímicas , Electrodos , Ácido Fólico , Grafito , Grafito/química , Resinas Acrílicas/química , Ácido Fólico/análisis , Impresión Molecular , Límite de Detección , Análisis de los Alimentos/métodos , Polímeros Impresos Molecularmente/química , Frutas/químicaRESUMEN
Background There are insufficient data comparing resorbable microspheres (RMs) with permanent trisacryl gelatin microspheres (TAGMs) for uterine artery embolization (UAE). Purpose To compare therapeutic efficacy and clinical outcomes in participants with symptomatic fibroids after UAE with RMs or TAGMs. Materials and Methods This randomized controlled trial included participants undergoing UAE for symptomatic fibroids at a single institution (from May 2021 to May 2023). Participants were randomized one-to-one to undergo UAE with either RMs or TAGMs. Numeric rating scale pain scores and cumulative fentanyl consumption were assessed for 24 hours after undergoing UAE. Anti-Mullerian hormone was measured to assess effects of UAE on ovarian function. MRI was performed before and 3 months after UAE to evaluate fibroid necrosis and uterine artery recanalization. Repeated variables such as pain were analyzed using Mann-Whitney U test with post hoc Bonferroni correction. Results Sixty female participants (mean age, 45.7 years ± 3.6 [SD]) completed the study, with 30 in each group. No evidence of a difference in pain scores was observed between groups (P > .99). Moreover, there was no evidence of a difference in the total fentanyl consumption at 24 hours after UAE between groups (median: RMs, 423 [IQR, 330-530] vs TAGMs, 562 [IQR, 437-780]; P = .15). Serum anti-Mullerian hormone 3 months after UAE showed no evidence of a difference between groups (RMs vs TAGMs, 0.71 ng/mL ± 0.73 vs 0.49 ng/mL ± 0.45, respectively; P = .09). No evidence of a difference in the rate of complete necrosis of the dominant fibroid was observed between groups (97% [29 of 30] for both groups; P > .99). The rate of uterine artery recanalization was higher in RM versus TAGM groups (70% [21 of 30] vs 17% [five of 30], respectively; P < .001). Conclusion UAE with RMs, compared with UAE with TAGMs, showed no evidence of a difference in terms of therapeutic effectiveness or postprocedural pain scores in participants with symptomatic fibroids. Clinical trial registration no. NCT05086770 © RSNA, 2024 See also the editorial by Spies in this issue.
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Resinas Acrílicas , Gelatina , Leiomioma , Embolización de la Arteria Uterina , Humanos , Femenino , Embolización de la Arteria Uterina/métodos , Gelatina/uso terapéutico , Persona de Mediana Edad , Leiomioma/terapia , Leiomioma/diagnóstico por imagen , Resinas Acrílicas/uso terapéutico , Adulto , Microesferas , Neoplasias Uterinas/terapia , Neoplasias Uterinas/diagnóstico por imagen , Resultado del Tratamiento , Dimensión del DolorRESUMEN
Drug treatment of glioblastoma, the most aggressive and widespread form of brain cancer, is complicated due to the difficulty of penetration of chemotherapeutic drugs through the blood-brain barrier (BBB). Moreover, with surgical removal of tumors, in 90 % of cases they reappear near the original focus. To solve this problem, we propose to use hydrogel based on cellulose nanocrystals grafted with poly(N-isopropylacrylamide) (CNC-g-PNIPAM) as a promising material for filling postoperative cavities in the brain with the release of antitumor drugs. The CNC-g-PNIPAM is formed by "grafting to" method for precise control of molecular weight and grafting density. This colloidal system is liquid under injection conditions (at r. t.) and turns into a gel at human body temperature (when filling the postoperative area). It was shown for the first time that due to the rod-shaped of CNC, the gel has a fibrillar structure and, thus, mechanical properties similar to those of brain tissue, including nonlinear mechanics (strain-stiffening and compression softening). The biocompatibility of the hydrogel with primary brain cells is demonstrated. In addition, the release of the antitumor drug paclitaxel from the hydrogel and its antitumor activity is shown. The resulting nanocolloid system provides an innovative alternative approach to filling postoperative cavities and can be used for postoperative treatment due to the programmable release of drugs, as well as for in vitro modeling of tumor interaction with the BBB affecting drug transport in the brain.
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Resinas Acrílicas , Materiales Biocompatibles , Celulosa , Hidrogeles , Nanopartículas , Celulosa/química , Nanopartículas/química , Resinas Acrílicas/química , Humanos , Animales , Materiales Biocompatibles/química , Hidrogeles/química , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Paclitaxel/química , Paclitaxel/farmacología , Paclitaxel/administración & dosificación , Temperatura , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Liberación de Fármacos , Barrera Hematoencefálica/metabolismoRESUMEN
The ability to transform matter between numerous physical states or shapes without wires or external devices is a major challenge for robotics and materials design. Organisms can transform their shapes using biomolecules carrying specific information and localize at sites where transitions occur. Here, we introduce gel automata, which likewise can transform between a large number of prescribed shapes in response to a combinatorial library of biomolecular instructions. Gel automata are centimeter-scale materials consisting of multiple micro-segments. A library of DNA activator sequences can each reversibly grow or shrink different micro-segments by polymerizing or depolymerizing within them. We develop DNA activator designs that maximize the extent of growth and shrinking, and a photolithography process for precisely fabricating gel automata with elaborate segmentation patterns. Guided by simulations of shape change and neural networks that evaluate gel automata designs, we create gel automata that reversibly transform between multiple, wholly distinct shapes: four different letters and every even or every odd numeral. The sequential and repeated metamorphosis of gel automata demonstrates how soft materials and robots can be digitally programmed and reprogrammed with information-bearing chemical signals.
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Resinas Acrílicas , ADN , Geles , Geles/química , ADN/química , Resinas Acrílicas/química , Redes Neurales de la Computación , Algoritmos , Fenómenos Químicos , Secuencia de BasesRESUMEN
Hydrogels are highly sought-after absorbent materials for absorbent pads; however, it is still challenging to achieve a satisfactory balance between mechanical performance, water absorption capacity, and active functionalities. In this work, we presented double-network hydrogels synthesized through acrylic acid (AA) polymerization in the presence of quaternized cellulose nanofibrils (QCNF) and Fe3+. Spectroscopic and microscopic analyses revealed that the combined QCNF and Fe3+ facilitated the formation of double-network hydrogels with combined chemical and physical crosslinking. The synergistic effect of QCNF and Fe3+ resulted in impressive mechanical properties, including tensile strength of 1.98 MPa, fracture elongation of 838.8 %, toughness of 7.47 MJ m-3, and elastic modulus of 0.35 MPa. In comparison to the single-network PAA hydrogel, the PAA/QCNF/Fe3+ (PQFe) hydrogels showed higher and relatively stable swelling ratios under varying pH levels and saline conditions. The PQFe hydrogels exhibited notable antioxidant activity, as evidenced by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and demonstrated effective antibacterial activity against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). These hydrogels show promising potential as an absorbent interlayer in absorbent pads for active food packaging.
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Resinas Acrílicas , Antibacterianos , Celulosa , Escherichia coli , Hidrogeles , Hierro , Nanofibras , Staphylococcus aureus , Resistencia a la Tracción , Hidrogeles/química , Hidrogeles/farmacología , Celulosa/química , Staphylococcus aureus/efectos de los fármacos , Resinas Acrílicas/química , Escherichia coli/efectos de los fármacos , Nanofibras/química , Hierro/química , Antibacterianos/farmacología , Antibacterianos/química , Antioxidantes/química , Antioxidantes/farmacología , Módulo de ElasticidadRESUMEN
The objective of the study was to develop a novel topical gel by mixing Potentilla tormentilla ethanolic extract, thermosensitive poloxamer 407, and carbomer 940 and evaluating its stability and rheological behavior. The irritation potential of the gel was evaluated in accordance with the Organization for Economic Cooperation and Development Guidelines 404. The potential anti-inflammatory effects of the developed gel were evaluated in vivo in rats using the carrageenan-induced paw edema test. Moreover, the in silico binding affinity for chlorogenic and ellagic acid, as dominant components in the extract, against cyclooxygenase (COX) 1 and 2 was also determined. Our findings suggest that the gel containing Potentilla tormentilla extract remained stable throughout the observation period, exhibited pseudoplastic behavior, and caused no irritation in rats, thus being considered safe for topical treatment. Additionally, the developed gel showed the capability to reduce rat paw edema, which highlights significant anti-inflammatory potential. In silico analysis revealed that chlorogenic and ellagic acid exhibited a reduced binding affinity against COX-1 but had a similar inhibitory effect on COX-2 as flurbiprofen, which was confirmed by molecular dynamics results. The study proposes the possible application of Potentilla tormentilla ethanolic extract gel for the alleviation of localized inflammatory diseases; however, future clinical evaluation is required.
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Antiinflamatorios , Ciclooxigenasa 1 , Edema , Extractos Vegetales , Potentilla , Animales , Potentilla/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Ratas , Antiinflamatorios/farmacología , Antiinflamatorios/química , Edema/tratamiento farmacológico , Edema/inducido químicamente , Masculino , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 1/química , Geles/química , Ácido Elágico/farmacología , Ácido Elágico/química , Ciclooxigenasa 2/metabolismo , Carragenina , Ratas Wistar , Poloxámero/química , Resinas Acrílicas/química , Ácido Clorogénico/química , Ácido Clorogénico/farmacologíaRESUMEN
The surface pre-reacted glass ionomer (S-PRG) filler is a type of bioactive functional glass that releases six different ions. This study examined the effects of the S-PRG filler eluate on Streptococcus mutans in the presence of sucrose. In a solution containing S. mutans, the concentrations of BO33-, Al3+, Sr2+, and F- were significantly higher in the presence of the S-PRG filler eluate than in its absence (p < 0.001). The concentrations of these ions further increased in the presence of sucrose. Additionally, the S-PRG filler eluate significantly reduced glucan formation by S. mutans (p < 0.001) and significantly increased the pH of the bacterial suspension (p < 0.001). Bioinformatic analyses revealed that the S-PRG filler eluate downregulated genes involved in purine biosynthesis (purC, purF, purL, purM, and purN) and upregulated genes involved in osmotic pressure (opuAa and opuAb). At a low pH (5.0), the S-PRG filler eluate completely inhibited the growth of S. mutans in the presence of sucrose and significantly increased the osmotic pressure of the bacterial suspension compared with the control (p < 0.001). These findings suggest that ions released from the S-PRG filler induce gene expression changes and exert an inhibitory effect on S. mutans in the presence of sucrose.
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Streptococcus mutans , Sacarosa , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/crecimiento & desarrollo , Sacarosa/farmacología , Sacarosa/química , Concentración de Iones de Hidrógeno , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Glucanos/farmacología , Glucanos/química , Propiedades de Superficie , Presión Osmótica/efectos de los fármacos , Resinas Acrílicas , Dióxido de SilicioRESUMEN
The application of biomaterials in bone regeneration is a prevalent clinical practice. However, its efficacy in elderly patients remains suboptimal, necessitating further advancements. While biomaterial properties are known to orchestrate macrophage (MΦ) polarization and local immune responses, the role of biomaterial cues, specifically stiffness, in directing the senescent macrophage (S-MΦ) is still poorly understood. This study aimed to elucidate the role of substrate stiffness in modulating the immunomodulatory properties of S-MΦ and their role in osteo-immunomodulation. Our results demonstrated that employing collagen-coated polyacrylamide hydrogels with varying stiffness values (18, 76, and 295 kPa) as model materials, the high-stiffness hydrogel (295 kPa) steered S-MΦs towards a pro-inflammatory M1 phenotype, while hydrogels with lower stiffness (18 and 76 kPa) promoted an anti-inflammatory M2 phenotype. The immune microenvironment created by S-MΦs promoted the bioactivities of senescent endothelial cells (S-ECs) and senescent bone marrow mesenchymal stem cells BMSCs (S-BMSCs). Furthermore, the M2 S-MΦs, particularly incubated on the 76 kPa hydrogel matrices, significantly enhanced the ability of angiogenesis of S-ECs and osteogenic differentiation of S-BMSCs, which are crucial and interrelated processes in bone healing. This modulation aided in reducing the accumulation of reactive oxygen species in S-ECs and S-BMSCs, thereby significantly contributing to the repair and regeneration of aged bone tissue.
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Regeneración Ósea , Hidrogeles , Inmunomodulación , Macrófagos , Células Madre Mesenquimatosas , Osteogénesis , Regeneración Ósea/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Hidrogeles/química , Osteogénesis/efectos de los fármacos , Células Madre Mesenquimatosas/inmunología , Animales , Senescencia Celular/efectos de los fármacos , Humanos , Diferenciación Celular , Neovascularización Fisiológica/efectos de los fármacos , Resinas Acrílicas/química , Resinas Acrílicas/farmacología , Materiales Biocompatibles/farmacología , Propiedades de Superficie , Colágeno/metabolismoRESUMEN
Despite decades of research and development, the optimal efficiency of slurry-packed HPLC columns is still hindered by inherent long-range flow heterogeneity from the wall to the central bulk region of these columns. Here, we show an example of how this issue can be addressed through the straightforward addition of a semidilute amount (500 ppm) of a large, flexible, synthetic polymer (18 MDa partially hydrolyzed polyacrylamide, HPAM) to the mobile phase (1% NaCl aqueous solution, hereafter referred to as "brine") during operation of a 4.6 mm × 300 mm column packed with 10µm BEHTM 125 Å particles. Addition of the polymer imparts elasticity to the mobile phase, causing the flow in the interparticle pore space to become unstable above a threshold flow rate. We verify the development of this elastic flow instability using pressure drop measurements of the friction factor versus Reynolds number. In prior work, we showed that this flow instability is characterized by large spatiotemporal fluctuations in the pore-scale flow velocities that may promote analyte dispersion across the column. Axial dispersion measurements of the quasi non-retained tracer thiourea confirm this possibility: they reveal that operating above the onset of the instability improves column efficiency by greater than 100%. These experiments thereby suggest that elastic flow instabilities can be harnessed to mitigate the negative impact of trans-column flow heterogeneities on the efficiency of slurry-packed HPLC columns. While this approach has its own inherent limitations and constraints, our results lay the groundwork for future targeted development of polymers that can impart elasticity when dissolved in commonly used liquid chromatography mobile phases, and can thereby generate elastic flow instabilities to help improve the resolution of HPLC columns.
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Resinas Acrílicas , Cromatografía Líquida de Alta Presión/métodos , Cinética , Resinas Acrílicas/química , ElasticidadRESUMEN
Recently, interest in tooth-colored fluoride-releasing dental materials has increased. Although physical and mechanical properties such as surface hardness, elastic modulus and surface roughness of the restorative materials have been investigated, the effect of different immersion media on these properties is still controversial. The aim of this study was to evaluate the nanohardness, elastic modulus and surface roughness of the fluoride release of tooth-colored restorative materials after immersion in acidic beverages. Prepared samples of three restorative materials (a highly viscous glass ionomer (EQUIA Forte; GC, Tokyo, Japan), a compomer (Dyract XP; Dentsply, Weybridge, UK), and a bioactive restorative material (Activa BioACTIVE; Pulpdent, MA, USA)) were randomly divided and immersed in distilled water, a cola and an orange juice for one week. The HYSITRON T1 950 TriboIndenter device (Hysitron, USA) with the Berkovich diamond indenter tip was used for all measurements. The nanohardness and elastic modulus of the samples were measured by applying a force of 6000 µN to five different points on the sample surface. Surface roughness measurements were evaluated on random samples by scanning five random 40 × 40 µm areas. The properties were measured at the initial and one week after immersion. The values of nanohardness, elastic modulus and surface roughness were tested for significant differences using a two-way analysis of variance (ANOVA) with repeated measures (p < 0.05). Tukey's honest significant difference (HSD) test was used for multiple comparisons. AB (Activa BioACTIVE) had the highest initial mean values for nanohardness. After post-immersion, the highest mean value for elastic modulus was the initial AB value. The lowest mean value for roughness of 100.36 nm was obtained for the initial DX (Dyract XP) measurement. Acidic beverages had a negative effect on the nanohardness, elastic modulus and surface roughness of the restorative materials.
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Bebidas Gaseosas , Módulo de Elasticidad , Fluoruros , Dureza , Ensayo de Materiales , Propiedades de Superficie , Fluoruros/química , Compómeros/química , Humanos , Materiales Dentales/química , Jugos de Frutas y Vegetales , Resinas Acrílicas/química , Restauración Dental Permanente/métodos , Agua/química , Cariostáticos/química , Cementos de Ionómero Vítreo/química , Citrus sinensis/química , Inmersión , Resinas Compuestas/química , Dióxido de SilicioRESUMEN
Polyacrylamide hydrogel mammoplasty is a simple and relatively affordable surgery. However, this procedure is associated with a significant frequency of late complications, prompting its suspension in 2006. Despite this, patients continue facing long-term consequences. These include hydrogel migration, changes in breast shape and volume, granulomas, fistulas, and abscess formation. The clinical case described here presents the surgical treatment after augmentation mammoplasty with polyacrylamide hydrogel performed 35 years ago.
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Resinas Acrílicas , Mamoplastia , Humanos , Femenino , Mamoplastia/métodos , Implantes de Mama/efectos adversos , Adulto , Persona de Mediana EdadRESUMEN
PURPOSE: This study aimed to evaluate the efficacy and safety following treatment with Bulkamid for stress urinary incontinence (SUI) or stress-predominant mixed urinary incontinence (MUI). METHODS: We retrospectively analyzed data of women diagnosed with SUI or stress-predominant MUI who underwent Bulkamid periurethral injection between November 2020 and January 2023 and completed 12 months of follow-up. The primary outcome of the study was to assess patient satisfaction, which was measured on a four-point scale, ranging from cured to worse, and through validated questionaries such as the International Consultation on Incontinence Questionnaire-short Form (ICIQ-UI SF) and Contilife Quality of Life questionnaire. RESULTS: Of the 70 patients included, 41 (59%) had MUI with predominant stress incontinence. Median age was 59 years (IQR 47-75), with a median BMI of 25 (18-40) and a median number of pregnancies of 2 (0-4). Forty-seven (67%) procedures were performed under sedation and 23 (33%) under local anesthesia. Forty-three (69%) women reported feeling cured or improved at 12 months follow-up and among them, 25 (40%) reported feeling cured. A total of 16 (23%) patients were subsequently treated, in detail 11 (16%) patients underwent MUS positioning, and 5 (7%) had an additional injection of Bulkamid. ICIQ and Contilife QoL showed a significant improvement at 1, 3, 6, and 12 months (all p < 0.001). CONCLUSIONS: Bulkamid injections are an effective and safe treatment option for women with SUI or stress-predominant MUI, providing good outcomes at 12 months.
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Resinas Acrílicas , Inyecciones , Incontinencia Urinaria de Esfuerzo , Humanos , Femenino , Persona de Mediana Edad , Incontinencia Urinaria de Esfuerzo/terapia , Estudios Retrospectivos , Anciano , Resultado del Tratamiento , Factores de Tiempo , Satisfacción del Paciente , Calidad de Vida , Estudios de Seguimiento , HidrogelesRESUMEN
Polyacrylamide (PAM) is a high-molecular-weight polymer with extensive applications. However, the inefficient natural degradation of PAM results in environmental accumulation of the polymer. Biodegradation is an environmentally friendly approach in the field of PAM treatment. The first phase of PAM biodegradation is the deamination of PAM, forming the product poly(acrylic acid) (PAA). The second phase of PAM biodegradation involves the cleavage of PAA into small molecules, which is a crucial step in the degradation pathway of PAM. However, the enzyme that catalyzes the degradation of PAA and the molecular mechanism remain unclear. Here, a novel monooxygenase PCX02514 is identified as the key enzyme for PAA degradation. Through biochemical experiments, the monooxygenase PCX02514 oxidizes PAA with the participation of NADPH, causing the cleavage of carbon chains and a decrease in the molecular weight of PAA. In addition, the crystal structure of the monooxygenase PCX02514 is solved at a resolution of 1.97 Å. The active pocket is in a long cavity that extends from the C-terminus of the TIM barrel to the protein surface and exhibits positive electrostatic potential, thereby causing the migration of oxygen-negative ions into the active pocket and facilitating the reaction between the substrates and monooxygenase PCX02514. Moreover, Arg10-Arg125-Ser186-Arg187-His253 are proposed as potential active sites in monooxygenase PCX02514. Our research characterizes the molecular mechanism of this monooxygenase, providing a theoretical basis and valuable tools for PAM bioremediation.
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Resinas Acrílicas , Biodegradación Ambiental , Oxigenasas de Función Mixta , Resinas Acrílicas/química , Oxigenasas de Función Mixta/metabolismo , Oxigenasas de Función Mixta/química , Dominio Catalítico , Modelos Moleculares , Cristalografía por Rayos X , Conformación ProteicaRESUMEN
Bone adhesives, as alternatives to traditional bone fracture treatment methods, have great benefits in achieving effective fixation and healing of fractured bones. However, current available bone adhesives have limitations in terms of weak mechanical properties, low adhesion strength, and inappropriate degradability, hindering their clinical applications. The development of bone adhesives with strong mechanical properties, adhesion strength, and appropriate degradability remains a great challenge. In this study, polyacrylic acid was incorporated with tetracalcium phosphate and O-phospho-L-serine to form a new bone adhesive via coordination and ionic interactions to achieve exceptional mechanical properties, adhesion strength, and degradability. The bone adhesive could achieve an initial adhesion strength of approximately 3.26 MPa and 0.86 MPa on titanium alloys and bones after 15 min of curing, respectively, and it increased to 5.59 MPa and 2.73 MPa, after 24 h of incubation in water or simulated body fluid (SBF). The compressive strength of the adhesive increased from 10.06 MPa to 72.64 MPa over two weeks, which provided sufficient support for the fractured bone. Importantly, the adhesive started to degrade after 6 to 8 weeks of incubation in SBF, which is beneficial to cell ingrowth and the bone healing process. In addition, the bone adhesives exhibited favorable mineralization capability, biocompatibility, and osteogenic activity. In vivo experiments showed that it has a better bone-healing effect compared with the traditional polymethyl methacrylate bone cement. These results demonstrate that the bone adhesive has great potential in the treatment of bone fractures.
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Resinas Acrílicas , Cementos para Huesos , Resinas Acrílicas/química , Cementos para Huesos/química , Cementos para Huesos/farmacología , Animales , Ensayo de Materiales , Ratones , Propiedades de Superficie , Titanio/químicaRESUMEN
BACKGROUND: Digitally fabricated dentures may require relining due to continual alveolar ridge resorption. However, studies evaluating the tensile bond strength (TBS) of digitally fabricated dentures bonded to denture liners are lacking. This study aimed to evaluate the TBS of autopolymerized, heat-polymerized, milled, and 3D printed denture base materials bonded to 2 acrylic-based and 2 silicone-based denture liners, both before and after thermocycling. Additionally, the impact of thermocycling on the TBS were also evaluated. METHODS: The TBS of 4 different denture base materials (Palapress (PL), Vertex Rapid Simplified (VR), Smile CAM total prosthesis (SC), and NextDent denture 3D+ (ND)) bonded to 2 acrylic-based (GC Soft-Liner (GC) and Tokuyama Rebase II (RB)) and 2 silicone-based (Ufi Gel P (UP) and Sofreliner Tough M (ST)) denture liners were tested. Specimens (n = 8) were divided into non-thermocycling and thermocycling groups. Non-thermocycling specimens were tested after 24-hours water immersion, while thermocycling specimens were underwent 5000 cycle and were immediately tested. Mode of failure was examined under a stereomicroscope. Data were analyzed using 2-way ANOVA and Tukey HSD tests (α = 0.05), and independent samples t test (α = 0.05) for TBS between non-thermocycling and thermocycling groups. RESULTS: For the non-thermocycling groups, within the same denture liner material, no significant differences were found between denture base materials, except the ND + RB group, which had significantly lower TBS. For the thermocycling groups, within the same denture liner material, the TBS in the PL group exhibited the highest and the ND group exhibited the lowest. Within the same denture base material, in both non-thermocycling and thermocycling groups, the TBS in the ST group exhibited the highest; in contrast, that in the GC group exhibited the lowest. No significant differences were observed in TBS between non-thermocycling and thermocycling groups, except for denture base materials bonded to the ST group, SC + UP, and ND + UP groups. CONCLUSIONS: Milled denture base can be relined with acrylic-based or silicone-based denture liner. However, cautions should be exercised when relining 3D printed denture base. Thermocycling did not affect TBS between acrylic-based denture liners and denture bases. In contrast, it affected the bond between silicone-based denture liner and denture base.
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Bases para Dentadura , Alineadores Dentales , Ensayo de Materiales , Impresión Tridimensional , Resistencia a la Tracción , Resinas Acrílicas/química , Recubrimiento Dental Adhesivo/métodos , Humanos , Polimerizacion , Materiales Dentales/química , Técnicas In Vitro , Calor , Análisis del Estrés Dental , Polimetil Metacrilato/química , Siliconas/química , Elastómeros de Silicona/químicaRESUMEN
The levels of uric acid (UA) and tyrosine (Tyr) in sweat reflect a person's overall health. However, simultaneously identifying several components in sweat remains challenging. Here, we achieve simultaneous detection of UA and Tyr by synthesizing CoWO4@CNT in a single step using a hydrothermal method. CoWO4's high catalytic efficacy and large CNT reaction area allow the detection of 1-1000 µM UA (LOD = 0.14 µM) and 5-1000 µM Tyr (LOD = 4.2 µM). To increase sweat collection, we developed a polydopamine-polyacrylamide (PDA-PAM) hydrogel with a sweat absorption rate of up to 226%. Finally, by monitoring sweat at various times of day, our sensors can discriminate between UA and Tyr in real sweat, and the results are consistent with the individuals' activity levels. Overall, the effective electrocatalytically active materials and PDA-PAM hydrogel improve the detection of UA and Tyr. The remarkable performance of CoWO4@CNT in real samples shows that it has the potential to improve health detection and real-time sweat analysis.
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Técnicas Biosensibles , Técnicas Electroquímicas , Hidrogeles , Sudor , Tirosina , Ácido Úrico , Ácido Úrico/análisis , Ácido Úrico/química , Sudor/química , Técnicas Biosensibles/métodos , Tirosina/química , Tirosina/análisis , Humanos , Hidrogeles/química , Técnicas Electroquímicas/métodos , Polímeros/química , Límite de Detección , Indoles/química , Resinas Acrílicas/químicaRESUMEN
Cerium oxide nanoparticles are known for their antibacterial effects resulting from Ce3+ to Ce4+ conversion. Application of such cerium oxide nanoparticles in dentistry has been previously considered but limited due to deterioration of mechanical properties. Hence, this study aimed to examine mesoporous silica (MCM-41) coated with cerium oxide nanoparticles and evaluate the antibacterial effects and mechanical properties when applied to dental composite resin. Cerium oxide nanoparticles were coated on the MCM-41 surface using the sol-gel method by adding cerium oxide nanoparticle precursor to the MCM-41 dispersion. The samples were tested for antibacterial activity against Streptococcus mutans via CFU and MTT assays. The mechanical properties were assessed by flexural strength and depth of cure according to ISO 4049. Data were analyzed using a t-test, one-way ANOVA, and Tukey's post-hoc test (p = 0.05). The experimental group showed significantly increased antibacterial properties compared to the control groups (p < 0.005). The flexural strength exhibited a decreasing trend as the amount of cerium oxide nanoparticle-coated MCM-41 increased. However, the flexural strength and depth of cure values of the silane group met the ISO 4049 standard. Antibacterial properties increased with increasing amounts of cerium oxide nanoparticles. Although the mechanical properties decreased, silane treatment overcame this drawback. Hence, the cerium oxide nanoparticles coated on MCM-41 may be used for dental resin composite.
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Antibacterianos , Cerio , Resinas Compuestas , Nanopartículas , Dióxido de Silicio , Streptococcus mutans , Cerio/química , Cerio/farmacología , Dióxido de Silicio/química , Antibacterianos/farmacología , Antibacterianos/química , Resinas Compuestas/química , Resinas Compuestas/farmacología , Streptococcus mutans/efectos de los fármacos , Nanopartículas/química , Resinas Acrílicas/química , Ensayo de Materiales , Poliuretanos/química , Poliuretanos/farmacología , Resistencia Flexional , PorosidadRESUMEN
Hierarchical compartmentalization responding to changes in intracellular and extracellular environments is ubiquitous in living eukaryotic cells but remains a formidable task in synthetic systems. Here we report a two-level compartmentalization approach based on a thermo-responsive aqueous two-phase system (TR-ATPS) comprising poly(N-isopropylacrylamide) (PNIPAM) and dextran (DEX). Liquid membraneless compartments enriched in PNIPAM are phase-separated from the continuous DEX solution via liquid-liquid phase separation at 25 °C and shrink dramatically with small second-level compartments generated at the interface, resembling the structure of colloidosome, by increasing the temperature to 35 °C. The TR-ATPS can store biomolecules, program the spatial distribution of enzymes, and accelerate the overall biochemical reaction efficiency by nearly 7-fold. The TR-ATPS inspires on-demand, stimulus-triggered spatiotemporal enrichment of biomolecules via two-level compartmentalization, creating opportunities in synthetic biology and biochemical engineering.
Asunto(s)
Resinas Acrílicas , Dextranos , Temperatura , Resinas Acrílicas/química , Dextranos/química , Agua/química , Biología Sintética/métodosRESUMEN
In this study, we propose a self-limiting growth model forBacillus subtilisspores confined within porous polyacrylamide (PA) hydrogels. We observed thatB. subtilisspores germinate into vegetative cells within the hydrogel matrix, forming spherical colonies. These colonies expand until the mechanical stress they exert on their environment surpasses the yield stress of the hydrogel, leading to formation of a nonpermeable layer that halts nutrient diffusion and forces the bacteria to resporulate. These novel observations suggest a model to explain why bacterial growth in confined environments and material interfaces may be limited, providing insight for natural phenomena and biotechnological applications involving bacterial encapsulation.
Asunto(s)
Resinas Acrílicas , Hidrogeles , Estrés Mecánico , Resinas Acrílicas/química , Hidrogeles/química , Bacillus subtilis/crecimiento & desarrollo , Porosidad , Modelos BiológicosRESUMEN
Electronic skin (e-skin) is considered as a highly promising interface for human-computer interaction systems and wearable electronic devices. Through elaborate design and assembly of various materials, it possesses multiple characteristics similar to human skin, including remarkable flexibility, stretchability, sensitivity to temperature and humidity, biocompatibility, and efficient interfacial ion/electron transport capabilities. Here, we innovatively integrate multifunctional carbon quantum dots (CQDs), which exhibit conductivity, antibacterial properties, ultraviolet absorption, and fluorescence emission, with poly(acrylic acid) and glycerin (Gly) into a three-dimensional network structure of natural goatskin collagen fibers. Through a top-down design strategy enhanced by hydrogen bond reconstruction, we successfully fabricated a novel transparent e-skin (PAC-eSkin). This e-skin exhibited significant tensile properties (4.94 MPa of tensile strength and 263.42% of a maximum breaking elongation), while also possessing Young's modulus similar to human skin (2.32 MPa). It is noteworthy that the functionalized CQDs used was derived from discarded goat hair, and the addition of Gly gave PAC-eSkin excellent antifreezing and moisturizing properties. Due to the presence of ultrasmall CQDs, which creates efficient ion/electron transport channels within PAC-eSkin, it could rapidly sense human motion and physiological signals (with a gauge factor (GF) of 1.88). Furthermore, PAC-eSkin had the potential to replace traditional electrode patches for real-time monitoring of electrocardiogram, electromyogram, and electrooculogram signals, with a higher SNR (signal-to-noise ratio) of 25.1 dB. Additionally, the customizable size and shape of PAC-eSkin offer vast possibilities for the construction of single-electrode triboelectric nanogenerator systems. We have reason to believe that the design and development of this transparent e-skin based on CQDs-functionalized dermal collagen matrices can pave a new way for innovations in human-computer interaction interfaces and their sensing application in diverse scenarios.