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1.
Gerontology ; 70(6): 572-584, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38461811

RESUMEN

INTRODUCTION: Although the relationship between the number of teeth and frailty has been extensively studied, the mediating role of nutrition status in the association between the number of teeth and frailty remains to be clarified. METHODS: A number of 6,664 participants lived in the communities of West China were analyzed in our study. Physical frailty was determined based on the phenotype established by Fried. Nutrition status was evaluated using the Mini Nutrition Assessment-Short Form (MNA-SF) scale. Multiple linear regression was employed to evaluate the direct relationships between the number of teeth, nutrition, and frailty. Mediation models and structural equation model (SEM) pathway analysis were used to test the mediating role of nutrition status in the relationship between the number of teeth and frailty. RESULTS: Among the 6,664 participants aged over 50 years old, the prevalence of frailty was 6.2%. Multiple linear regression analysis showed a significant total relationship between the number of teeth (ß = -0.359, 95% CI: -0.473 to -0.244, p < 0.001) and frailty. After adjusting for MNA-SF scores, the relationship between the number of teeth and frailty remained significant (ß = -0.327, 95% CI: -0.443 to -0.211, p < 0.001), indicating a partial mediating effect of nutrition. Mediation analysis verified that nutrition partially mediated the relationship between the number of teeth and frailty (indirect effect estimate = -0.0121, bootstrap 95% CI: -0.0151 to -0.0092; direct effect estimate = -0.0874, bootstrap 95% CI: -0.1086 to -0.0678) in the fully adjusted model. This mediating effect occurred through influencing weight loss, low level of physical activity, and debility. SEM framework pathway analysis confirmed the association between the number of teeth, nutrition, and frailty. CONCLUSIONS: Our findings demonstrated that frailty was correlated with the number of teeth and poorer nutritional status, with nutrition partially mediating the correlation between the number of teeth and frailty. Our results supported early nutritional evaluation and intervention in oral health to decrease the risk of frailty.


Asunto(s)
Anciano Frágil , Fragilidad , Estado Nutricional , Humanos , Masculino , Femenino , Estudios Transversales , Anciano , Persona de Mediana Edad , Fragilidad/epidemiología , China/epidemiología , Anciano Frágil/estadística & datos numéricos , Evaluación Geriátrica/métodos , Evaluación Nutricional , Pérdida de Diente/epidemiología , Anciano de 80 o más Años , Modelos Lineales , Prevalencia
2.
Chem Soc Rev ; 51(12): 5136-5174, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35666131

RESUMEN

Recent years have witnessed increasingly rapid advances in nanocarrier-based biomedicine aimed at improving treatment paradigms for cancer. Nanogels serve as multipurpose and constructed vectors formed via intramolecular cross-linking to generate drug delivery systems, which is attributed predominantly to their satisfactory biocompatibility, bio-responsiveness, high stability, and low toxicity. Recently, immunotherapy has experienced unprecedented growth and has become the preferred strategy for cancer treatment, and mainly involves the mobilisation of the immune system and an enhanced anti-tumour immunity of the tumour microenvironment. Despite the inspiring success, immunotherapeutic strategies are limited due to the low response rates and immune-related adverse events. Like other nanomedicines, nanogels are comparably limited by lower focal enrichment rates upon introduction into the organism via injection. Because nanogels are three-dimensional cross-linked aqueous materials that exhibit similar properties to natural tissues and are structurally stable, they can comfortably cope with shear forces and serum proteins in the bloodstream, and the longer circulation life increases the chance of nanogel accumulation in the tumour, conferring deep tumour penetration. The large specific surface area can reduce or eliminate off-target effects by introducing stimuli-responsive functional groups, allowing multiple physical and chemical modifications for specific purposes to improve targeting to specific immune cell subpopulations or immune organs, increasing the bioavailability of the drug, and conferring a low immune-related adverse events on nanogel therapies. The slow release upon reaching the tumour site facilitates long-term awakening of the host's immune system, ultimately achieving enhanced therapeutic effects. As an effective candidate for cancer immunotherapy, nanogel-based immunotherapy has been widely used. In this review, we mainly summarize the recent advances of nanogel-based immunotherapy to deliver immunomodulatory small molecule drugs, antibodies, genes and cytokines, to target antigen presenting cells, form cancer vaccines, and enable chimeric antigen receptor (CAR)-T cell therapy. Future challenges as well as expected and feasible prospects for clinical treatment are also highlighted.


Asunto(s)
Vacunas contra el Cáncer , Neoplasias , Sistemas de Liberación de Medicamentos , Humanos , Inmunoterapia/métodos , Nanogeles , Neoplasias/tratamiento farmacológico , Microambiente Tumoral
3.
BMC Geriatr ; 22(1): 649, 2022 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-35941556

RESUMEN

OBJECTIVES: The relationship between the number of teeth and sarcopenia remains poorly investigated. Although nutrition plays an important role in maintaining bone and muscle health, the complex relationship between number of teeth and nutrition in the pathogenesis of sarcopenia remains to be elucidated. METHODS: A large multi-ethnic sample of 4149 participants aged over 50 years old from West China Health and Aging Trend (WCHAT) study was analyzed. We examined the associations between number of teeth with nutritional status and sarcopenia, and the mediating role of nutrition in the association between number of teeth and sarcopenia. Sarcopenia was defined according to the Asian Working Group for Sarcopenia 2019. We assessed nutrition using Mini Nutrition Assessment-Short Form (MNA-SF) scale. Direct relationships between number of teeth, nutrition and sarcopenia were assessed using multiple linear regression. Mediation models and structural equation model (SEM) pathway analysis were used to test the mediating role of nutrition in the relationship between number of teeth and sarcopenia. RESULTS: Of 4149 participants aged 50 years old or older, the prevalence of sarcopenia was 22.5, 9.0% for moderate sarcopenia, and 13.5% for severe sarcopenia, respectively. Regression analysis indicated a total association between number of teeth (ß = - 0.327, 95% CI - 0.471 to - 0.237, p < 0.001) and sarcopenia. After adjusted MNA-SF scores, the association between number of teeth and sarcopenia was still significant (ß = - 0.269, 95% CI - 0.364 to - 0.175, p < 0.001), indicating a partial mediation effect of nutrition. Mediation analysis verified nutrition partially mediate the associations between number of teeth and sarcopenia (indirect effect estimate = - 0.0272, bootstrap 95% CI - 0.0324 to - 0.0222; direct effect estimate = - 0.0899, bootstrap 95% CI - 0.1049 to - 0.0738). And this mediation effect was through impacting SMI (indirect effect estimate = - 0.0283, bootstrap 95% CI - 0.0336 to - 0.0232) and grip strength (indirect effect estimate = - 0.0067, bootstrap 95% CI - 0.0094 to - 0.0043). Structural equation model (SEM) framework pathway analysis confirmed the association between number of teeth, nutrition, and sarcopenia. CONCLUSIONS: Our findings indicated that sarcopenia was associated with number of teeth and poorer nutritional status, with nutrition partially mediating the association between number of teeth and sarcopenia. Our findings supported early nutritional assessment and intervention in oral health to mitigate the risk of sarcopenia.


Asunto(s)
Sarcopenia , Anciano , Estudios Transversales , Evaluación Geriátrica , Fuerza de la Mano , Humanos , Persona de Mediana Edad , Evaluación Nutricional , Estado Nutricional , Sarcopenia/diagnóstico , Sarcopenia/epidemiología
4.
Int J Mol Sci ; 23(18)2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36142665

RESUMEN

A novel high-throughput array analytical platform based on derived ß-cyclodextrin supramolecular imprinted polymer (SMIP) fibers was constructed to achieve selective enrichment and removal of parabens. SMIP fiber arrays have abundant imprinting sites and introduce the host−guest inclusion effect of the derived ß-cyclodextrin, which is beneficial to significantly improve the adsorption ability of fiber for parabens. Upon combination with HPLC, a specific and sensitive recognition method was developed with a low limit of detection (0.003−0.02 µg/L, S/N = 3) for parabens analysis in environmental water. This method has a good linearity (R > 0.9994) in the linear range of 0.01−200 µg/L. The proposed SMIP fiber array with high-throughput adsorption capacity has great potential in monitoring water pollution, which also provides a reliable reference for the analysis of more categories of pharmaceutical and personal care product pollutants.


Asunto(s)
Cosméticos , Contaminantes Ambientales , Impresión Molecular , beta-Ciclodextrinas , Adsorción , Cromatografía Líquida de Alta Presión , Contaminantes Ambientales/análisis , Impresión Molecular/métodos , Parabenos , Preparaciones Farmacéuticas , Polímeros , Agua
5.
Biomed Microdevices ; 21(3): 58, 2019 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-31227909

RESUMEN

Traditional immunomagnetic assays for the isolation and recovery of circulating tumor cells (CTCs) usually require sophisticated device or intense magnetic field to simultaneously achieve high capture efficiency and high throughout. In this study, a simple microfluidic chip featured with nanoroughened channel substrate was developed for effectively capture and release of CTCs based on an immunomagnetic chip-based approach. The nanoroughened substrate aims to increase the cell-surface contact area, facilitate the immobilization of magnet particles (MPs) and accommodate cell attachment tendency. Hep3B tumor cells were firstly conjugated with MPs that were functionalized with anti-EpCAM. Comparing with the flat channel, MPs modified tumor cells can be more effectively captured on nanoroughened substrate at the presence of the magnetic field. Upon the removal of magnetic field, these captured cells can be released from the device and collected for further analysis. Under the optimum operating conditions, the capture efficiency of tumor cells was obtained as high as ~90% with a detection limit of 10 cell per mL. Additionally, recovery rates of trapped tumor cells at various densities all exceeded 90% and their biological potencies were well retained by investigating the cell attachment and proliferation. Therefore, the present approach may potentially be used in clinical CTC analysis for cancer diagnosis and prognosis as well as the fundamental understanding of tumor metastasis.


Asunto(s)
Dimetilpolisiloxanos/química , Separación Inmunomagnética/instrumentación , Nanoestructuras/química , Células Neoplásicas Circulantes/patología , Adhesión Celular , Línea Celular Tumoral , Proliferación Celular , Molécula de Adhesión Celular Epitelial/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Células Neoplásicas Circulantes/metabolismo , Propiedades de Superficie , Factores de Tiempo
6.
Mol Pharm ; 16(1): 49-59, 2019 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-30485109

RESUMEN

Reactive oxygen species (ROS) are highly overproduced in cancerous tissues, and thus oxidation-responsive nanoparticles (NPs) have emerged as a promising drug carrier for cancer-targeted drug delivery. In this study, we successfully synthesized poly(vanillyl alcohol- co-oxalate) (PVAX) polymer with an excellent ROS-responsive capacity. A well-established emulsion-solvent evaporation method was used to fabricate PVAX-based curcumin (CUR)-loaded NPs (PVAX-NPs) and their counterparts (poly(lactic- co-glycolic acid)-based CUR-loaded NPs, PLGA-NPs). It was found that these NPs had a hydrodynamic particle size of approximately 245 nm, narrow size distribution (polydispersity index less than 0.1), negative zeta potential (around -18 mV), smooth surface appearance, and high drug encapsulation efficiency. Moreover, we found that the CUR release rate of PVAX-NPs was greatly increased in the presence of a hydrogen peroxide-rich environment due to the cleavage of polyoxalate ester bonds in PVAX polymer, resulting in the evenly distribution of CUR within the whole cancer cells. More importantly, PVAX-NPs exhibited much stronger anticancer activities and pro-apoptotic capacities than PLGA-NPs both in vitro and in vivo. These results clearly demonstrate that these ROS-responsive PVAX-NPs can be exploited as a robust anticancer drug delivery platform in chemotherapy.


Asunto(s)
Antineoplásicos/química , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/química , Polímeros/química , Curcumina/química , Portadores de Fármacos/química , Humanos , Células MCF-7 , Tamaño de la Partícula , Especies Reactivas de Oxígeno/metabolismo
7.
Biomacromolecules ; 20(3): 1334-1345, 2019 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-30703318

RESUMEN

Polymeric microneedles have attracted increasing attention as a minimally invasive platform for delivering drugs or vaccines in a more patient-friendly manner. However, traditional microfabrication techniques using negative molds with needle-shaped cavities usually require cumbersome centrifugation and vacuum degassing processes, which have restricted the scaled-up mass production of polymeric microneedles. Herein, a novel polydimethylsiloxane (PDMS)-based negative mold with cavities packed with silk fibroin scaffold is developed for rapid fabrication of polymeric microneedles, which comprise primarily the composition of poly(ethylene glycol) diacrylate (PEGDA) and sucrose as the needle matrix. Fibroin scaffolds can instantly adsorb prepolymer solution due to capillary force, and subsequently initiate the formation of microneedles via photoinduced polymerization. Based on three types of model drugs, including Rhodamine B (RhB), indocyanine green (ICG), and doxorubicin (DOX), the fabricated PEGDA/sucrose microneedles can realize effective transdermal delivery and controllable release of therapeutic molecules by regulating the sucrose content. The presented method provides a simple strategy for quick fabrication of polymeric microneedles toward transdermal drug delivery applications.


Asunto(s)
Administración Cutánea , Sistemas de Liberación de Medicamentos , Fibroínas/química , Agujas , Polietilenglicoles/química , Sacarosa/química , Animales , Doxorrubicina/administración & dosificación , Células Endoteliales de la Vena Umbilical Humana , Humanos , Verde de Indocianina/administración & dosificación , Ratones , Porosidad , Rodaminas/administración & dosificación
8.
Biomacromolecules ; 20(3): 1190-1202, 2019 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-30658038

RESUMEN

Polymeric prodrug based on therapeutic nanomedicine has demonstrated great promise for effective tumor growth inhibition, however, the drawbacks of low drug-loading and weak micellar stability limit its application for clinical cancer therapy. Herein, a reduction-responsive starburst block copolymer prodrug CCP [ß-cyclodextrin (ß-CD)-PCPTXX-POEGMA, XX: SS or CC] has been developed for cancer therapy. And CCP is composed of ß-CD-Br core with multiple reactive sites, as well as a diblock copolymer containing hydrophobic polymerized camptothecin (PCPT) prodrug chain and hydrophilic poly[(ethylene glycol) methyl ether methacrylate] (OEGMA) chain. A family of CCP polymeric prodrugs with different drug loading contents (up to 25%) and various sizes of unimolecular micelles (UMs) (around 30 nm) were obtained by adjusting the block ratio of PCPTXX and POEGMA. On account of the amphiphilic structure feature, CPP could take shape water-soluble UMs in aqueous medium with excellent micellar stability. Under imitatively reductive tumor microenvironment, anticancer drug CPT could rapidly escape from CCP UMs in terms of disulfide bond breakage. However, this behavior is strongly refrained in the physiological environment. In vitro and in vivo outcome confirmed that CCP UMs showed excellent performance of sufficient tumor accumulation, high-efficiency tumor growth inhibition and low-toxicity for healthy tissues. Based on these gratifying therapeutic efficacy, it is believed that as-present starburst prodrug strategy can offer a brand-new insight for high-efficiency therapeutic nanoplatforms for chemotherapy application.


Asunto(s)
Antineoplásicos/administración & dosificación , Sistemas de Liberación de Medicamentos , Micelas , Polímeros/química , Profármacos/química , Animales , Antineoplásicos/química , Camptotecina/administración & dosificación , Camptotecina/química , Femenino , Células HeLa , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Células MCF-7 , Ratones Endogámicos BALB C , Ratones Desnudos , Microambiente Tumoral , beta-Ciclodextrinas/química
9.
Nanomedicine ; 17: 1-12, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30654184

RESUMEN

Taking advantage of the mesoporous structure of bismuth sulfide nanostars (Bi2S3 NSs), a chemotherapeutic drug of doxorubicin (DOX) and a photosensitizer of chlorin e6 (Ce6) were concurrently loaded in the PEGylated Bi2S3 NSs to formulate a multifunctional nanocomplex (BPDC NSs) for tumor theranostics. BPDC NSs have excellent photothermal conversion efficiency and a capacity of yielding reactive oxygen species (ROS) upon laser irradiation, and can realize on-demand drug release by either pH-activation or thermal induction. Accumulation of the nanodrug could be monitored in real-time by infrared thermal imaging, fluorescence imaging and computed tomography (CT). More importantly, the combination effects of photothermal therapy (PTT), photodynamic therapy (PDT) and chemotherapy were demonstrated to dramatically suppress solid tumors without recurrence in vivo. Featuring low systemic toxicity and high biocompatibility, this nanoplatform could be a promising derivative of Bi2S3 NSs for imaging-guided theranostics of cancer.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Doxorrubicina/administración & dosificación , Neoplasias/diagnóstico por imagen , Neoplasias/terapia , Fármacos Fotosensibilizantes/administración & dosificación , Porfirinas/administración & dosificación , Animales , Antibióticos Antineoplásicos/uso terapéutico , Bismuto/uso terapéutico , Línea Celular Tumoral , Clorofilidas , Preparaciones de Acción Retardada/uso terapéutico , Doxorrubicina/uso terapéutico , Hipertermia Inducida , Ratones , Nanopartículas/uso terapéutico , Nanopartículas/ultraestructura , Imagen Óptica , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Polietilenglicoles/uso terapéutico , Porosidad , Porfirinas/uso terapéutico , Sulfuros/uso terapéutico , Nanomedicina Teranóstica , Tomografía Computarizada por Rayos X
10.
Mol Pharm ; 14(11): 4032-4041, 2017 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-28980818

RESUMEN

Stimuli-responsive nanomedicine with theranostic functionalities with reduced side-effects has attracted growing attention, although there are some major obstacles to overcome before clinical applications. Herein, we present an acid-activatable theranostic unimolecular micelles based on amphiphilic star-like polymeric prodrug to systematically address typical existing issues. This smart polymeric prodrug has a preferable size of about 35 nm and strong micellar stability in aqueous solution, which is beneficial to long-term blood circulation and efficient extravasation from tumoral vessels. Remarkably, the polymeric prodrug has a high drug loading rate up to 53.1 wt%, which induces considerably higher cytotoxicity against tumor cells (HeLa cells and MCF-7 cells) than normal cells (HUVEC cells) suggesting a spontaneous tumor-specific targeting capability. Moreover, the polymeric prodrug can serve as a fluorescent nanoprobe activated by the acidic microenvironment in tumor cells, which can be used as a promising platform for tumor diagnosis. The superior antitumor effect in this in vitro study demonstrates the potential of this prodrug as a promising platform for drug delivery and cancer therapy.


Asunto(s)
Antineoplásicos/química , Polímeros/química , Profármacos/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Células HeLa , Células Endoteliales de la Vena Umbilical Humana , Humanos , Células MCF-7 , Micelas
11.
Biomacromolecules ; 17(5): 1673-83, 2016 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-27010718

RESUMEN

This article describes molecular design, synthesis and characterization of colloidal nanoparticles containing polycaprolactone-grafted conjugated polymers that exhibit strong far red/near-infrared (FR/NIR) fluorescence for bioimaging. Specifically, we synthesized two kinds of conjugated polymer bottle brushes (PFTB(out)-g-PCL and PFTB(in)-g-PCL) with different positions of the hexyl groups on the thiophene rings. A synthetic amphiphilic block copolymer PCL-b-POEGMA was employed as surfactants to encapsulate PFTB-g-PCL polymers into colloidal nanoparticles (denoted as "nanoREDs") in aqueous media. The chain length of the PCL side chains in PFTB-g-PCL played a critical role in determining the fluorescence properties in both bulk solid states and the colloidal nanoparticles. Compared to semiconducting polymer dots (Pdots) composed of PFTB(out) without grafted PCL, nanoRED(out) showed at least four times higher fluorescence quantum yield (∼20%) and a broader emission band centered at 635 nm. We further demonstrated the application of this new class of nanoREDs for effective labeling of L929 cells and HeLa cancer cells with good biocompatibility. This strategy of hydrophobic-sheath segregated macromolecular fluorophores is expected to be applicable to a broad range of conjugated polymers with tunable optical properties for applications such as bioimaging.


Asunto(s)
Fibroblastos/citología , Colorantes Fluorescentes/química , Imagen Molecular/métodos , Nanopartículas/química , Poliésteres/química , Polímeros/química , Células Cultivadas , Fibroblastos/metabolismo , Fluorescencia , Células HeLa , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Puntos Cuánticos , Espectrofotometría Infrarroja
12.
Materials (Basel) ; 17(7)2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38612175

RESUMEN

Dental amalgams have been used by dentists for the restoration of posterior human teeth. However, there have been concerns about the release of mercury from amalgams into the oral cavity. The objective of the present research is to study the effect of titanium (Ti) nanoparticles on the microstructural mechanism of the release of mercury vapor in two commonly used brands of dental amalgam (the Dispersalloy: 11.8% Cu; the Sybralloy: 33% Cu). Ti powder was added to both the Dispersalloy and the Sybralloy in increments of 10 mg up to 80 mg. The addition of Ti powder to both brands of dental amalgam has been found to result in a considerable decrease in Hg vapor release. The decrease in the Hg vapor release due to Ti addition has been explained by the formation of strong Hg-Ti covalent bonds, which reduce the availability of Hg atoms for evaporation. The Ti atoms in excess of the solubility limit of Ti in Hg reside in the grain boundaries, which also reduces the evaporation of Hg from the amalgam. The binding of Hg with Ti via a strong covalent bond also results in a significant improvement in mechanical properties such as Vickers hardness.

13.
J Mater Chem B ; 11(5): 1020-1028, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36637004

RESUMEN

Molecularly imprinted solid-phase microextraction fibers with multi-site recognition were prepared for the simultaneous enrichment of three cross-class environmental endocrine disruptors (EEDs) in environmental water. The surface morphology of the multi-site recognition molecularly imprinted fibers was characterized using scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, and surface area and pore size analyzer. Under optimal extraction conditions, the molecularly imprinted fibers showed higher extraction capacity to bisphenol F, diethyl phthalate, and methyl paraben than non-imprinted polymer fibers and commercial fibers. Compared with commercial solid-phase microextraction fibers, the multi-site recognition molecularly imprinted fibers showed superior extraction performance at different concentrations of analytes. The selectivity study confirmed that the multi-site recognition molecularly imprinted solid-phase microextraction fibers were highly selective not only for specific template molecules but also for bisphenols, parabens, and phthalates. Furthermore, the method achieved a limit of detection of 0.003-0.02 µg L-1 for the three cross-class EEDs in environmental water samples with recoveries ranging from 75.76% to 112.69% and relative standard deviations below 11.46%. Thus, the novel MIP fibers with multi-site recognition prepared in this work have provided a promising approach in the field of specific adsorption and a strategy for the simultaneous and sensitive monitoring of multiple cross-class trace EEDs.


Asunto(s)
Disruptores Endocrinos , Impresión Molecular , Impresión Molecular/métodos , Agua , Microextracción en Fase Sólida/métodos , Polímeros/química
14.
Materials (Basel) ; 16(9)2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37176331

RESUMEN

Dental amalgam is an alloy consisting of a mixture of fine metallic powder of silver, tin, zinc, copper, and a trace amount of palladium in combination with about fifty percent elemental mercury that forms a matrix phase. Dental amalgams consisting of a high-copper content are the most common types of alloys currently utilized for the restoration of decayed, broken, and fractured posterior human teeth. The present research objective was primarily to improve the material properties by determining and analyzing the amount of mercury vapor released from dental amalgam received from eight different commercial brands. The mechanical hardness of the alloys was found to increase with an increase in copper content in the amalgam. The effect of copper addition on material aging was also studied. During the release of mercury vapor, the corresponding energies associated with the release of mercury vapor from each sample were determined for each successive measurement. The results indicated that increasing the copper content of the amalgam counters the release of mercury vapor from posterior teeth and improves the hardness properties.

15.
Int J Biol Macromol ; 253(Pt 4): 127104, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37769758

RESUMEN

Inspired by protein post-translational modification (PTM), post-imprinting modification (PIM) has been proposed and developed to prepare novel molecularly imprinted polymers (MIPs), which are similar to functionalized biosynthetic proteins. The PIM involves site-directed modifications in the imprinted cavity of the MIP, such as introducing high-affinity binding sites and introducing fluorescent signal molecules. This modification makes the MIP further functionalized and improves the shortcomings of general molecular imprinting, such as single function, low selectivity, low sensitivity, and inability to fully restore the complex function of natural antibodies. This paper describes the characteristics of PIM strategies, reviews the latest research progress in the recognition and detection of protein biomarkers such as lysozyme, prostate-specific antigen, alpha-fetoprotein, human serum albumin, and peptides, and further discusses the importance, main challenges, and development prospects of PIM. The PIM technology has the potential to develop a new generation of biomimetic recognition materials beyond natural antibodies. It can be used in bioanalysis and other multitudinous fields for its unique features in molecule recognition.


Asunto(s)
Materiales Biomiméticos , Impresión Molecular , Humanos , Masculino , Polímeros Impresos Molecularmente , Polímeros/química , Anticuerpos/química , Antígeno Prostático Específico
16.
J Mater Chem B ; 11(22): 4991-4999, 2023 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-37218576

RESUMEN

A kind of selective enrichment material based on a homemade molecularly imprinted polymer (MIP) fiber array with high adsorption capacity was developed for the accurate analysis of estrogens in food samples. Here, the MIP with 17ß-estradiol as the template was obtained by in situ polymerization. The chemical composition, morphologies, surface area, and pore size of the polymer were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and Brunauer-Emmett-Teller theory. The extraction time, desorption solvent, desorption time, ionic strength, and the pH of solution were investigated to ascertain the best extraction conditions. Under the optimal extraction conditions, three fiber coatings of 17ß-estradiol MIP and commercial polyacrylate (PA) were bound to a homemade handle to assemble the fiber array, respectively. The findings showed that the three-fiber array of the MIP significantly improved the extraction capacity by 145 times compared to PA. The MIP fiber array showed high adsorption capacity for the template molecule 17ß-estradiol and its structural analogues estrone, bisphenol F, bisphenol B, and bisphenol A, with enrichment factors of 99.60-133.16. A molecularly imprinted polymer solid-phase microextraction fiber array (MIP-SPME fiber array) coupled with high-performance liquid chromatography-diode array detection was used for the analysis and detection of the five estrogens in milk and yogurt samples. Satisfactory recoveries were achieved ranging from 74.75-119.41% with <9.42% relative standard deviations. The developed method for the simultaneous determination of trace estrogens in food samples exhibited a limit of detection of 0.33 µg L-1. The MIP-SPME fiber array provided an available strategy for improving the selectivity and adsorption capacity of SPME for trace target component analysis in complex matrices and increasing the sensitivity of the analytical method.


Asunto(s)
Estrógenos , Impresión Molecular , Estrógenos/análisis , Microextracción en Fase Sólida/métodos , Polímeros Impresos Molecularmente , Impresión Molecular/métodos , Estradiol/análisis
17.
J Control Release ; 358: 219-231, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37084891

RESUMEN

Pyroptosis is a highly inflammatory programmed cell death that activates inflammatory response, reverses immunosuppression and promotes systemic immune response for solid tumors treatment. However, the uncontrollable and imprecise process of pyroptosis stimulation leads to a scanty therapeutic effect. Here, we report a GSH/ROS dual response nanogel system (IMs) that can actively target the overexpressed mannose receptor (MR) of cancer cells, serve ultra-stable photothermal capacity of indocyanine green (ICG), induce cell pyroptosis and achieve enhanced tumor immune response. Photo-triggered IMs induce cytoplasmic Ca2+ introgression and activate caspase-3 through photo-activated ICG. The disconnect of SeSe bonds can break the oxidation and reduction balance of tumor cells, causing oxidative stress and synergistically enhancing caspase-3 cleavage, and regulating cell pyroptosis ultimately. Combined with anti-programmed death receptor 1 (anti-PD-1), the nanogel system not only effectivly suppress both primary tumor and distance tumor but also prolong the survival period of mice. This work introduces a strategy to optimize the photothermal performance of ICG and enhances tumor immune response mediated by triggering pyroptosis, which provides an impressive option for immune checkpoint blockade therapy.


Asunto(s)
Neoplasias , Piroptosis , Ratones , Animales , Caspasa 3 , Nanogeles , Inmunoterapia , Verde de Indocianina/química , Línea Celular Tumoral
18.
Chem Commun (Camb) ; 59(7): 932-935, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36597866

RESUMEN

Glutathione-responsive nanogels (CDNPs) crosslinked via crosslinker DBHD with the BRAF inhibitor dabrafenib and the COX2 inhibitor celecoxib were fabricated. The CDNPs can effectively induce tumor cell pyroptosis to activate robust antitumor immunity. Additionally, CDNPs combined with αPD-1 antibody greatly inhibited tumor growth in a melanoma mouse model with a prolonged survival time.


Asunto(s)
Inhibidores de la Ciclooxigenasa 2 , Melanoma , Ratones , Animales , Inhibidores de la Ciclooxigenasa 2/farmacología , Inhibidores de la Ciclooxigenasa 2/uso terapéutico , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/uso terapéutico , Nanogeles , Piroptosis , Melanoma/tratamiento farmacológico , Inhibidores de Proteínas Quinasas , Bioingeniería , Inmunoterapia , Oximas , Mutación
19.
Biosensors (Basel) ; 12(8)2022 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-36004972

RESUMEN

Molecular imprinting-aptamer techniques exhibit the advantages of molecular imprinting and aptamer technology. Hybrids of molecularly imprinted polymer-aptamer (MIP-aptamer) prepared by this technique have higher stability, binding affinity and superior selectivity than conventional molecularly imprinted polymers or aptamers. In recent years, molecular imprinting-aptamer technologies have attracted considerable interest for the selective recognition of target molecules in complex sample matrices and have been used in molecular recognition such as antibiotics, proteins, viruses and pesticides. This review introduced the development of molecular imprinting-aptamer-combining technologies and summarized the mechanism of MIP-aptamer formation. Meanwhile, we discussed the challenges in preparing MIP-aptamer. Finally, we summarized the application of MIP-aptamer to the molecular recognition in disease diagnosis, environmental analysis, food safety and other fields.


Asunto(s)
Aptámeros de Nucleótidos , Impresión Molecular , Aptámeros de Nucleótidos/química , Inocuidad de los Alimentos , Impresión Molecular/métodos , Polímeros/química
20.
Biosensors (Basel) ; 12(8)2022 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-36004991

RESUMEN

Paper-based analytical devices (PADs) are highly effective tools due to their low cost, portability, low reagent accumulation, and ease of use. Molecularly imprinted polymers (MIP) are also extensively used as biomimetic receptors and specific adsorption materials for capturing target analytes in various complex matrices due to their excellent recognition ability and structural stability. The integration of MIP and PADs (MIP-PADs) realizes the rapid, convenient, and low-cost application of molecular-imprinting analysis technology. This review introduces the characteristics of MIP-PAD technology and discusses its application in the fields of on-site environmental analysis, food-safety monitoring, point-of-care detection, biomarker detection, and exposure assessment. The problems and future development of MIP-PAD technology in practical application are also prospected.


Asunto(s)
Impresión Molecular , Polímeros , Adsorción , Polímeros/química
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