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1.
Macromol Rapid Commun ; 44(6): e2200826, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36414542

RESUMEN

Polymers of intrinsic microporosity (PIMs) are a class of microporous organic materials that contain interconnected pores of less than 2 nm in diameter. Such materials are of great potential used in membranes for molecular separation, such as drug fractionation in pharmaceutical industry. However, the PIMs membranes are often susceptible to low separation selectivity toward different molecules due to their wide pore size distribution. Herein, a linear polyimide, Matrimid, is incorporated with PIM-1 (a typical member of PIMs) by solution blending, and the blends are dip-coated onto a polyimide P84 support membrane to prepare thin-film composite (TFC) membranes to control pore size distribution while keep high microporosity. The component miscibility, pore characteristics, and molecular separation performances of the Matrimid/PIM-1 TFC membranes are investigated in detail. The Matrimid and PIM-1 are partially miscible due to their similar Hansen solubility parameters. The Matrimid endows the selective layers (coatings) with narrower pore size distribution due to more compact chain packing. The prepared Matrimid/PIM-1 TFC membranes show high selectivity for separation of riboflavin (80% of retention) and isatin (only 5% of retention). The developed membranes exhibit great potential for separating molecules with different molecular weights.


Asunto(s)
Fraccionamiento Químico , Membranas Artificiales , Polímeros , Solventes , Fraccionamiento Químico/métodos , Isatina/química , Isatina/aislamiento & purificación , Permeabilidad , Polímeros/química , Porosidad , Riboflavina/química , Riboflavina/aislamiento & purificación , Solubilidad , Solventes/química
2.
Med Sci Monit ; 27: e933450, 2021 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-34934039

RESUMEN

BACKGROUND In the field of forensic medicine, sex estimation is a critical step in personal identification. Teeth are the hardest tissue and have high temperature resistance and corrosion resistance. In cases such as an airplane crash or the corpse of an unknown person, teeth often play a crucial role in identification. This study applied 3-dimensional technology to obtain odontometrics of permanent maxillary teeth and to examine the sexual dimorphism, finding suitable discriminant indicators to construct appropriate equations for sex estimation. MATERIAL AND METHODS A total of 204 participants (104 men and 100 women) from the Han population in Kashgar were included. Plaster models of their maxillary dentition were obtained to scan and measure through an accepted and commonly used 3-dimensional digital method. Descriptive statistics, t tests, and discriminant analyses were statistically analyzed using IBM SPSS 23.0 software. RESULTS This study showed high intra- and interexaminer reliability (intraclass correlation coefficient >0.950). There were statistically significant sex-related differences (P<0.05), with male values generally being higher for buccolingual distance, mesiodistal distance, intercanine distance, crown area, crown module, crown index, and maxillary canine index. Compared with other measurements, mesiodistal distance and crown area indicator exhibited distinct sexual dimorphism. In addition, several appropriate equations were constructed through different discriminant analyses that could be used to estimate sex in our specific population. CONCLUSIONS Three-dimensional digital technology offers a promising method for odontometry. Combining mesiodistal distance and buccolingual distance of particular teeth or using maxillary canine index in discriminant functions are acceptable auxiliary tools for sex estimation in the forensic field.


Asunto(s)
Imagenología Tridimensional , Maxilar/anatomía & histología , Odontometría/métodos , Adolescente , Adulto , Femenino , Humanos , Imagenología Tridimensional/métodos , Masculino , Caracteres Sexuales , Diente/anatomía & histología , Adulto Joven
3.
Arch Oral Biol ; 159: 105881, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38199116

RESUMEN

OBJECTIVE: Hypoxia-inducible factor-1α (HIF-1α) and its downstream factor, 19 kDa BCL-2 interacting protein 3 (BNIP3), promote cellular autophagy under hypoxic conditions. However, their roles in pulpitis are unclear. Therefore, the changes in inflammatory response and autophagy levels caused by hypoxia during pulpitis were evaluated. Additionally, the regulatory mechanism of HIF-1α/BNIP3 in cellular autophagy in pulpitis was explored. DESIGN: Pulp from dental pulp tissues of healthy individuals and patients with pulpitis (n = 10) were exposed and combined with a low oxygen simulation chamber to construct pulpitis (n = 6), hypoxia (n = 6), and hypoxia+pulpitis (n = 6) rat models. Hematoxylin and eosin and immunohistochemical staining were used to detect the localization and expression levels of HIF-1α, BNIP3, and autophagy marker protein, LC3B. Transmission electron microscopy was used to confirm autophagosome formation. An in vitro hypoxic model of human dental pulp cells was established, and HIF-1α chemical inhibitor 3-(5'-hydroxymethyl-2'-furyl)- 1-benzylindazole (YC-1) was administered. Immunofluorescence and western blotting were used to detect the localization and protein levels of HIF-1α, BNIP3, and LC3B. RESULTS: Autophagy is significantly increased and HIF-1α and BNIP3 are elevated in inflamed dental pulp tissue. Both pulp exposure and hypoxia intervention cause inflammatory reactions in rat dental pulp tissue, accompanied by the autophagy activation. Hypoxia significantly enhances HIF-1α/BNIP3 and autophagy activation. BNIP3 downregulates and autophagy reduces after treatment with YC-1. CONCLUSIONS: In pulpitis, activation of the HIF-1α/BNIP3 signaling pathway driven by hypoxia leads to increased autophagy. This provides a new molecular explanation for autophagy activation in apical periodontitis and new insights into the pathogenesis of the disease.


Asunto(s)
Pulpitis , Animales , Humanos , Ratas , Autofagia , Hipoxia de la Célula , Hipoxia , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Mitocondriales , Proteínas Proto-Oncogénicas/metabolismo
4.
ACS Biomater Sci Eng ; 8(4): 1717-1725, 2022 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-35287434

RESUMEN

Enhancing the stability of the resin-dentin bonding interface via simultaneously improving the antibacterial, mechanical, and adhesive properties of a dental adhesive is the key to prolonging the longevity of dental restoration for caries treatment. Herein, we present the stabilization effect of Ag+- and Zn2+-exchanged zeolite A (denoted as Ag-A and Zn-A, respectively) on the resin-dentin bonding interface. Ag-A and Zn-A zeolites exhibited sustained ion release capability, outstanding biocompatibility to L929 cells (<2 mg/mL), and excellent antibacterial ability to Streptococcus mutans (minimum inhibitory concentration: 100 µg/mL for Ag-A and 200 µg/mL for Zn-A). One-step self-etching adhesives modified by Ag-A, Zn-A, or Ag-/Zn-A (1/1 in weight) zeolites with an ultralow loading of 0.2 wt % exhibited favorable antibacterial activity with the inhibition of biofilm formation by 70.33, 56.47, and 62.54%, respectively. Compared to the control group, Zn-A- and Ag-/Zn-A-modified adhesives significantly increased the wettability properties of the adhesive and the long-term resin-dentin bond strength (by ∼25%) after 5000 thermocycles of aging. The current data demonstrated that the introduction of 0.2 wt % Zn-A or Ag-/Zn-A into the adhesive remarkably enhanced the stability of the resin-dentin bonding interface. Our findings provide a new strategy to modify the dental adhesive for further optimizing the longevity of dental restorations for caries.


Asunto(s)
Cementos de Resina , Zeolitas , Antibacterianos/farmacología , Dentina , Ensayo de Materiales , Cementos de Resina/química , Cementos de Resina/farmacología , Zeolitas/farmacología , Zinc/farmacología
5.
Adv Sci (Weinh) ; 9(29): e2202039, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35988145

RESUMEN

Recent evidence has indicated that overexpression of the epigenetic reader bromodomain-containing protein 4 (BRD4) contributes to a poor prognosis of lung cancers, and the suppression of its expression promotes cell apoptosis and leads to tumor shrinkage. Proteolysis targeting chimera (PROTAC) has recently emerged as a promising therapeutic strategy with the capability to precisely degrade targeted proteins. Herein, a novel style of versatile nano-PROTAC (CREATE (CRV-LLC membrane/DS-PLGA/dBET6)) is developed, which is constructed by using a pH/GSH (glutathione)-responsive polymer (disulfide bond-linked poly(lactic-co-glycolic acid), DS-PLGA) to load BRD4-targeted PROTAC (dBET6), followed by the camouflage with engineered lung cancer cell membranes with dual targeting capability. Notably, CREATE remarkably confers simultaneous targeting ability to lung cancer cells and tumor-associated macrophages (TAMs). The pH/GSH-responsive design improves the release of dBET6 payload from nanoparticles to induce pronounced apoptosis of both cells, which synergistically inhibits tumor growth in both subcutaneous and orthotopic tumor-bearing mouse model. Furthermore, the efficient tumor inhibition is due to the direct elimination of lung cancer cells and TAMs, which remodels the tumor microenvironment. Taken together, the results elucidate the construction of a versatile nano-PROTAC enables to eliminate both lung cancer cells and TAMs, which opens a new avenue for efficient lung cancer therapy via PROTAC.


Asunto(s)
Neoplasias Pulmonares , Factores de Transcripción , Animales , Ratones , Disulfuros/metabolismo , Epigénesis Genética , Glutatión/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/metabolismo , Polímeros , Proteolisis , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Microambiente Tumoral
6.
Arch Oral Biol ; 124: 105059, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33508626

RESUMEN

OBJECTIVE: In orthodontics and prosthodontics fields, it is often necessary to measure the crown dimensions of patient's teeth for further diagnosis and treatment. This study aims to assess the reliability and validity of dental measurements by comparing three-dimensional (3D) measurement of digital model derived from 3D handheld scanner with electronic digital caliper measurement of plaster model, providing a promising technology for dentistry. DESIGN: The mesiodistal diameter, buccolingual diameter and clinical crown height of 2800 teeth were measured on 100 sets of maxillary and mandibular dental plaster models as well as on the corresponding 3D digital models obtained by structured light scanning of the plaster models. Each measurement was performed twice by qualified operators and averaged. Twenty sets of maxillary and mandibular dentition models were randomly selected for intra and inter observer errors. The reliability was evaluated by intraclass correlation coefficient (ICC). Bland-Altman analysis was utilized to evaluate the validity of methods. RESULTS: Excellent reliability (ICC > 0.75) of intra and inter observer on traditional and digital methods were exhibited. Bland-Altman analysis showed the largest difference was the mesiodistal diameter (170/2800), and the smallest (130/2800) was the clinical crown height. Compared with other teeth, buccolingual diameter of incisors and molars, mesiodistal diameter and clinical crown height of premolars and molars displayed relative differences. The mean biases were close to zero, upper and lower 95 % limits of agreement were within 0.5 mm. CONCLUSIONS: Linear measurements obtained from 3D technique are consistent with the conventional method. The 3D technology can be clinically accepted and suitable for dental metrology.


Asunto(s)
Modelos Dentales , Ortodoncia , Humanos , Imagenología Tridimensional , Mandíbula/diagnóstico por imagen , Reproducibilidad de los Resultados
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