Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 46
Filtrar
1.
J Dent ; 147: 105109, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38849053

RESUMEN

OBJECTIVES: The present study aimed to evaluate the effectiveness of bioactive glass (BAG) in preventing dental erosion in primary teeth. METHODS: Enamel and dentin specimens (2 × 2 × 2 mm) were obtained from extracted primary teeth, which were randomly divided into the following groups based on the pretreatments (n = 12): DW (deionized water), NaF (2 % sodium fluoride), 2BAG (2 % BAG), 4BAG (4 % BAG), 6BAG (6 % BAG), and 8BAG (8 % BAG). The specimens were immersed in the respective solutions for 2 min and subjected to in vitro erosive challenges (4 × 5 min/d) for 5 d. The erosive enamel loss (EEL), erosive dentin loss (EDL), and the thickness of the demineralized organic matrix (DOM) were measured using a contact profilometer. The surface microhardness (SMH) was measured, and the percentage of SMH loss (%SMHL) was calculated. The surface morphology and mineral composition were evaluated by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), respectively. RESULTS: After the erosive challenges, the EEL, EDL, and%SMHL of the 2BAG, 4BAG, 6BAG, and 8BAG groups significantly reduced, with the greatest reduction was observed in the 6BAG (EEL: 6.5 ± 0.2 µm;%SMHL in enamel: 12.8 ± 2.6; EDL: 7.9 ± 0.3 µm; %SMHL in dentin: 22.1 ± 2.7) and 8BAG groups (EEL: 6.4 ± 0.4 µm;%SMHL in enamel: 11.0 ± 1.9; EDL: 7.8 ± 0.5 µm; %SMHL in dentin: 22.0 ± 2.5) (P < 0.05). With increasing BAG concentrations, the number of surface deposits containing Ca, P, and Si increased. CONCLUSIONS: 6BAG was the most effective for preventing dental erosion in primary teeth and showed a particularly strong potential for dentin erosion prevention. CLINICAL SIGNIFICANCE: Bioactive glass, especially at a 6 % concentration, has proven effective in reducing erosive tooth wear and surface microhardness loss while also protecting demineralized organic matrix in primary dentin.


Asunto(s)
Esmalte Dental , Dentina , Vidrio , Dureza , Microscopía Electrónica de Rastreo , Fluoruro de Sodio , Espectrometría por Rayos X , Erosión de los Dientes , Diente Primario , Erosión de los Dientes/prevención & control , Humanos , Vidrio/química , Fluoruro de Sodio/uso terapéutico , Propiedades de Superficie , Cerámica/química , Desmineralización Dental/prevención & control , Ensayo de Materiales
2.
Se Pu ; 41(10): 825-834, 2023 Oct.
Artículo en Chino | MEDLINE | ID: mdl-37875405

RESUMEN

Chromatographic column is the core of chromatographic separation, and chromatographic separation material is considered the soul of the chromatographic column. The type and characteristics of the chromatographic separation material directly determine the separation mode and performance of chromatographic columns. The development and preparation of separation materials with novel structures and good separation performance is an ongoing hotspot in chromatography research. Given rapid developments in nanoscience and technology, nanomaterials with unique surface functional groups and large specific surface areas have attracted extensive attention and great interest from researchers in the field of separation science. Carbon dots (CDs), a new type of zero-dimensional fluorescent carbon nanomaterials, have been widely used in bioimaging, light-emitting diodes, sensing, catalysis, drug delivery, and other applications since they were first reported in 2004. These nanomaterials present several advantages over other types of separation materials, including a simple preparation process, low toxicity, easy functionalization, excellent biocompatibility, and photobleaching resistance. In addition, compared with traditional carbon nanomaterials such as graphene and carbon nanotubes, CDs have abundant surface functional groups, nanoscale sizes, and moderate adsorption properties. Hence, when CDs-based new materials are applied as a stationary phase for column chromatography, they can provide rich reaction sites and ensure the uniformity of the chromatographic packing process. The use of CDs can effectively avoid the peak-tailing phenomenon caused by the strong interaction of large π-conjugated systems with some analytes and improve the efficiency of the chromatographic column. As such, these nanomaterials show good application prospects in the field of chromatographic separation. In this review, the development history, classification, and synthesis strategies of CDs are briefly described. We then focus on the development of CDs-based chromatographic separation materials by systematically reviewing the recent advances in the use of CDs-based materials as a stationary phase for high-performance liquid chromatography (including hydrophilic interaction, reversed-phase, mixed-mode, and chiral chromatography), gas chromatography, and capillary electrochromatography, with special emphasis on the preparation methods and applications of various stationary phases. Finally, the development prospects of CDs and future research efforts on these materials are also analyzed and discussed. This review can provide guidance on the rational design and application of new CDs-based chromatographic separation materials.

3.
Se Pu ; 41(10): 823-824, 2023 Oct.
Artículo en Chino | MEDLINE | ID: mdl-37884463
4.
Front Med (Lausanne) ; 10: 1088630, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37305114

RESUMEN

Objective: To systematically compare the bowel cleaning ability, patient tolerance and safety of oral sodium phosphate tablets (NaPTab) and oral polyethylene glycol electrolyte lavage solution (PEGL) to inform clinical decision making. Methods: PubMed, Embase, CBM, WanFang Data, CNKI, and VIP databases were searched for studies that used randomized controlled trials (RCTs) to compare the roles of NaPTab and PEGL in bowel preparation before colonoscopy. Two reviewers independently screened the studies, extracted data, and assessed the risk of bias in the included papers. A meta-analysis was performed using RevMan 5.3 software. Results: A total of 13 RCTs were eligible for inclusion, including 2,773 patients (1,378 and 1,395 cases in the NaPTab and PEGL groups, respectively). Meta-analysis revealed no significant difference in the cleansing quality of the NaPTab and PEGL groups [RR 1.02, 95% CI (0.96-1.08), P = 0.46]. The incidence of nausea was lower in the NaPTab group than in the PEGL group [RR 0.67, 95% CI (0.58-0.76), p < 0.00001]. Patients rated the taste of NaPTab higher than PEGL [RR 1.33, 95% CI (1.26-1.40), P < 0.00001]. Willingness to repeat the treatment was also higher in the NaPTab group than in the PEGL group [RR 1.52, 95% CI (1.28-1.80), P < 0.00001]. Both serum potassium and serum calcium decreased in both groups after the preparation; however, meta-analysis revealed that both minerals decreased more in the NaPTab group than in the PEGL group [MD = 0.38, 95% CI (0.13-0.62), P = 0.006 for serum potassium and MD = 0.41, 95% CI (0.04-0.77), P = 0.03 for serum calcium]. Meanwhile, serum phosphorus increased in both groups after the preparation; however, levels increased more in the NaPTab group than in the PEGL group [MD 4.51, (95% CI 2.9-6.11), P < 0.00001]. Conclusions: While NaP tablets and PEGL were shown to have a similar cleaning effect before colonoscopy, NaP tablets had improved patient tolerance. However, NaP tablets had a strong effect on serum potassium, calcium, and phosphorus levels. For patients with low potassium, low calcium, and renal insufficiency, NaP tablets should be prescribed with caution. For those at high-risk for acute phosphate nephropathy, NaP tablets should be avoided. Given the low number and quality of included studies, these conclusions will require additional verification by large high-quality studies. Systematic review registration: 10.37766/inplasy2023.5.0013, identifier: NPLASY202350013.

5.
J Hematol Oncol ; 16(1): 9, 2023 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-36774506

RESUMEN

BACKGROUND: Selectively targeting leukemia stem cells (LSCs) is a promising approach in treating acute myeloid leukemia (AML), for which identification of such therapeutic targets is critical. Increasing lines of evidence indicate that FBXO22 plays a critical role in solid tumor development and therapy response. However, its potential roles in leukemogenesis remain largely unknown. METHODS: We established a mixed lineage leukemia (MLL)-AF9-induced AML model with hematopoietic cell-specific FBXO22 knockout mice to elucidate the role of FBXO22 in AML progression and LSCs regulation, including self-renewal, cell cycle, apoptosis and survival analysis. Immunoprecipitation combined with liquid chromatography-tandem mass spectrometry analysis, Western blotting and rescue experiments were performed to study the mechanisms underlying the oncogenic role of FBXO22. RESULTS: FBXO22 was highly expressed in AML, especially in MLL-rearranged (MLLr) AML. Upon FBXO22 knockdown, human MLLr leukemia cells presented markedly increased apoptosis. Although conditional deletion of Fbxo22 in hematopoietic cells did not significantly affect the function of hematopoietic stem cells, MLL-AF9-induced leukemogenesis was dramatically abrogated upon Fbxo22 deletion, together with remarkably reduced LSCs after serial transplantations. Mechanistically, FBXO22 promoted degradation of BACH1 in MLLr AML cells, and overexpression of BACH1 suppressed MLLr AML progression. In line with this, heterozygous deletion of BACH1 significantly reversed delayed leukemogenesis in Fbxo22-deficient mice. CONCLUSIONS: FBXO22 promotes MLLr AML progression by targeting BACH1 and targeting FBXO22 might be an ideal strategy to eradicate LSCs without influencing normal hematopoiesis.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico , Proteínas F-Box , Leucemia Mieloide Aguda , Receptores Citoplasmáticos y Nucleares , Animales , Humanos , Ratones , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Ciclo Celular , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Células Madre Hematopoyéticas/metabolismo , Leucemia Mieloide Aguda/patología , Ratones Noqueados , Proteína de la Leucemia Mieloide-Linfoide/metabolismo , Células Madre Neoplásicas/patología , Receptores Citoplasmáticos y Nucleares/metabolismo
6.
Dent Mater ; 38(12): e297-e307, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36192276

RESUMEN

OBJECTIVE: The aim of the present study was to evaluate the in situ/in vivo effect of quercetin on dentin erosion and abrasion. METHODS: Human dentin blocks (2 × 2 × 2 mm) were embedded and assigned to 6 groups: 75 µg/mL, 150 µg/mL and 300 µg/mL quercetin (Q75, Q150, Q300); 120 µg/mL chlorhexidine (CHX, positive control); and deionized water and ethanol (the negative controls). The specimens were treated with the respective solutions for 2 min and then subjected to in situ/in vivo erosive/abrasive challenge for 7 d as follows: in vivo erosion 4 times a day and then in vivo toothbrush abrasion after the first and last erosive challenges of each day. Dentin loss was assessed by profilometry. An additional dentin specimen was used to evaluate the penetration depth of quercetin into dentin by tracking the spatial distribution of its characteristic Raman peak. Moreover, dentin blocks (7 × 1.7 × 0.7 mm) were used to detect the impact of quercetin on dentin-derived matrix metalloproteinase (MMP) inhibition by in situ zymography, and the inhibition percentage (%) was calculated. Additionally, the potential collagen crosslinking interactions with quercetin were detected by Raman spectroscopy, and the crosslinking degree was determined with a ninhydrin assay. Fully demineralized dentin beams (0.5 × 0.5 × 10 mm) were used to evaluate the impact of quercetin on the mechanical properties of dentin collagen fibre by the ultimate micro-tensile strength test (µUTS). The data were analysed by one-way analysis of variance and Tukey's test (α = 0.05). RESULTS: Compared to the negative controls, all treatment solutions significantly reduced dentin loss. The dentin loss of Q150 and Q300 was significantly less than that of CHX (all P < 0.05). The amount of quercetin decreased with increasing dentin depth, and the maximum penetration depth was approximately 25-30 µm. In situ zymography showed that quercetin significantly inhibited the activities of dentin-derived MMPs. The inhibitory percentages of Q75 and Q150 were significantly lower than that of CHX (all P < 0.05), but no significant difference was found between Q300 and CHX (P = 0.58). The collagen crosslinking interactions with quercetin primarily involved hydrogen bonding and the degree of crosslinking increased in a concentration-dependent manner. Statistically significant increases in µUTS values were observed for demineralized dentin beams after quercetin treatment compared with those of the control treatments (all P < 0.05). SIGNIFICANCE: This study provides the first direct evidence that quercetin could penetrate approximately 25-30 µm into dentin and further prevent dentin erosion and abrasion by inhibiting dentin-derived MMP activity as well as crosslinking collagen of the demineralized organic matrix.


Asunto(s)
Inhibidores de la Metaloproteinasa de la Matriz , Erosión de los Dientes , Humanos , Inhibidores de la Metaloproteinasa de la Matriz/farmacología , Erosión de los Dientes/prevención & control , Quercetina/farmacología , Dentina , Metaloproteinasas de la Matriz , Colágeno
7.
Chemosphere ; 308(Pt 2): 136388, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36088963

RESUMEN

Remediation of soil contaminated by mixed heavy metals and metalloids has been a major challenge in the global environmental field. To address this critical issue, we tested a new technology for simultaneous immobilization of lead (Pb) and arsenic (As) in a field contaminated soil using a microwave-assisted FeSO4·7H2O treatment process. The process was able to rapidly reduce the TCLP-based leachability of Pb from 12.74 to 0.1 mg L-1 and As from 2.704 to 0.002 mg L-1 (MW power = 800 W, Irradiation time = 20 min, and FeSO4·7H2O = 4 wt%). The effects of FeSO4·7H2O dosage, microwave power, and irradiation time were determined and optimized. After 365 days of curing under atmospheric conditions, the TCLP-leached concentration of Pb and As in the treated soil remained below the regulatory limits of 0.1 and 0.002 mg L-1, respectively. The microwave irradiation promoted the formation of insoluble PbSO4(s) and Fe3(AsO4)2·8H2O(s), resulting in the long-term stability of Pb and As in the soil. The technology offers an effective alternative for remediation of Pb- and/or As-contaminated soil and groundwater.


Asunto(s)
Arsénico , Metales Pesados , Contaminantes del Suelo , Arsénico/análisis , Compuestos Ferrosos , Plomo , Microondas , Suelo , Contaminantes del Suelo/análisis
8.
J Mech Behav Biomed Mater ; 135: 105476, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36179613

RESUMEN

This in vitro study aimed to investigate the effect of quercetin pretreatment on the bond strength of bleached dentin. Human dentin blocks (2 × 2 × 1 mm) were prepared and randomly divided into 5 groups (n = 16): deionized water pretreatment + no bleaching treatment (DNB); deionized water pretreatment + bleaching treatment (DYB); 75 µg/mL quercetin pretreatment + bleaching (Q75B); 150 µg/mL quercetin pretreatment + bleaching (Q150B); and 300 µg/mL quercetin pretreatment + bleaching (Q300B). The surfaces of superficial dentin (bonding surfaces) were treated with the respective solutions for 2 min, and then the surfaces opposite to the bonding surfaces (near pulp, bleaching surfaces) were subjected to bleaching treatment with 40% hydrogen peroxide (Ultradent, USA) for two 15-min sessions (groups DYB, Q75B, Q150B, and Q300B). After the bleaching procedure, the bonding surfaces were bonded with resin cements (Panavia V5, Kuraray, Japan). The bonded specimens were then divided into 2 subgroups (n = 8): the aging group (subgroup T), which was subjected to 10,000 thermocycles, and the nonaging group (subgroup N), which was not subjected to thermocycling. The microshear bond strength (µSBS) was obtained using a universal testing machine (AGS-X, Shimadzu, Tokyo, Japan). Additional dentin blocks (5 × 5 × 1 mm) were prepared and treated the same as the groups DYB, Q75B, Q150B, and Q300B (n = 8) to evaluate the color change, defined as groups CCDYB, CCQ75B, CCQ150B, and CCQ300B, respectively. Color evaluation was performed using a spectrophotometer (Vita Easyshade Advance 4.0, Vident, USA) to obtain a baseline and again at the end of the bleaching treatment. The data were analyzed via two-way analysis of variance (ANOVA) and Tukey's post-hoc test (α = 0.05). For the immediate bond strength, the specimens in the groups Q75B, Q150B, and Q300B showed significantly higher µSBS values than those in the group DYB (all P < 0.05). No significant differences in the µSBS values were found among the groups Q75B, Q150B, Q300B, and DNB, respectively (all P > 0.05). For the aged bond strength, both the groups Q150B and Q300B exhibited significantly higher µSBS values than groups DYB and DNB (all P < 0.05), whereas no significance differences were found between groups Q150B and Q300B (P = 1.00) or between the groups DYB and DNB (P = 1.00). No significant differences were observed in the △E values among all the groups tested (P = 0.80). Therefore, the application of quercetin for 2 min prior to the bleaching procedure preserved the immediate bond strength and improved the aged bond strength of bleached dentin while maintaining the effectiveness of bleaching.


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos de Resina , Resinas Compuestas/análisis , Análisis del Estrés Dental , Dentina/química , Humanos , Peróxido de Hidrógeno , Quercetina/análisis , Quercetina/farmacología , Cementos de Resina/análisis , Resistencia al Corte , Agua/farmacología
9.
Sensors (Basel) ; 22(11)2022 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-35684592

RESUMEN

We proposed a novel temperature-compensated multi-point strain sensing system based on cascaded FBG and optical FMCW interferometry. The former is used for simultaneous sensing of temperature and strain, and the latter is used for position information reading and multiplexing. In the experiment, a narrow linewidth laser with continuous frequency-sweeping was used as the light source. After demodulating the beat-frequency signal, the link information of the 16 m fiber was obtained, and the measured result was identical to the actual position. The measurement accuracy reached 50.15 mm, and the dynamic range was up to 22.68 dB. Meanwhile, we completed the sensing experiments for temperature range from 20 °C to 90 °C and strain range from 0 µÎµ to 7000 µÎµ. The sensitivity of the sensing system to temperature was 10.21 pm/°C, the sensitivity and accuracy to strain were as high as 1.163 pm/µÎµ and 10 µÎµ, respectively. Finally, the measured strain and temperature values were obtained using the sensing matrix. The sensing system has important practical significance in the field of quasi-distributed strain measurement.

10.
J Prosthodont Res ; 66(4): 530-537, 2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-34853237

RESUMEN

PURPOSE: This study systematically reviewed the literature to compare the bond strength of resin composites with that of zirconia-reinforced lithium silicate (ZLS) and lithium disilicate (LD). STUDY SELECTION: This review was structured based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) statement. This study was registered at the International Prospective Register of Systematic Reviews (CRD42021256900). Studies were searched via PubMed, Web of Science, and Google Scholar databases without language or publication year limits. In vitro studies that evaluated the bond strength of the resin composites to ZLS and LD were included. The risk of bias in all the included articles was evaluated. Statistical analyses were performed using the Review Manager software (version 5.3, Cochrane Collaboration, Oxford, UK). RESULTS: Of the 90 potentially related articles, the full texts of 16 articles were evaluated after screening. Finally, seven studies were included in the qualitative synthesis and meta-analysis. All the studies presented a medium risk of bias. The results showed no significant difference in bond strength between the ZLS and LD groups (P = 0.94, mean difference=0.08, and 95% confidence interval=-1.93 to 2.10). However, a significant difference was found in the subgroup analysis considering different types of aging treatments (P = 0.0008) and different types of bond strength tests (P < 0.00001). CONCLUSION: The bond strength of resin composites was found to be similar to that of ZLS and LD, but different aging treatments and bond strength tests exhibited varying effects on the bond strength.


Asunto(s)
Litio , Cementos de Resina , Cerámica/química , Resinas Compuestas , Porcelana Dental/química , Análisis del Estrés Dental , Ensayo de Materiales , Silicatos , Propiedades de Superficie , Circonio/química
11.
Se Pu ; 39(12): 1347-1354, 2021 Dec.
Artículo en Chino | MEDLINE | ID: mdl-34812007

RESUMEN

Clenbuterol enantiomers differ greatly in their bioactivities. By optimizing the conditions for chromatographic separation and method validation, ultra-performance convergence chromatography (UPC2) was adopted to separate the enantiomers of clenbuterol. Standard solutions of (+)-clenbuterol and (-)-clenbuterol were stored at -18 ℃ for 1, 3, 5, 7, 14, 30, and 60 d, and then, their stability was monitored. The impacts of different chromatographic columns, cosolvents, system backpressure, and chromatographic column temperature on the separation of the two enantiomers were investigated. Acquity Trefoil AMY1 (150 mm×3.0 mm, 2.5 µm) was used for separation, and CO2-0.5% (v/v) ammonium acetate was used as the mobile phase. Gradient elution at a flow rate of 2.0 mL/min was adopted. The detection wavelength was set to 241 nm, and the injection volume was set to 10 µL. The backpressure was set to 13.8 MPa, and the column temperature was maintained at 40 ℃. The two enantiomers showed good linear relationships in the range of 1.0 to 20.0 mg/L with correlation coefficients greater than 0.9997. The limits of detection (LODs, S/N=3) of (+)-clenbuterol and (-)-clenbuterol were both 0.5 mg/L. The relative standard deviation (RSD, n=6) for the peak area of the 10.0 mg/L mixed standard working solution with six replicate injections ranged from 0.65% to 0.76%. The effectiveness and practicability of this method were demonstrated by using it to detect standard clenbuterol racemate. The (+)-clenbuterol and (-)-clenbuterol contents were 5.6 mg/L and 5.5 mg/L, respectively, in the standard clenbuterol racemates, as determined by the external standard method of quantification. The detection results suggested that the content ratio of (+)-clenbuterol and (-)-clenbuterol was close to 1.02∶1.00, which is consistent with the literature data. The established method has the advantages of rapid analysis, good separation effect, and low consumption of organic solvents, and it is suitable for the separation of clenbuterol enantiomers. This method can also provide technical support for the separation of other chiral drugs, analysis of the effects of chiral drugs, and assessment of product quality.


Asunto(s)
Clenbuterol , Cromatografía Líquida de Alta Presión , Solventes , Estereoisomerismo
12.
Clin Oral Investig ; 24(12): 4169-4183, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33052542

RESUMEN

OBJECTIVE: Controversy exists regarding the effectiveness of delayed toothbrushing in decreasing erosive tooth wear (ETW). The purpose of this systematic review and meta-analysis was to assess the effects of delayed toothbrushing on ETW. MATERIALS AND METHODS: This systematic review and meta-analysis was conducted according to the PRISMA statement and registered in PROSPERO (CRD42020200463). PubMed, Embase, and Web of Science databases were systematically searched with no publication year limits. Screening and data extraction were performed independently by two reviewers. In situ and in vitro studies comparing ETW after delayed and immediate toothbrushing following an erosive attack were included. Review Manager software 5.3 (The Cochrane Collaboration, Oxford, UK) was used for statistical analyses. Heterogeneity was assessed with the Cochran Q test and I2 statistics. RESULTS: Of the 565 potentially relevant studies, 26 full-text articles were assessed for eligibility. Twelve articles were included in the systematic review, and 11 were included in the qualitative analyses. No significant difference in the ETW of human enamel was observed between delayed and immediate toothbrushing (P = 0.13), whereas significantly less ETW of bovine enamel was observed after delayed toothbrushing (P < 0.001). No significant difference in the ETW of bovine dentin was observed between delayed and immediate toothbrushing (P = 0.34). Studies on human dentin were not available. Subgroup analyses revealed a significant contribution of the use of fluoridated toothpaste to decreasing the ETW of human enamel after erosion and toothbrush abrasion (P = 0.02). CONCLUSIONS: Bovine and human teeth behaved differently in response to erosion and toothbrush abrasion. Delayed toothbrushing after an erosive attack was not effective at decreasing the ETW of human enamel compared to immediate toothbrushing, whereas it was effective at decreasing the ETW of bovine enamel. CLINICAL RELEVANCE: Delayed toothbrushing alone after the consumption of erosive foodstuffs or beverages is not capable of preventing erosive enamel wear.


Asunto(s)
Abrasión de los Dientes , Erosión de los Dientes , Desgaste de los Dientes , Animales , Bebidas , Bovinos , Esmalte Dental , Humanos , Abrasión de los Dientes/etiología , Abrasión de los Dientes/prevención & control , Erosión de los Dientes/prevención & control , Desgaste de los Dientes/prevención & control , Cepillado Dental
13.
J Mech Behav Biomed Mater ; 110: 103903, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32957208

RESUMEN

This in situ/in vivo study aimed to evaluate the effects of erosion on the surface microhardness, substance loss, and surface roughness of CAD/CAM restorative materials and human enamel. This study used a 2-treatment (14 days each) crossover design with 8 healthy volunteers. Each volunteer wore an intraoral appliance containing 3 CAD/CAM restorative material specimens [IPS e.max CAD, Lava Ultimate CAD/CAM Restorative, and a poly (methyl methacrylate) (PMMA) block for CAD/CAM] and 1 human enamel specimen. The specimens were subjected to in vivo erosion cycles by rinsing with 150 ml of cola drink (4 × 5 min/day) for 14 days. The surface microhardness, substance loss, and surface roughness of the specimens were measured at baseline (T1), day 7 (T2) and day 14 (T3). The data were statistically analyzed using repeated measures ANOVA and Tukey's test (α = 0.05). After erosion, significant increases in substance loss and surface roughness were observed for enamel, though the surface roughness and substance profile of the tested restorative materials remained unchanged. Erosion significantly decreased the surface microhardness of all materials. For IPS e.max and Lava Ultimate, a significantly higher percentage of surface microhardness loss (%SMHl) was found at T3 than at T2, while no significant difference was found between T2 and T3 for enamel and the PMMA block. In conclusion, CAD/CAM restorative materials showed smaller changes in surface roughness and the surface profile than human enamel after in situ/in vivo erosion. However, CAD/CAM restorative materials and human enamel showed similar changes in surface microhardness after in situ/in vivo erosion.


Asunto(s)
Bebidas Gaseosas , Diseño Asistido por Computadora , Cerámica , Humanos , Ensayo de Materiales , Propiedades de Superficie
14.
Dent Mater ; 36(11): 1430-1436, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32928560

RESUMEN

OBJECTIVE: The aim of the present study was to evaluate the effect of quercetin on the acid resistance of human dentin through both laboratory and clinical studies. METHODS: Two hundred and twelve dentin blocks (2 mm × 2 mm × 2 mm) were prepared and used. For the laboratory study, dentin specimens were randomly divided into 8 groups (n = 12): deionized water, ethanol, 1.23 × 104 µg/ml sodium fluoride (NaF), 120 µg/ml chlorhexidine, 183.2 µg/ml epigallocatechin gallate (EGCG), and 75 µg/ml, 150 µg/ml, and 300 µg/ml quercetin (Q75, Q150, and Q300). The specimens were treated with the respective solutions for 2 min and then subjected to in vitro erosion (4 cycles/d for 7 d). The surface microhardness loss (%SMHl), erosive dentin wear, and surface morphology were evaluated and compared. For the impact on MMP inhibition, the release of crosslinked carboxyterminal telopeptide of type I collagen (ICTP) and the thickness of the demineralized organic matrix (DOM) were measured using additional dentin specimens. For the clinical study, the specimens were treated with NaF or Q300 for 2 min and then subjected to in vivo erosion (4 cycles/d for 7 d). The %SMHl and erosive dentin wear of the specimens were measured to determine whether quercetin similarly inhibits erosion in situ. RESULTS: The quercetin-treated group had a significantly lower %SMHl and erosive dentin wear than any other group, and the effect was concentration-dependent in vitro (P < 0.05). Dentin treated with quercetin produced significantly less ICTP and had a thicker DOM than the control dentin (P < 0.05). After in vivo erosion, the %SMHl and erosive dentin wear of the Q300 group were significantly lower than those of the control group (P < 0.05). SIGNIFICANCE: The application of quercetin was shown, for the first time, to increase the acid resistance of human dentin, possibly through MMP inhibition and DOM preservation.


Asunto(s)
Erosión de los Dientes , Dentina , Fluoruros , Humanos , Laboratorios , Quercetina
16.
BMC Oral Health ; 20(1): 110, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-32295583

RESUMEN

BACKGROUND: To assess the knowledge of and attitudes towards erosive tooth wear among dental, medical, and non-medical university students of two Chinese universities. METHODS: A questionnaire containing 15 questions on knowledge of erosive tooth wear and 10 questions on attitudes towards erosive tooth wear was designed, and its psychometric properties (reliability and validity) were analysed in a pilot study (n = 120 students). The following 3 groups of university students (n = 635) were recruited based on a convenience sampling technique and were distributed the questionnaire via an online survey system: dental students (DSs), medical students (MSs), and non-medical students (NSs). Differences in the scores between groups and genders were analysed by one-way analysis of variance (ANOVA). The Pearson correlation coefficient was used to determine the association between the knowledge and attitude scores (P < 0.05). RESULTS: The questionnaire was found to be reliable, valid and reproducible. A total of 435 students participated in this study (response rate: 69.6%). The knowledge score of the DSs (11.5 ± 3.4) was significantly higher than those of the NSs (5.5 ± 4.0) and MSs (6.1 ± 4.0) (P < 0.001). The attitude score of the DSs (45.2 ± 6.5) was significantly higher than those of the NSs (41.1 ± 6.9) and MSs (41.8 ± 6.4) (P < 0.001). The majority of DSs expressed attitudes that were more accurate and positive than those expressed by the other 2 groups. The attitude score was positively correlated with the knowledge score (r = 0.237, P < 0.001). CONCLUSIONS: Dental students had more accurate knowledge of and more positive attitudes towards erosive tooth wear than medical and non-medical students. In this population, a positive correlation was established between knowledge of and attitudes towards erosive tooth wear.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Estudiantes/psicología , Erosión de los Dientes , Desgaste de los Dientes , Adolescente , Adulto , Pueblo Asiatico , Estudios Transversales , Femenino , Humanos , Masculino , Proyectos Piloto , Reproducibilidad de los Resultados , Estudiantes/estadística & datos numéricos , Encuestas y Cuestionarios , Universidades
17.
Blood ; 135(17): 1472-1483, 2020 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-32315388

RESUMEN

Internal tandem duplication (ITD) mutations within the FMS-like receptor tyrosine kinase-3 (FLT3) can be found in up to 25% to 30% of acute myeloid leukemia (AML) patients and confer a poor prognosis. Although FLT3 tyrosine kinase inhibitors (TKIs) have shown clinical responses, they cannot eliminate primitive FLT3-ITD+ AML cells, which are potential sources of relapse. Therefore, elucidating the mechanisms underlying FLT3-ITD+ AML maintenance and drug resistance is essential to develop novel effective treatment strategies. Here, we demonstrate that FLT3 inhibition induces histone deacetylase 8 (HDAC8) upregulation through FOXO1- and FOXO3-mediated transactivation in FLT3-ITD+ AML cells. Upregulated HDAC8 deacetylates and inactivates p53, leading to leukemia maintenance and drug resistance upon TKI treatment. Genetic or pharmacological inhibition of HDAC8 reactivates p53, abrogates leukemia maintenance, and significantly enhances TKI-mediated elimination of FLT3-ITD+ AML cells. Importantly, in FLT3-ITD+ AML patient-derived xenograft models, the combination of FLT3 TKI (AC220) and an HDAC8 inhibitor (22d) significantly inhibits leukemia progression and effectively reduces primitive FLT3-ITD+ AML cells. Moreover, we extend these findings to an AML subtype harboring another tyrosine kinase-activating mutation. In conclusion, our study demonstrates that HDAC8 upregulation is an important mechanism to resist TKIs and promote leukemia maintenance and suggests that combining HDAC8 inhibition with TKI treatment could be a promising strategy to treat FLT3-ITD+ AML and other tyrosine kinase mutation-harboring leukemias.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Resistencia a Antineoplásicos , Proteína Forkhead Box O1/metabolismo , Histona Desacetilasas/metabolismo , Leucemia Mieloide Aguda/patología , Proteínas Represoras/metabolismo , Proteína p53 Supresora de Tumor/antagonistas & inhibidores , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidores , Animales , Apoptosis , Biomarcadores de Tumor/genética , Proliferación Celular , Proteína Forkhead Box O1/genética , Regulación Neoplásica de la Expresión Génica , Histona Desacetilasas/genética , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones SCID , Mutación , Pronóstico , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Represoras/genética , Secuencias Repetidas en Tándem , Células Tumorales Cultivadas , Regulación hacia Arriba , Ensayos Antitumor por Modelo de Xenoinjerto
18.
J Dent ; 95: 103318, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32169479

RESUMEN

OBJECTIVES: To evaluate the short-term effects of stain-causing beverages on the effectiveness of in-office tooth bleaching. METHODS: Participants were recruited and randomly divided into 3 groups based on beverages used for rinsing during and after the bleaching procedure: group N (tap water, control group), group C (coffee), and group T (tea). Participants were instructed to rinse with the respective solutions for 30 s, 4 times daily for 4 weeks. All participants received two in-office bleaching treatment sessions with 40 % hydrogen peroxide (Opalescence BOOST PF 40 %, Ultradent); the sessions were separated by a 1-week interval. Tooth colour was assessed using a spectrophotometer (Easyshade, Vita ZahnFabrik) before the bleaching procedure (T0), immediately after the first session of bleaching (T1), immediately after the second session of bleaching (T2), as well as one week (T3) and three weeks after (T4) the end of bleaching. Tooth sensitivity (TS) was ranked using a numerical rating scale (NRS) and a visual analogue scale (VAS) at different time points. RESULTS: No significant difference in the whiteness index (W), △E, △a* and △b* values among the 3 groups was observed at any time interval (P for all > 0.05). At T4, the △L* value in group C was significantly lower than that in groups T and N (P = 0.022 and P = 0.001, respectively), though no significant difference in △L* values was observed among the 3 groups at T1 (P = 0.402), T2 (P = 0.643) and T3 (P = 0.177). Additionally, no significant difference was found in the TS values among the 3 groups at any of the evaluation time points (P for all > 0.05). CONCLUSIONS: Exposure to coffee or tea during the bleaching treatment period did not affect the effectiveness of the treatment. However, exposure to coffee after the bleaching treatment did affect the effectiveness of the treatment. Exposure to stain-causing beverages did not affect the bleaching-induced TS (ClinicalTrials.gov Identifier: NCT03933527). CLINICAL SIGNIFICANCE: The consumption of coffee or tea during tooth bleaching may not interfere with the colour change produced by the treatment. However, clinicians should advise their patients to refrain from, at least to some extent, consuming coffee after the bleaching procedure to maintain the effectiveness of the treatment.


Asunto(s)
Bebidas , Sensibilidad de la Dentina , Blanqueadores Dentales , Blanqueamiento de Dientes , Colorantes , Humanos , Peróxido de Hidrógeno
19.
Cancer Biomark ; 27(4): 433-443, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31929141

RESUMEN

Faced with the increasing colorectal cancer (CRC) cases, the interrogation of pivotal molecules in CRC appears to be vitally important. Long non-coding RNAs (lncRNAs) are well-known regulators of gene expression at transcriptional, post-transcriptional or epigenetic level, among which the competing endogenous RNA (ceRNA) network is a common way that lncRNAs exert their properties. The current study aimed to provide a new insight into improving the outcomes of CRC patients. Our study detected that ELFN1-AS1 expression was elevated in CRC tissues and cells, and ELFN1-AS1 upregulation was correlated with poor prognosis of CRC sufferers. Besides, it was viewed that ELFN1-AS1 knockdown impeded the proliferation and migration abilities as well as activated the apoptosis ability of CRC cells. In subsequence, mechanism assays also displayed that ELFN1-AS1 targeted miR-4644 to augment TRIM44 level. Finally, rescue experiments confirmed that TRIM44 took part in the ELFN1-AS1-medatied promotional influences on CRC cells proliferation and migration. In conclusion, ELFN1-AS1 exerted pro-proliferation, anti-apoptosis and pro-migration functions on CRC cells by acting as a sponge of miR-4644 to increase TRIM44 expression at mRNA and protein level, providing an additional molecule responsible for the carcinogenesis and progression for CRC.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , MicroARNs/metabolismo , Proteínas del Tejido Nervioso/genética , ARN sin Sentido/metabolismo , ARN Largo no Codificante/metabolismo , Proteínas de Motivos Tripartitos/metabolismo , Apoptosis/fisiología , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Neoplasias Colorrectales/genética , Bases de Datos Genéticas , Progresión de la Enfermedad , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , MicroARNs/genética , ARN sin Sentido/genética , ARN Largo no Codificante/genética , Transducción de Señal , Proteínas de Motivos Tripartitos/genética
20.
Se Pu ; 37(11): 1173-1178, 2019 Nov 08.
Artículo en Chino | MEDLINE | ID: mdl-31642269

RESUMEN

A rapid screening method was developed to determine sibutramine and five derivatives in health food by high performance liquid chromatography-quadrupole/electrostatic orbitrap high-resolution mass spectrometry (HPLC-Q/Orbitrap HRMS). The sample was extracted with methanol via ultrasonic-assisted extraction coupled with high-speed centrifugation. Separation was performed on a Hypersil Gold column (100 mm×2.1 mm, 3 µm) by gradient elution with methanol/water (containing 0.15%(v/v) formic acid) as the mobile phase. The positive full mass scan/date-dependent MS2 (Full MS/dd-MS2) mode was used during MS detection, and quantification was achieved by resolution of the precursor mass. The analytes in the sample were separated, and accurate mass and MS2 fragment ions were simultaneously attained within 8 min. The results indicated that the obtained mass accuracy errors of the six analytes were less than 1×10-6. Good linearities were obtained in the range of 0.5-20.0 µg/L, and all correlation coefficients were higher than 0.999. The limits of quantification were 25 µg/kg and the recoveries were in the range of 93.5%-103.5% with relative standard deviations of 1.5%-7.7%. This simple-pretreatment, rapid, accurate, high-sensitivity, and high-selectivity method can be used in the rapid screening and quantitative analysis of sibutramine and its derivatives in health food.


Asunto(s)
Ciclobutanos/análisis , Análisis de los Alimentos/métodos , Cromatografía Líquida de Alta Presión , Espectrometría de Masas , Electricidad Estática
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...