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1.
Shanghai Kou Qiang Yi Xue ; 33(1): 36-39, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38583022

RESUMO

PURPOSE: To study the effect of different cleaning methods on the shear bond strength of self-adhesive resin cement to saliva-contaminated high translucency zirconia and surface wettability. METHODS: Eighty zirconia specimens were randomly divided into 5 groups (n=16), i.e., control group(not contaminated), 75% ethanol group,cleaning paste group,airborne-particle abrasion group, and atmospheric pressure cold plasma group. The contact angles was measured, shear bond strength were examined, and fracture types were determined. SPSS 26.0 software package was used for statistical analysis of the data. RESULTS: The atmospheric pressure cold plasma group produced the lowest contact angle(P<0.05). The shear bond strength of the airborne-particle abrasion group, the cleaning paste group and the atmospheric pressure cold plasma group respectively were similar to the control group without significant difference(P>0.05), while those were significantly higher than 75% ethanol group(P<0.05). The mixed fracture mode of the atmospheric pressure cold plasma group evidently increased. CONCLUSIONS: Airborne-particle abrasion, cleaning paste and atmospheric pressure cold plasma overcome the effects of saliva contamination, producing the shear bond strength to zirconia similar to the control group. The atmospheric pressure cold plasma improves hydrophilicity of high translucency zirconia significantly.


Assuntos
Colagem Dentária , Gases em Plasma , Molhabilidade , Propriedades de Superfície , Cimentos de Resina , Zircônio/química , Etanol , Teste de Materiais , Resistência ao Cisalhamento , Análise do Estresse Dentário
2.
Angew Chem Int Ed Engl ; 63(8): e202318856, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38169084

RESUMO

Chirality, with its intrinsic symmetry-breaking feature, is frequently utilized in the creation of acentric crystalline functional materials that exhibit intriguing optoelectronic properties. On the other hand, the development of chiral crystals from achiral molecules offers a solution that bypasses the need for enantiopure motifs, presenting a promising alternative and thereby expanding the possibilities of the self-assembly toolkit. Nevertheless, the rational design of achiral molecules that prefer spontaneous symmetry breaking during crystallization has so far been obscure. In this study, we present a series of six achiral molecules, demonstrating that when these conformationally flexible molecules adopt a cis-conformation and engage in multiple non-covalent interactions along a helical path, they collectively self-assemble into chiral superstructures consisting of single-handed supramolecular columns. When these homochiral supramolecular columns align in parallel, they form polar crystals that exhibit intense luminescence upon grinding or scraping. We therefore demonstrate our molecular design strategy could significantly increase the likelihood of symmetry breaking in achiral molecular synthons during self-assembly, offering a facile access to novel chiral crystalline materials with unique optoelectronic properties.

3.
Dent Mater J ; 41(6): 896-904, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36244735

RESUMO

This study aims to evaluate the effects of cold atmospheric plasma (CAP) treatment on the bonding of resin cement to high-translucency zirconia. Zirconia specimens were subjected to different treatments: no treatment (ZrT), 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing primer (ZrT-M), alumina particle air-abrasion with/without MDP-containing primer (ZrT-AM/ZrT-A), CAP with/without MDP-containing primer (ZrT-PM/ZrT-P). The surface topography, wettability, and chemical composition were evaluated. The shear bond strength (SBS) was tested before and after thermocycling. CAP did not alter the morphology, increased the wettability, and decreased the carbon/oxygen ratio of zirconia surface. The SBSs of ZrT-PM and ZrT-P were significantly higher than the other groups. After thermocycling, ZrT-A, ZrT-M, ZrT-AM, and ZrT-P showed comparable SBSs, all of which were lower than ZrT-PM. It was concluded that CAP improved the bonding performance of high-translucency zirconia without damaging its surface. The combination of CAP with MDP further enhanced the bond strength and may enable durable bonding.


Assuntos
Colagem Dentária , Gases em Plasma , Teste de Materiais , Propriedades de Superfície , Zircônio/química , Cimentos de Resina/química , Cerâmica , Resistência ao Cisalhamento , Metacrilatos/química
4.
Ann Palliat Med ; 10(6): 6948-6956, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34237989

RESUMO

OBJECTIVE: This article summarizes the research progress on the association of dietary habits with esophageal cancer (EC), with the aim of gaining a better understanding of lifestyle, dietary, and drug-related risk factors as well as protective factors of EC. BACKGROUND: EC is one of the most common malignant cancers and has a high mortality rate. Evidence has suggested that dietary habits are closely related to EC. Several researches refer to the issue of the relationship between dietary habits and EC, but rare of them summary systematically and comprehensively. It is of great importance to study the role of dietary habits in the etiology of EC for the prevention and treatment of this disease. METHODS: We searched the China National Knowledge Infrastructure (CNKI), PubMed, Medline and EMBASE databases to identify studies on the association of dietary habits with EC published between the databases' dates of inception and March 2021. CONCLUSIONS: This comprehensive review summarizes the state-of-the-art research findings on the association between dietary habits and EC, with the literature we obtained revealing that dietary habits have been increasingly regarded as potential etiologies or protective factors of EC, which reinforce the importance of suitable planning of interventions to reduce the burden of this disease among the population.


Assuntos
Adenocarcinoma , Carcinoma de Células Escamosas , Neoplasias Esofágicas , China , Neoplasias Esofágicas/etiologia , Comportamento Alimentar , Humanos , Fatores de Risco
6.
Eur J Med Chem ; 216: 113336, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33725657

RESUMO

P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) is a phenomenon in which cells become resistant to structurally and mechanistically unrelated drugs resulting in low intracellular drug concentrations. It is one of the noteworthy problems in malignant tumor clinical therapeutics. So P-gp protein is one of the ideal targets to solve MDR. Based on the lead compound 5m obtained from our previous work, a series of furan derivatives featuring alkyl-substituted phenols and 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline were designed and synthesized as reversal agents against P-gp in this paper. Compound 16 containing isopropoxy possessed good potency against P-gp mediated MDR in MCF-7/ADR (IC50 (doxorubicin) = 0.73 µM, RF = 69.6 with 5 µM 16 treated). Western blot results and Rh123 accumulation assays showed that 16 effectively inhibited P-gp efflux function but not its expression. The preliminary structure-activity relationship and docking studies demonstrated that compound 16 would be a potential P-gp inhibitor. Most worthy of mention is that compound 16 has achieved satisfactory results in combination with a variety of anti-tumor drugs, such as doxorubicin, paclitaxel, and vincristine. This study forwards a hopeful P-gp inhibitor for withstanding malignant tumor cell with multidrug resistance setting the basis for further studies.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Antineoplásicos/farmacologia , Desenho de Fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Furanos/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/farmacologia , Furanos/metabolismo , Furanos/farmacologia , Humanos , Simulação de Acoplamento Molecular , Paclitaxel/farmacologia , Relação Estrutura-Atividade , Tetra-Hidroisoquinolinas/química , Tetra-Hidroisoquinolinas/metabolismo , Tetra-Hidroisoquinolinas/farmacologia
7.
J Dent ; 76: 40-45, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29857075

RESUMO

OBJECTIVE: This in situ study aimed to evaluate the protective effect of Tooth Mousse (GC) containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on human enamel erosion and to compare the difference in erosion between the anteriorly and posteriorly positioned human enamel. METHODS: This study used a 2-treatment (7 days each) crossover design with 12 healthy volunteers wearing intraoral appliances. Each appliance contained 4 human enamel specimens positioned on the buccal surfaces of the volunteers' maxillary central incisors and first molars. The specimens were intraorally treated withTooth Mousse (CPP-ACP group) or deionized water (control group) for 3 min and then exposed to in vivo acid attacks by rinsing with 150 ml of a cola drink (4 × 5 min/day). The surface microhardness (SMH) of the specimens was measured and used to calculate the percentage of SMH loss (%SMHl). Erosion effect on enamel was also investigated by scanning electron microscopy (n = 4) at the end of study. The data were statistically analysed using two-way analysis of variance (ANOVA) and Tukey's test at a level of P < 0.05. RESULTS: A significant decrease in %SMHl was observed for the specimens of CPP-ACP group compared to that for the controls (P = 0.007). The specimens positioned posteriorly exhibited a significantly lower %SMHl than those positioned anteriorly (P = 0.033). Samples of CPP-ACP group showed fewer etching patterns than those of the control group. CONCLUSIONS: In this in situ model, application of Tooth Mousse containing CPP-ACP before erosion reduced the %SMHl of human enamel. Enamel located in different positions showed different patterns of erosion. CLINICAL SIGNIFICANCE: Application of Tooth Mousse containing CPP-ACP could be considered as a suitable preventive strategy against enamel erosion. ClinicalTrials.gov Identifier: NCT03426150.


Assuntos
Ácidos , Bebidas Gaseificadas , Caseínas , Erosão Dentária , Ácidos/farmacologia , Caseínas/farmacologia , Estudos Cross-Over , Esmalte Dentário/efeitos dos fármacos , Humanos , Erosão Dentária/prevenção & controle , Remineralização Dentária
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