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1.
J Prosthet Dent ; 132(3): 626.e1-626.e8, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39013680

RESUMO

STATEMENT OF PROBLEM: While repurposing waste materials into zirconia blocks presents a promising avenue, uncertainty remains regarding whether the bonding properties of recycled zirconia align with those of commercially available zirconia. PURPOSE: The purpose of this in vitro study was to evaluate the bonding affinity and durability of composite resin to recycled zirconia. MATERIAL AND METHODS: A series of processing steps were performed with recycled zirconia residuals (Lava Plus; 3M Oral Care), including pulverization, sieving, heating, compaction, isostatic pressing, and presintering. The presintered blocks of recycled zirconia (Group R) and commercially available zirconia (Group C) were sectioned and sintered to create test specimens (10×10×1.5 mm). After polishing and airborne-particle abrasion, specimens within each group were bonded to composite resin cylinders using a resin cement (Multilink Speed; Ivoclar AG). The specimens were then divided into 3 subgroups for shear bond strength (SBS) testing: no further treatment, 10 000 thermocycles, and 30 000 thermocycles (n=10). X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), surface roughness, and contact angle were used to analyze the surface physicochemical differences between Groups C and R. Data were analyzed with 2-way ANOVA followed by the Tukey post hoc test for SBS values, Pearson chi-squared test for failure modes, and independent t test for grain size, surface roughness, and wettability (α=.05). RESULTS: No significant difference was found in the SBS values between Group R and Group C (P=.403), while thermocycling significantly affected the SBS values (P<.05). Group R showed significantly greater Ra, Rz, and Rq values (P<.05) than did Group C. SEM analysis revealed that Group R exhibited more prominent grooves than Group C, while the XRD and EDS patterns exhibited similarities in both the crystalline phase and elemental composition. No significant difference was observed in the water contact angle between the 2 groups (P=.196). CONCLUSIONS: The bonding protocol established for commercially available zirconia was comparable with that of recycled zirconia, but both decreased after thermocycling. The recycling process did not affect the crystalline phase or elemental composition of the zirconia, but it induced alterations in the surface roughness.


Assuntos
Resinas Compostas , Colagem Dentária , Teste de Materiais , Microscopia Eletrônica de Varredura , Cimentos de Resina , Resistência ao Cisalhamento , Propriedades de Superfície , Zircônio , Zircônio/química , Resinas Compostas/química , Colagem Dentária/métodos , Cimentos de Resina/química , Reciclagem , Materiais Dentários/química , Difração de Raios X , Análise do Estresse Dentário , Técnicas In Vitro , Espectrometria por Raios X , Humanos
2.
J Dent ; 147: 105109, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38849053

RESUMO

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.


Assuntos
Esmalte Dentário , Dentina , Vidro , Dureza , Microscopia Eletrônica de Varredura , Fluoreto de Sódio , Espectrometria por Raios X , Erosão Dentária , Dente Decíduo , Erosão Dentária/prevenção & controle , Humanos , Vidro/química , Fluoreto de Sódio/uso terapêutico , Propriedades de Superfície , Cerâmica/química , Desmineralização do Dente/prevenção & controle , Teste de Materiais
3.
Molecules ; 27(13)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35807238

RESUMO

The antitumor effects of Coix lacryma-jobi L. var. ma-yuen Stapf. (adlay seed) ethanolic extract have been increasingly shown. This study aimed to investigate the beneficial effects of both the fractions and subfractions of adlay seed ethanolic extract on the human breast (MCF-7) and cervical (HeLa) cancer cell lines, as well as exploring their possible mechanisms of action. The ethanolic extracts were obtained from different parts of adlay seed, including AHE (adlay hull extract), ATE (adlay testa extract), ABE (adlay bran extract) and PAE (polished adlay extract). The results of a 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl- tetrazolium bromide (MTT) assay showed that AHE-Ea and ATE-Ea showed significant growth inhibitory effects in a dose-dependent manner. The results also showed that the AHE-Ea-K, AHE-Ea-L, ATE-Ea-E and ATE-Ea-F subfractions inhibited cell proliferation, induced cell cycle arrest in the G0/G1 phase and decreased CDK4/Cyclin D1 protein expression. Finally, the extract activated caspase-3 activity and PARP protein expression, which induced MCF-7 and HeLa cell apoptosis. We then used liquid chromatography-mass spectrometry (LC/MS) to identify the potential active components., Quercetin showed an anticancer capacity. In conclusion, the AHE-Ea-K, AHE-Ea-L, ATE-Ea-E and ATE-Ea-F subfractions showed antitumor effects through the inhibition of MCF-7 and HeLa cell line viability, as well as inducing apoptosis and cell cycle arrest.


Assuntos
Coix , Neoplasias do Colo do Útero , Apoptose , Pontos de Checagem do Ciclo Celular , Coix/química , Etanol/farmacologia , Feminino , Células HeLa , Humanos , Extratos Vegetais/química , Sementes/química , Neoplasias do Colo do Útero/tratamento farmacológico
4.
Cancer Manag Res ; 11: 2129-2138, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30936745

RESUMO

BACKGROUND: Non-small-cell lung cancer (NSCLC) is a global public health problem, and brain is a common metastatic site in advanced NSCLC. Currently, whole-brain radiotherapy (WBRT) remains a major treatment for brain metastases, while EGFR-tyrosine kinase inhibitor (TKI) is the standard treatment for advanced NSCLC harboring EGFR mutations, which is also effective for brain metastases. However, whether EGFR-TKIs plus radiotherapy is superior to EGFR-TKIs alone for the treatment of advanced EGFR-mutant NSCLS with brain metastases remains controversial. This study aimed to compare the efficacy of concurrent EGFR-TKIs and WBRT vs EGFR-TKI alone in a retrospective cohort of advanced EGFR-mutant NSCLS with brain metastases. PATIENTS AND METHODS: The medical records of 104 treatment-naïve, advanced EGFR-mutant NSCLC patients with brain metastases were retrospectively reviewed, and there were 56 patients undergoing concurrent EGFR-TKI and WBRT, and 48 patients given EGFR-TKI alone, including 20 cases with salvage WBRT upon brain metastasis progression. The survival prognosis was compared between the two cohorts. RESULTS: The baseline clinicopathologic factors were balanced between the two cohorts. After a median follow-up of 23 months, 35.6% of the study subjects survived. Concurrent EGFR-TKI and WBRT significantly improved the median intracranial PFS (iPFS) compared with EGFR-TKI alone (17.7 vs 11.0 months, P=0.015); however, no significant difference was seen in median overall survival between the two cohorts (28.1 vs 24.0 months, P=0.756). In addition, the median iPFS was found to significantly vary in the number of brain metastases (≤3 vs>3 metastases: 18.0 vs 12.5 months, P=0.044). Subgroup analysis showed that concurrent EGFR-TKI and WBRT improved median iPFS compared with EGFR-TKI alone in patients with more than three brain metastases (P=0.001); however, no significant difference was observed between the two regimens in patients with three or less brain metastases (P=0.526). CONCLUSION: Our data demonstrate that concurrent EGFR-TKI and WBRT achieves longer iPFS than EGFR-TKI alone in advanced EGFR-mutant NSCLC with brain metastases. In advanced EGFR-mutant NSCLC with three or less brain metastases, EGFR-TKI alone may be an option as a first-line therapy.

5.
Oncotarget ; 8(2): 3412-3421, 2017 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-27926500

RESUMO

OBJECTIVE: This study aimed to examine the association of clinical prognostic factors with epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) efficacy in advanced non-small-cell lung cancer (NSCLC) patients. METHODS: The demographic and clinical characteristics of 94 patients with stage IV NSCLC were retrospectively reviewed, and the association between clinical factors and EGFR-TKIs efficacy was evaluated. RESULTS: Of the 94 stage IV NSCLC patients enrolled in this study, a 74.5% objective response rate (ORR) and 97.9% disease control rate (DCR) were observed for EGFR-TKIs treatment, and a higher ORR was seen in patients with 0 and 1 ECOG scores than those with 2 or greater scores (P = 0.049). The subjects had a median PFS of 11 months and a median OS of 31 months after EGFR-TKIs treatment. ECOG score and timing of targeted therapy were factors affecting PFS, and ECOG score, smoking status and brain metastasis were factors affecting OS. In addition, ECOG score was an independent prognostic factor for PFS in stage IV NSCLC patients, and the patients with EGFR 19del mutation had a longer PFS than those with exon 21 L855R mutation (P = 0.003), while ECOG score and brain metastasis were independent prognostic factors for OS. CONCLUSIONS: The results of this study demonstrate that EGFR-TKI therapy results in survival benefits for EGFR-mutant advanced NSCLC patients, regardless of gender, smoking history, pathologic type, type of EGFR mutations, brain metastasis and timing of targeted therapy. ECOG score is an independent prognostic factor for PFS, and ECOG score and brain metastasis are independent prognostic factors for OS in advanced NSCLC patients.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Receptores ErbB/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Inibidores de Proteínas Quinases/uso terapêutico , Adulto , Idoso , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Mutação , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Inibidores de Proteínas Quinases/farmacologia , Estudos Retrospectivos , Resultado do Tratamento
6.
J Agric Food Chem ; 59(4): 1185-94, 2011 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-21284381

RESUMO

Two new lactams, coixspirolactam D (1) and coixspirolactam E (2), and a new spiroenone, coixspiroenone (3), together with seven known compounds, coixspirolactam A (4), coixspirolactam B (5), coixspirolactam C (6), coixlactam (7), coixol (8), ethyl dioxindole-3-acetate (9), and isoindol-1-one (10), and two neolignans, zhepiresionol (11) and ficusal (12), were isolated from the bioactive subfraction of adlay bran ethanolic extract (ABE). Compounds 9 and 10 are the first isolates from natural resources. The structures of new compounds were identified by spectroscopic methods, including infrared (IR) spectrum, 1D and 2D nuclear magnetic resonance (NMR), and mass spectrum (MS). All of the isolated compounds were tested for antiproliferative effects on MCF-7, MDA-MB-231, and T-47D cells. Results showed that compounds 1, 3, 4, 6, and 7 at 50 µM significantly inhibited MCF-7 cell proliferation by 30.2, 19.2, 21.0, 13.5, and 32.4%, respectively; compounds 2, 4, and 7 significantly inhibited T-47D cells at 50 µM by 20.7, 24.8, and 28.9%; and compounds 1, 2, and 12 significantly inhibited MDA-MB-231 cells at 50 µM by 47.4, 25.3, and 69.3%, respectively. In conclusion, ABE has antiproliferative activities, and this effect is partially related to the presence of lactams and spiroenone.


Assuntos
Divisão Celular/efeitos dos fármacos , Coix/química , Lactamas/farmacologia , Compostos de Espiro/farmacologia , Antineoplásicos Fitogênicos , Neoplasias da Mama , Linhagem Celular Tumoral , Humanos , Lactamas/química , Lactamas/isolamento & purificação , Sementes/química , Compostos de Espiro/química , Compostos de Espiro/isolamento & purificação
7.
Beijing Da Xue Xue Bao Yi Xue Ban ; 37(3): 287-91, 2005 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-15968322

RESUMO

OBJECTIVE: To investigate the clinical value of dual-phase imaging of 18F-fluoro-2-deoxy-D-glucose (18F-FDG) using single photon emission computed tomography with coincidence detection (SPECT with coincidence) for differentiating benign and malignant lesions. METHODS: Thirty patients with unknown lesions from June 2003 to March 2004 in our hospital were enrolled in this study. All patients underwent dual-phase imaging of 18F-FDG SPECT with coincidence. The early images were obtained 60 min post injection. And the patients were divided into 2 groups, one receiving delayed scans at 210 min after 18F-FDG injection and the other at 270 min. Lesion status was determined by pathologic findings or by clinical follow-up. RESULTS: Forty-eight lesions (30 malignant and 18 benign lesions verified by pathologic findings or clinical follow-up) of 30 patients were detected by dual-phase imaging, in which there were 29 true positive results, 15 true negative, 3 false positive and 1 false negative. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of dual-phase imaging were 96.7%, 83.3%, 91.6%, 90.6%, and 93.8%, respectively. Those of early imaging and CT were 93.3%, 72.2%, 85.4%, 84.8%, 86.7% and 76.9%, 57.1%, 70.0%, 76.9%, 57.1%, respectively. The T/NT of all malignant lesions (except 1 false negative case) in delayed imaging were significantly increased (t=-3.071, P<0.01). However, there were no statistical differences in the T/NT of benign lesions (t=0.398, P=0.695) between early and delayed imagings. CONCLUSION: Dual-phase imaging of FDG SPECT with coincidence provides benefit for differentiating benign and malignant lesions.


Assuntos
Radioisótopos de Flúor , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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