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1.
Int Endod J ; 52(4): 424-438, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30244498

RESUMO

AIM: To evaluate the potential biostimulatory effects of grape seed extract (GSE) on a primary culture of human pulp cells. METHODOLOGY: Human molars were used to obtain the primary pulp cell culture and 0.5-mm dentine discs. For GSE direct exposure, dose-response (0.0065-6.5%) and time response (1-60 min of contact) were examined. For transdentinal exposure, 0.65% of GSE was tested for 24 h. Cellular metabolism, nitric oxide and collagen production, and cell morphology alterations were assessed at periods of 24 and 72 h. After cell differentiation and direct exposure to GSE, the total protein production (TP), alkaline phosphatase activity (ALP) and formation of mineralization nodules (MN) were assessed. The results were analysed by parametric tests or non-parametric tests (α = 0.05). RESULTS: The lower concentration of GSE tested (0.0065%) was associated with an increase in cellular metabolism, a reduction in the production of nitric oxide and an increase in extracellular matrix synthesis (collagen). Distinct behaviours were observed for the different concentrations, without a reduction of cellular metabolism >10% compared with the control, either when applied directly or transdentinally. SEM revealed no significant change in cell morphology, except for the positive control (H2 O2 ). There was no difference in TP, ALP or MN between the control group and the group exposed to GSE. CONCLUSIONS: Treatment with grape seed extract, even at the highest concentration and longest period, caused neither direct nor transdentinal cytotoxic effects on human pulp cells. Grape seed extract components may play a biostimulatory role and protect dental pulp cells when in direct contact.


Assuntos
Extrato de Sementes de Uva , Proantocianidinas , Diferenciação Celular , Polpa Dentária , Dentina , Humanos
2.
Int Endod J ; 49(6): 551-60, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26059801

RESUMO

AIM: To evaluate the transdentinal cytotoxicity of resin-based luting cements (RBLCs), with no HEMA in their composition, to odontoblast-like cells. METHODOLOGY: Human dentine discs 0.3 mm thick were adapted to artificial pulp chambers (APCs) and placed in wells of 24-well plates containing 1 mL of culture medium (DMEM). Two categories of HEMA-free RBLCs were evaluated: group 1, self-adhesive Rely X Unicem (RU; 3M ESPE), applied directly to the dentine substrate; and group 2, Rely X ARC (RARC; 3M ESPE), applied to dentine previously acid-etched and treated with a bonding agent. In group 3 (control), considered as representing 100% cell metabolic activity, no treatment was performed on dentine. The APC/disc sets were incubated for 24 h or 7 days at 37 °C and 5% CO2 . Then, the extracts (DMEM + dental materials components that diffused through dentine) were applied to cultured odontoblast-like MDPC-23 cells for 24 h. After that, the cell viability (MTT assay), cell morphology (SEM), total protein production (TP) and alkaline phosphatase (ALP) activity were assessed. Data from MTT assay and TP production were analysed by Kruskal-Wallis and Mann-Whitney tests (α = 5%). Data from ALP activity were analysed by one-way anova and Tukey's test (α = 5%). RESULTS: In group 1, a slight reduction in cell viability (11.6% and 16.8% for 24-h and 7-day periods, respectively) and ALP activity (13.5% and 17.9% for 24-h and 7-day periods, respectively) was observed, with no significant difference from group 3 (control) (P > 0.05). In group 2, a significant reduction in cell viability, TP production and ALP activity compared with group 3 (control) occurred (P < 0.05), regardless of incubation time. Alteration in MDPC-23 cell morphology was observed only in group 2. CONCLUSIONS: HEMA-free Rely X ARC cement caused greater toxicity to odontoblast-like MDPC-23 cells than did Rely X Unicem cement when both resin-based luting materials were applied to dentine as recommended by the manufacturer.


Assuntos
Cimentos Dentários/uso terapêutico , Dentina/metabolismo , Resinas Sintéticas/uso terapêutico , Fosfatase Alcalina/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cimentos Dentários/efeitos adversos , Dentina/efeitos dos fármacos , Humanos , Odontoblastos/efeitos dos fármacos , Proteínas/metabolismo , Resinas Sintéticas/administração & dosagem
3.
Parasite Immunol ; 36(7): 303-12, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24749785

RESUMO

Schistosoma mansoni is a blood fluke parasite responsible for schistosomiasis. The best long-term strategy to control schistosomiasis is through immunization combined with drug treatment. In this study, we cloned, expressed and purified SmTSP-2 fused to the N- and C-terminal halves of Sm29 and tested these chimeras as vaccine candidates using an adjuvant approved to be used in humans. The results demonstrated that vaccination with SmTSP-2 fused to N- or C-terminus of Sm29-induced reduction in worm burden and liver pathology when compared to control animals. Additionally, we detected high levels of mouse-specific IgG, IgG1 and IgG2a against both chimeras and significant amounts of IFN-γ and TNF-α and no IL-4. Finally, studies with sera from patients resistant to infection and living in schistosomiasis endemic areas revealed high levels of specific IgG to both chimeras when compared to healthy individuals. In conclusion, SmTSP-2/Sm29 chimeras tested here induced partial protection against infection and might be a potential vaccine candidate.


Assuntos
Antígenos de Bactérias/imunologia , Antígenos de Helmintos/imunologia , Proteínas de Bactérias/imunologia , Proteínas de Helminto/imunologia , Glicoproteínas de Membrana/imunologia , Schistosoma mansoni , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/prevenção & controle , Tetraspaninas/imunologia , Vacinas/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Bactérias/administração & dosagem , Antígenos de Helmintos/administração & dosagem , Proteínas de Bactérias/administração & dosagem , Ilhas de CpG , Citocinas/sangue , Feminino , Proteínas de Helminto/administração & dosagem , Humanos , Imunoglobulina G/sangue , Fígado/patologia , Glicoproteínas de Membrana/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Oligodesoxirribonucleotídeos/administração & dosagem , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia , Tetraspaninas/administração & dosagem , Vacinas/administração & dosagem
4.
Int Endod J ; 44(2): 116-25, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21083572

RESUMO

AIM: To evaluate the transenamel and transdentinal cytotoxicity of bleaching gels based on carbamide peroxide (CP) on odontoblast-like cells after different contact times of the products with enamel. METHODOLOGY: Enamel/dentine discs were obtained from bovine incisors and placed in artificial pulp chambers. Bleaching gels containing 10% or 16% CP were applied for 8 h day(-1) on the enamel side of the discs during periods of 1, 7 or 14 days. Deionized water and artificial saliva served as controls. The extracts (culture medium plus bleaching gel products that diffused through the discs) were collected and applied on previously cultured MDPC-23 cells for 1 h. Cell metabolism was evaluated by the MTT assay, and the data were analysed statistically by one-way anova and Tukey's test (α=0.05). Cell morphology was analysed by SEM. RESULTS: There was no significant difference (P>0.05) between the controls and the groups bleached with 10% CP gel. In the groups bleached with 16% CP gel, however, cell metabolism decreased significantly (P<0.05) by 40.32%, 30.16% and 26.61% at 1, 7 and 14 days, respectively. There was no significant difference (P>0.05) between 1, 7 or 14 applications of the gels for either of the CP concentrations. CONCLUSION: Regardless of the number of applications on an enamel surface, the 10% CP bleaching gel did not cause transenamel and transdentinal cytotoxicity to the MDPC-23 cell cultures. However, diffusion of products from the 16% CP gel through enamel and dentine and cytopathic effects to the pulp cells occurred even after a single application of this product on enamel.


Assuntos
Esmalte Dentário/efeitos dos fármacos , Dentina/efeitos dos fármacos , Odontoblastos/efeitos dos fármacos , Peróxidos/toxicidade , Clareadores Dentários/toxicidade , Ureia/análogos & derivados , Análise de Variância , Animais , Peróxido de Carbamida , Bovinos , Células Cultivadas , Permeabilidade do Esmalte Dentário/efeitos dos fármacos , Relação Dose-Resposta a Droga , Géis , Peróxidos/farmacocinética , Estatísticas não Paramétricas , Fatores de Tempo , Clareadores Dentários/farmacocinética , Ureia/farmacocinética , Ureia/toxicidade
5.
Int Endod J ; 43(7): 572-80, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20456515

RESUMO

AIM: To evaluate in vivo the microscopic pulpal response in sound human premolar teeth subjected to vital tooth bleaching with a 38% hydrogen peroxide (H(2)O(2)) bleaching gel (Opalescence X-tra Boost) catalysed or not by a halogen light source. METHODOLOGY: Twelve pairs of sound maxillary and/or mandibular premolar teeth from 12 to 18-year-old patients were selected and randomly assigned to the following experimental (n = 10) and control (n = 4) groups: group 1: bleaching gel + halogen light; group 2: bleaching gel; group 3: no treatment (control). The teeth were extracted 2-15 days after bleaching and were subjected to routine laboratory processing for histological analysis of the pulpal response under light microscopy. RESULTS: In almost all specimens of the experimental groups, the pulp tissue exhibited histological characteristics of normality. Only one specimen in each group exhibited some dilated and congested blood vessels among a discrete number of mononuclear inflammatory cells in the peripheral pulp region related to the buccal surface of the tooth. These specimens had a slight disruption to the odontoblastic layer, which characterized discrete tissue disorganization. Some deposition of reactionary dentine occurred in only one specimen of group 2. CONCLUSIONS: Professionally applied vital tooth bleaching with a 38% H(2)O(2) gel with or without activation by a halogen light source did not cause damage to the pulp tissue of sound human premolar teeth.


Assuntos
Polpa Dentária/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Oxidantes/farmacologia , Clareamento Dental/métodos , Adolescente , Dente Pré-Molar , Criança , Lâmpadas de Polimerização Dentária , Feminino , Humanos , Masculino
6.
Int Endod J ; 42(6): 516-24, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19460001

RESUMO

AIM: To evaluate the trans-enamel and trans-dentinal cytotoxic effects of a 35% H(2)O(2) bleaching gel on an odontoblast-like cell lines (MDPC-23) after consecutive applications. METHODOLOGY: Fifteen enamel/dentine discs were obtained from bovine central incisor teeth and placed individually in artificial pulp chambers. Three groups (n = 5 discs) were formed according to the following enamel treatments: G1: 35% H(2)O(2) bleaching gel (15 min); G2: 35% H(2)O(2) bleaching gel (15 min) + halogen light (20 s); G3: control (no treatment). After repeating the treatments three consecutive times, the extracts (culture medium + gel components that had diffused through enamel/dentine discs) in contact with the dentine were collected and applied to previously cultured MDPC-23 cells (50 000 cells cm(-2)) for 24 h. Cell metabolism was evaluated by the MTT assay and data were analysed statistically (alpha = 5%; Kruskal-Wallis and Mann-Whitney U-test). Cell morphology was analysed by scanning electron microscopy. RESULTS: Cell metabolism decreased by 92.03% and 82.47% in G1 and G2 respectively. G1 and G2 differed significantly (P < 0.05) from G3. Regardless of halogen light activation, the application of the bleaching gel on the cultured odontoblast-like cells caused significantly more severe cytotoxic effects than those observed in the nontreated control group. In addition, significant morphological cell alterations were observed in G1 and G2. CONCLUSION: After three consecutive applications of a 35% H(2)O(2) bleaching agent, the diffusion of the gel components through enamel and dentine caused severe toxic effects to cultured pulp cells.


Assuntos
Permeabilidade do Esmalte Dentário/efeitos dos fármacos , Permeabilidade da Dentina/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Odontoblastos/efeitos dos fármacos , Clareamento Dental/efeitos adversos , Administração Tópica , Animais , Bovinos , Células Cultivadas , Esmalte Dentário/efeitos dos fármacos , Dentina/efeitos dos fármacos , Esquema de Medicação , Peróxido de Hidrogênio/administração & dosagem , Luz , Odontoblastos/efeitos da radiação , Oxidantes/administração & dosagem , Oxidantes/toxicidade , Estatísticas não Paramétricas , Clareamento Dental/métodos
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