Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 178
Filter
1.
Sci Rep ; 13(1): 17706, 2023 Oct 17.
Article in English | MEDLINE | ID: mdl-37848454

ABSTRACT

The main purpose of this study is to review the Schenberg resonant antenna transfer function and to recalculate the antenna design strain sensitivity for gravitational waves. We consider the spherical antenna with six transducers in the semi dodecahedral configuration. When coupled to the antenna, the transducer-sphere system will work as a mass-spring system with three masses. The first one is the antenna effective mass for each quadrupole mode, the second one is the mass of the mechanical structure of the transducer first mechanical mode and the third one is the effective mass of the transducer membrane that makes one of the transducer microwave cavity walls. All the calculations are done for the degenerate (all the sphere quadrupole mode frequencies equal) and non-degenerate sphere cases. We have come to the conclusion that the "ultimate" sensitivity of an advanced version of Schenberg antenna (aSchenberg) is around the standard quantum limit (although the parametric transducers used could, in principle, surpass this limit). However, this sensitivity, in the frequency range where Schenberg operates, has already been achieved by the two aLIGOs in the O3 run, therefore, the only reasonable justification for remounting the Schenberg antenna and trying to place it in the sensitivity of the standard quantum limit would be to detect gravitational waves with another physical principle, different from the one used by laser interferometers. This other physical principle would be the absorption of the gravitational wave energy by a resonant mass like Schenberg.

2.
Braz J Biol ; 83: e266108, 2023.
Article in English | MEDLINE | ID: mdl-36790275

ABSTRACT

The effects of onion and its by-products on metabolic changes induced by excessive consumption of a high fat diet have been the focus of many studies. The aim of this study was to systematically review the effects of onion and its by-products antioxidant, anti-inflammatory and anti-obesity in rats exposed to a high-fat diet. Five databases were used: Pubmed, EMBASE, Science Direct, Web of science and Scopus until June 2020 updated December 1, 2022. Research of the articles was carried out by two reviewers, searching and selecting studies after an initial reading of the titles and abstracts. In total, 2,448 papers were found and, after assessing against the inclusion and exclusion criteria, 18 papers were selected for this review. The findings of this review show the beneficial effects of onion and its by-products on inflammatory parameters, obesity, cardiovascular disease, thermogenesis and hepatic alterations generally associated with the consumption of a high-fat diet.


Subject(s)
Antioxidants , Onions , Rats , Animals , Antioxidants/pharmacology , Rodentia , Obesity , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use
3.
Braz. j. biol ; 83: e266108, 2023. ilus, tab
Article in English | VETINDEX | ID: biblio-1417380

ABSTRACT

The effects of onion and its by-products on metabolic changes induced by excessive consumption of a high fat diet have been the focus of many studies. The aim of this study was to systematically review the effects of onion and its by-products antioxidant, anti-inflammatory and anti-obesity in rats exposed to a high-fat diet. Five databases were used: Pubmed, EMBASE, Science Direct, Web of science and Scopus until June 2020 updated December 1, 2022. Research of the articles was carried out by two reviewers, searching and selecting studies after an initial reading of the titles and abstracts. In total, 2,448 papers were found and, after assessing against the inclusion and exclusion criteria, 18 papers were selected for this review. The findings of this review show the beneficial effects of onion and its by-products on inflammatory parameters, obesity, cardiovascular disease, thermogenesis and hepatic alterations generally associated with the consumption of a high-fat diet.


Os efeitos da cebola e seus subprodutos nas alterações metabólicas induzidas pelo consumo excessivo de uma dieta rica em gordura têm sido foco de muitos estudos. O objetivo deste estudo foi revisar sistematicamente os efeitos da cebola e seus subprodutos antioxidantes, anti-inflamatórios e anti-obesidade em ratos expostos a uma dieta hiperlipídica. Foram utilizadas cinco bases de dados: Pubmed, EMBASE, Science Direct, Web of science e Scopus até junho de 2020, atualizado em 01 de dezembro de 2022. A pesquisa dos artigos foi realizada por dois revisores, buscando e selecionando os estudos após leitura inicial dos títulos e resumos. No total, 2.448 artigos foram encontrados e, após avaliação de acordo com os critérios de inclusão e exclusão, 18 artigos foram selecionados para esta revisão. Os achados desta revisão mostram os efeitos benéficos da cebola e seus subprodutos sobre parâmetros inflamatórios, obesidade, doenças cardiovasculares, termogênese e alterações hepáticas geralmente associadas ao consumo de uma dieta hiperlipídica.


Subject(s)
Animals , Rats , Weight Loss/drug effects , Onions/chemistry , Obesity Management/methods , Anti-Inflammatory Agents/analysis , Antioxidants/analysis
4.
Oper Dent ; 47(4): 425-436, 2022 Jul 01.
Article in English | MEDLINE | ID: mdl-35917237

ABSTRACT

OBJECTIVE: This study aimed to evaluate the esthetic efficacy, cytotoxicity, and kinetics of decomposition of hydrogen peroxide (H2O2) present in a commercial bleaching gel with 35% H2O2 (BG35%) chemically activated with manganese oxide (MnO2). METHODS AND MATERIALS: After incorporating 2 mg/mL, 6 mg/mL, and 10 mg/mL of MnO2 into BG35%, the stability of pH and temperature of the products were analyzed. To assess the esthetic efficacy (ΔE and ΔWI), the BG35%s with MnO2 were applied for 45 minutes on enamel/dentin discs (DiE/D). BG35% or no treatment were used as positive (PC) and negative (NC) controls, respectively. To analyze the cell viability (CV) and oxidative stress (OXS), the same bleaching protocols were performed on DiE/D adapted to artificial pulp chambers. The extracts (culture medium + gel components that diffused through the discs) were applied to pulp cells and submitted to H2O2 quantification. BG35% with MnO2 that showed the best results was evaluated relative to kinetic decomposition of H2O2, with consequent generation of free radicals (FR) and hydroxyl radicals (OH•). The data were submitted to the one-way analysis of variance complemented by Tukey post-test (α=0.05). Data on kinetics of H2O2 decomposition were submitted to the Student's-t test (α=0.05). RESULTS: All the BG35%s with MnO2 showed stability of pH and temperature, and the gel with 10 mg/mL of this activator had an esthetic efficacy 31% higher than that of the PC (p<0.05). Reduction in OXS and trans-amelodentinal diffusion of H2O2 occurred when all the BG35%s with MnO2 were used. The addition of 6 and 10 mg/mL of MnO2 to BG35% increased the CV in comparison with PC, confirmed by the cell morphology analysis. An increase in FR and OH• formation was observed when 10 mg/mL of MnO2 was added to BG35%. CONCLUSION: Catalysis of BG35% with MnO2 minimized the trans-amelodentinal diffusion of H2O2 and toxicity of the product to pulp cells. BG35% containing 10 mg/mL of MnO2 potentiated the decomposition of H2O2, enhancing the generation of FR and OH•, as well as the efficacy of the in-office tooth therapy.


Subject(s)
Tooth Bleaching Agents , Tooth Bleaching , Esthetics, Dental , Humans , Hydrogen Peroxide/chemistry , Manganese Compounds , Oxides , Tooth Bleaching/methods
5.
Oper Dent ; 47(1): 87-96, 2022 Jan 01.
Article in English | MEDLINE | ID: mdl-34624102

ABSTRACT

OBJECTIVES: To evaluate the influence of heat application on the degree of conversion (DC) of the 3M Single Bond Universal Adhesive System, as well as its transdentinal cytotoxicity and microtensile bond strength to dentin. METHODS: Experimental groups were established according to the time and temperature of the air jet: G1: 5 seconds-25°C; G2: 10 seconds-25°C; G3: 20 seconds-25°C; G4: 5 seconds-50°C; G5: 10 seconds-50°C; G6: 20 seconds-50°C. In control group (G7), no treatment was performed. The DC was assessed using the Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) technique. For the transdentinal cytotoxicity test, dentin discs fitted in artificial pulp chambers (APC) received the application of the adhesive system and the air jets. For the microtensile bond strength, healthy molars were restored and submitted to the microtensile test after 24 hours and 6 months, respectively. RESULTS: Significant reduction in viability of Mouse Dental Papilla Cell-23 (MDPC-23), which exhibited morphological changes, was observed in all experimental groups compared to control (p<0.05). Although all tested protocols resulted in transdentinal diffusion of 2-hydroxyethyl methacrylate (HEMA), the group G6 presented the highest degree of monomeric conversion and the lowest cytotoxic effect, with higher dentin bond strength values in comparison to group G1 (p<0.05). CONCLUSIONS: Applying an air blast at 50°C for 20 seconds increases the DC and microtensile bond strength of the 3M Single Bond Universal Adhesive System to dentin, as well as reduces the transdentinal cytotoxicity of the material to pulp cells.


Subject(s)
Dental Bonding , Dentin-Bonding Agents , Animals , Composite Resins/chemistry , Dental Cements , Dentin , Dentin-Bonding Agents/chemistry , Materials Testing , Mice , Resin Cements/chemistry , Temperature , Tensile Strength
6.
Oper Dent ; 46(6): E251-E263, 2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34919726

ABSTRACT

OBJECTIVE: To evaluate the mechanical stability and the proteolytic activity of bonds created by a two-step, etch-and-rinse adhesive applied to cross-linked and air-dried etched dentin. METHODS: Flat dentin surfaces were produced in 64 extracted sound human molars. The dentin was etched with 35% phosphoric acid for 15 seconds, and then the teeth were divided into groups according to the cross-linking solution applied on the etched dentin. Group 1: 5% grape seed extract (GSE), Group 2: 5% glutaraldehyde, Group 3: Gluma Desensitizer, or Group 4: deionized water (control). Solutions were applied for 60 seconds, followed by rinse and blot drying. Then, the teeth were separated into two subgroups where the etched dentin was kept moist or air-dried. The adhesive was applied followed by a composite resin buildup. After 24 hours, the teeth were cut into beams (0.81 mm²) that were tested for microtensile strength immediately or after 12 months of aging in a 37°C saliva-like buffer. Additional teeth (n=32) were bonded as described and cut into 0.5-mm-thick slabs. The slabs were prepared for nanoleakage (scanning electron microscopy) and in situ zymography (EnzChek Protease Assay Kit). Bond strength data were submitted to ANOVA and Tukey tests (α =0.05). RESULTS: Significant reduction in immediate bond strength (ca 65%) and increase in proteolytic activity was seen when the etched dentin was air dried without previous cross-linking biomodification. Conversely, bond strengths did not differ from those produced on wet dentin when collagen was cross-linked before air drying, irrespective of the solution applied. For both moist and air-dried etched dentin, collagen cross-linking resulted in mechanically stable bonds and reduced proteolytic activity after 12 months of storage. CONCLUSION: Bonds produced by the application of a two-step, etch-and-rinse adhesive to cross-linked, air-dried, etched dentin were mechanically stable and revealed reduced proteolytic activity after 1 year of aging.


Subject(s)
Dental Bonding , Dentin-Bonding Agents , Collagen , Composite Resins/chemistry , Composite Resins/therapeutic use , Dental Bonding/methods , Dental Cements/therapeutic use , Dentin , Dentin-Bonding Agents/chemistry , Dentin-Bonding Agents/therapeutic use , Materials Testing , Resin Cements/chemistry , Resin Cements/therapeutic use , Tensile Strength
7.
J Dent Res ; 100(10): 1118-1126, 2021 09.
Article in English | MEDLINE | ID: mdl-34315311

ABSTRACT

The development of biomaterials based on the combination of biopolymers with bioactive compounds to develop delivery systems capable of modulating dentin regeneration mediated by resident cells is the goal of current biology-based strategies for regenerative dentistry. In this article, the bioactive potential of a simvastatin (SV)-releasing chitosan-calcium-hydroxide (CH-Ca) scaffold was assessed. After the incorporation of SV into CH-Ca, characterization of the scaffold was performed. Dental pulp cells (DPCs) were seeded onto scaffolds for the assessment of cytocompatibility, and odontoblastic differentiation was evaluated in a microenvironment surrounded by dentin. Thereafter, the cell-free scaffold was adapted to dentin discs positioned in artificial pulp chambers in direct contact with a 3-dimensional (3D) culture of DPCs, and the system was sealed to simulate internal pressure at 20 cm/H2O. In vivo experiments with cell-free scaffolds were performed in rats' calvaria defects. Fourier-transform infrared spectroscopy spectra proved incorporation of Ca and SV into the scaffold structure. Ca and SV were released upon immersion in a neutral environment. Viable DPCs were able to spread and proliferate on the scaffold over 14 d. Odontoblastic differentiation occurred in the DPC/scaffold constructs in contact with dentin, in which SV supplementation promoted odontoblastic marker overexpression and enhanced mineralized matrix deposition. The chemoattractant potential of the CH-Ca scaffold was improved by SV, with numerous viable and dentin sialoprotein-positive cells from the 3D culture being observed on its surface. Cells at 3D culture featured increased gene expression of odontoblastic markers in contact with the SV-enriched CH-Ca scaffold. CH-Ca-SV led to intense mineralization in vivo, presenting mineralization foci inside its structure. In conclusion, the CH-Ca-SV scaffold induces differentiation of DPCs into a highly mineralizing phenotype in the presence of dentin, creating a microenvironment capable of attracting pulp cells to its surface and inducing the overexpression of odontoblastic markers in a cell-homing strategy.


Subject(s)
Chitosan , Animals , Calcium , Cell Differentiation , Dental Pulp , Dentin , Odontoblasts , Rats , Simvastatin/pharmacology
8.
Biomed Pharmacother ; 130: 110592, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32763822

ABSTRACT

OBJECTIVES: The most recent survey conducted by the World Health Organization described Tuberculosis (TB) as one of the top 10 causes of death and the leading cause of death from a single infectious agent. The increasing number of TB-resistant cases has contributed to this scenario. In light of this, new strategies to control and treat the disease are necessary. Our research group has previously described furoxan derivatives as promising scaffolds to be explored as new antitubercular drugs. RESULTS: Two of these furoxan derivatives, (14b) and (14c), demonstrated a high selectivity against Mycobacterium tuberculosis. The compounds (14b) and (14c) were also active against a latent M. tuberculosis strain, with MIC90 values of 6.67 µM and 9.84 µM, respectively; they were also active against monoresistant strains (MIC90 values ranging from 0.61 to 20.42 µM) and clinical MDR strains (MIC90 values ranging from 3.09 to 42.95 µM). Time-kill experiments with compound (14c) showed early bactericidal effects that were superior to those of the first- and second-line anti-tuberculosis drugs currently used in therapy. The safety of compounds (14b) and (14c) was demonstrated by the Ames test because these molecules were not mutagenic under the tested conditions. Finally, we confirmed the safety, and high efficacy of compounds (14b) and (14c), which reduced M. tuberculosis to undetectable levels in a mouse aerosol model of infection. CONCLUSION: Altogether, we have identified two advanced lead compounds, (14b) and (14c), as novel promising candidates for the treatment of TB infection.


Subject(s)
Antitubercular Agents/therapeutic use , Oxadiazoles/therapeutic use , Tuberculosis/drug therapy , Animals , Antitubercular Agents/pharmacology , Antitubercular Agents/toxicity , Bacteria/drug effects , Drug Resistance, Bacterial , Female , Mice , Mice, Inbred BALB C , Microbial Sensitivity Tests , Mutagenicity Tests , Mycobacterium tuberculosis/drug effects , Oxadiazoles/pharmacology , Oxadiazoles/toxicity , Tuberculosis/microbiology
9.
Rev. argent. reumatol ; 30(2): 33-35, jun. 2019. ilus, tab
Article in Spanish | LILACS | ID: biblio-1041883

ABSTRACT

Abatacept es el primer agente biológico aprobado para el tratamiento de la Artritis Reumatoidea (AR) que actúa inhibiendo la co-estimulación de linfocitos T. Si bien se ha reportado su eficacia en psoriasis y artritis psoriásica, existen casos de psoriasis inducida por el fármaco como así también reactivación de las lesiones en pacientes previamente enfermos. Una mujer con antecedentes de AR en tratamiento con Abatacept endovenoso presentó máculas eritemato-escamosas y pruriginosas en toda la superficie corporal, clínica e histológicamente compatibles con psoriasis. La suspensión del tratamiento con Abatacept, ocasionó la desaparición de las lesiones cutáneas. Mas de 4 años después se encuentra en tratamiento con Rituximab sin haber vuelto a presentar compromiso cutáneo.


Abatacept is the first biological agent approved for the treatment of Rheumatoid Arthritis (RA) that acts blocking interaction of T lymphocytes. Although its efficacy in psoriasis and psoriatic arthritis has been reported, there are reports of drug induced psoriasis as well as reactivation of cutaneous lesions. A woman with a history of RA under treatment with Abatacept IV presented erythematous-scaly and pruritic macules on the entire body surface, clinically and histologically compatible with psoriasis. The suspension of treatment with Abatacept caused the disappearance of the cutaneous lesions. More than 4 years later he is in treatment with Rituximab without presenting cutaneous lesions.


Subject(s)
Arthritis, Rheumatoid , Psoriasis , Abatacept
10.
Astrobiology ; 19(9): 1123-1138, 2019 09.
Article in English | MEDLINE | ID: mdl-31084501

ABSTRACT

Glycine is an amino acid that has already been detected in space. It is relevant to estimate its resistance under cosmic radiation. In this way, a sublimate of glycine in α-form on KBr substrate was exposed in the laboratory to a 1.0 keV electron beam. The radiolysis study was performed at 40 K, 80 K, and 300 K sample temperatures. These temperatures were chosen to cover characteristics of the outer space environment. The evolution of glycine compaction and degradation was monitored in real time by infrared spectroscopy (Fourier-transform infrared) by investigation in the spectral ranges of 3500-2100, 1650-1200, and 950-750 cm-1. The compaction cross-section increases as the glycine temperature decreases. The glycine film thickness layer of ∼160 nm was depleted completely after ∼15 min at 300 K under irradiation with ∼1.4 µA beam current on the target, whereas the glycine depletion at 40 K and 80 K occurred after about 4 h under similar conditions. The destruction cross-section at room temperature is found to be (13.8 ± 0.2) × 10-17 cm2, that is, about 20 times higher than the values for glycine depletion at lower temperatures (<80 K). Emerging and vanishing peak absorbance related to OCN- and CO bands was observed in 2230-2100 cm-1 during the radiolysis at 40 K and 80 K. The same new IR bands appear in the range of 1600-1500, 1480-1370, and 1350-1200 cm-1 after total glycine depletion for all temperature configurations. A strong N-H deformation band growing at 1510 cm-1 was observed only at 300 K. Finally, the destruction cross-section associated to tholin decay at room temperature is estimated to be (1.30 ± 0.05) × 10-17 cm2. In addition, a correlation between the formation cross-sections for daughter and granddaughter molecules at 300 K is also obtained from the experimental data.


Subject(s)
Electrons , Glycine/radiation effects , Temperature , Crystallography, X-Ray , Glycine/chemistry , Spectroscopy, Fourier Transform Infrared , Time Factors
11.
J Dev Orig Health Dis ; 9(4): 373-376, 2018 08.
Article in English | MEDLINE | ID: mdl-29559019

ABSTRACT

This study evaluated the effects of diet containing taro flour on hormone levels and the seminiferous tubules morphology of rats. After weaning, the male rats were divided into two groups (n=12 each): control group (CG) treated with control diet and taro group (TG), fed with 25% taro flour for 90 days. Food, caloric intake, mass and body length were evaluated at experiment end. Testis followed the standard histological processing. Immunostaining was performed using an anti-vimentin antibody to identify Sertoli cells. In histomorphometry, total diameter, total area, epithelial height, luminal height and luminal area were analyzed. The testosterone levels were performed using the radioimmunoassay method. Group TG presented (P<0.05): increase in mass, body length, testicular weight, histomorphometric parameters and hormonal levels. Food intake, calorie and Sertoli cells not presented statistical differences. The taro promoted increase in the testicles parameters and hormones.


Subject(s)
Colocasia/chemistry , Flour , Seminiferous Epithelium/cytology , Seminiferous Epithelium/metabolism , Sertoli Cells/metabolism , Testosterone/metabolism , Animals , Male , Rats , Rats, Wistar , Seminiferous Epithelium/drug effects , Sertoli Cells/cytology , Sertoli Cells/drug effects
12.
J Ethnopharmacol ; 213: 21-25, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-29037916

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Pfaffia paniculata is an endemic Brazilian plant traditionally used against fatigue, stress, inflammation and low immune system as well as with proven intestinal anti-inflammatory activity. AIM OF THE STUDY: To evaluate intestinal anti-inflammatory effects of P. paniculata on the mRNA abundance of Hsp70, Heparanase, Mapk1, Mapk3, Mapk6, Mapk9, Muc1, Muc2, Muc3, Muc4, and NF-κB, as well as the mucin content in colonic samples. MATERIAL AND METHODS: Intestinal inflammation was induced by TNBS and rats were divided into groups that received vehicle or 25, 50, 100, or 200mg/kg of P. paniculata extract, p.o., started 2h after inflammation induction and continued daily for 7 days. At the end of the procedure, the animals were killed and their colon samples were obtained for RT-qPCR analysis and mucin histochemical study with PAS/Alcian blue stain. The inflammatory process was confirmed with colon macroscopic analysis and myeloperoxidase (MPO) activity. RESULTS: P. paniculata at 200mg/kg significantly decreased macroscopic damage score, extension of lesion and colonic MPO activity. Besides, P. paniculata at a dose of 25mg/kg was also able to significantly decrease Hsp70, while treatment with 50mg/kg reduced Mapk3 and increased Muc4. At dose of 100mg/kg P. paniculata increased Mapk1, Muc3, Muc4, and decreased Mapk3. Finally, at the 200mg/kg P. paniculata reduced Mapk3. The heparanase, NF-κB, Mapk6, Mapk9, Muc1 and Muc2 mRNA abundances were not altered after P. paniculata treatments. CONCLUSION: Intestinal anti-inflammatory activity of P. paniculata was related to modulation of Mapks and mucin gene expression, as well as mucus secretion in intestinal inflammation.


Subject(s)
Amaranthaceae , Anti-Inflammatory Agents/pharmacology , Gene Expression Regulation/drug effects , Mitogen-Activated Protein Kinases/genetics , Mucins/genetics , Plant Extracts/pharmacology , Animals , Anti-Inflammatory Agents/therapeutic use , Colitis/chemically induced , Colitis/drug therapy , Colitis/genetics , Colitis/pathology , Colon/drug effects , Colon/metabolism , Colon/pathology , Glucuronidase/genetics , Male , Plant Extracts/therapeutic use , Plant Roots , RNA, Messenger/metabolism , Rats, Wistar , Trinitrobenzenesulfonic Acid
13.
Sci Rep ; 7(1): 13982, 2017 10 25.
Article in English | MEDLINE | ID: mdl-29070908

ABSTRACT

In this work, we have constructed and experimentally investigated frustrated arrays of dipoles forming two-dimensional artificial spin ices with different lattice parameters (rectangular arrays with horizontal and vertical lattice spacings denoted by a and b respectively). Arrays with three different aspect ratios γ = a/b = [Formula: see text], [Formula: see text] and [Formula: see text] are studied. Theoretical calculations of low-energy demagnetized configurations for these same parameters are also presented. Experimental data for demagnetized samples confirm most of the theoretical results. However, the highest energy topology (doubly-charged monopoles) does not emerge in our theoretical model, while they are seen in experiments for large enough γ. Our results also insinuate that the string tension connecting two magnetic monopoles in a pair vanishes in rectangular lattices with a critical ratio γ = γ c = [Formula: see text], supporting previous theoretical predictions.

14.
J Dent Res ; 96(13): 1518-1525, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28759300

ABSTRACT

Protease-activated receptors (PARs) are G protein-coupled receptors, which are activated by proteolytical cleavage of the amino-terminus and act as sensors for extracellular proteases. We hypothesized that PAR-1 and PAR-2 can be modulated by inflammatory stimulus in human dental pulp cells. PAR-1 and PAR-2 gene expression in human pulp tissue and MDPC-23 cells were analyzed by quantitative polymerase chain reaction. Monoclonal PAR-1 and PAR-2 antibodies were used to investigate the cellular expression of these receptors using Western blot, flow cytometry, and confocal microscopy in MDPC-23 cells. Immunofluorescence assays of human intact and carious teeth were performed to assess the presence of PAR-1 and PAR-2 in the dentin-pulp complex. The results show for the first time that human odontoblasts and MDPC-23 cells constitutively express PAR-1 and PAR-2. PAR-2 activation increased significantly the messenger RNA expression of matrix metalloproteinase (MMP)-2, MMP-9, MMP-13, and MMP-14 in MDPC-23 cells ( P < 0.05), while the expression of these enzymes decreased significantly in the PAR-1 agonist group ( P < 0.05). The high-performance liquid chromatography and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry analysis showed the presence of MMP-13 activity cleaving PAR-1 at specific, noncanonical site TLDPRS42↓F43LL in human dental pulp tissues. Also, we detected a presence of a trypsin-like activity cleaving PAR-2 at canonical site SKGR20↓S21LIGRL in pulp tissues. Confocal microscopy analysis of human dentin-pulp complex showed intense positive staining of PAR-1 and PAR-2 in the odontoblast processes in dentinal tubules of carious teeth compared to intact ones. The present results support the hypothesis of activation of the upregulated PAR-1 and PAR-2 by endogenous proteases abundant during the inflammatory response in dentin-pulp complex.


Subject(s)
Dental Pulp/cytology , Odontoblasts/enzymology , Receptor, PAR-1/metabolism , Receptor, PAR-2/metabolism , Adult , Blotting, Western , Chromatography, High Pressure Liquid , Flow Cytometry , Humans , Inflammation/metabolism , Matrix Metalloproteinase 13/metabolism , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/metabolism , Microscopy, Confocal , RNA, Messenger/metabolism , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Up-Regulation
15.
Clin Oral Investig ; 21(8): 2509-2520, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28091877

ABSTRACT

OBJECTIVES: This paper aims to assess the whitening effectiveness and toxicity of tooth-bleaching protocols applied to enamel/dentin disks simulating mandibular incisors (ICs) and premolars (PMs). MATERIALS AND METHODS: A 10% hydrogen peroxide (H2O2) gel was applied for 3 × 15, 1 × 15, or 1 × 5 min to enamel/dentin disks simulating mandibular ICs and PMs, and the trans-enamel and trans-dentinal diffusion products were applied to human dental pulp cells (1 h). Professional therapy (35% H2O2-3 × 15 min) was used as positive control, and non-bleached samples were used as negative control. Cell viability and morphology, oxidative stress generation, and odontoblastic marker expression were assessed. The H2O2 diffusion and enamel color change (ΔE) were also analyzed. RESULTS: The 10% H2O2 gel induced significant cell viability reduction only when applied 3 × 15 min, with the intensity of oxidative stress and down-regulation of odontoblastic markers being higher in the IC group. The other experimental bleaching protocols caused slight alterations regarding the cell parameters evaluated, with intensity being related to enamel/dentin thickness. These effects were also correlated with higher H2O2 diffusion in the IC group. ΔE values similar as positive control were found for the 10% 3 × 15 and 1 × 15 protocols on IC group, after 4 and 6 sessions. CONCLUSION: Application of a 10% H2O2 bleaching gel for 15 or 45 min to thin dental substrate significantly minimizes cell toxicity in comparison with highly concentrated gels associated with similar esthetic outcomes by increasing the number of bleaching sessions. CLINICAL RELEVANCE: Bleaching gels with 10% H2O2 applied in small teeth for short periods may be an interesting alternative to obtain whitening effectiveness without causing toxicity to pulp cells, which may be able to reduce the tooth hypersensitivity claimed by patients.


Subject(s)
Dental Enamel/drug effects , Esthetics, Dental , Hydrogen Peroxide/pharmacology , Hydrogen Peroxide/toxicity , Tooth Bleaching Agents/pharmacology , Tooth Bleaching Agents/toxicity , Tooth Bleaching/methods , Alkaline Phosphatase/analysis , Biomarkers/analysis , Cell Survival/drug effects , Cells, Cultured , Dental Pulp/cytology , Gels , Humans , In Vitro Techniques , Odontoblasts/drug effects , Oxidative Stress , Time Factors
16.
Int Endod J ; 50(6): 549-559, 2017 Jun.
Article in English | MEDLINE | ID: mdl-27238557

ABSTRACT

AIM: To evaluate the effects of infrared light-emitting diode (LED) irradiation on stem cells from human exfoliated deciduous teeth (SHEDs). METHODOLOGY: Exfoliated primary teeth were obtained (n = 3), and SHEDs obtained from the teeth were seeded on the pulpal surface of 0.2-mm-thick dentine discs produced from permanent molars. The cells were incubated for 24 h by placing the discs in plain Dulbecco's modified Eagle's medium (DMEM). The DMEM was then replaced with new culture medium formulated for odontoblast differentiation. After 12 h in the second medium, SHEDs were irradiated through the dentine discs using an infrared LED (850 nm) with a power density of 80 mW cm-2 . Energy doses (EDs) delivered to the occlusal surface of the dentine discs were 0 (control), 2 and 4 J cm-2 (n = 6). Subsequent tests were performed 72 h after irradiation. These tests included cell viability (MTT), alkaline phosphatase activity (ALP), total protein production (TP), scanning electron microscopy (SEM), as well as gene expression for ALP, Col I, DSPP and DMP-1. Data were analysed using Kruskal-Wallis and Mann-Whitney t-tests (α = 0.05). RESULTS: Both EDs (2 and 4 J cm-2 ) significantly increased cell viability and ALP activity. For TP, ALP and Col I gene expression, only the 4 J cm-2 group had significantly higher values compared to the control group. Cell morphology was not affected by irradiation. CONCLUSION: Infrared LED irradiation was capable of biostimulating SHEDs through a 0.2 mm thickness of dentine, especially at the 4 J cm-2 level.


Subject(s)
Stem Cells/cytology , Tooth Exfoliation/metabolism , Tooth, Deciduous/cytology , Cell Survival , Dentin/radiation effects , Humans , Light , Stem Cells/radiation effects , Tooth, Deciduous/radiation effects
17.
J Photochem Photobiol B ; 159: 205-10, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27085052

ABSTRACT

Previous studies have demonstrated that high biostimulation takes place when cells under stress are subjected to phototherapy by laser or light-emitting-diode (LED) devices. Several studies selected nutritional deprivation by reducing the concentration of fetal bovine serum (FBS) in the culture medium or the exposure of cultured cells to lipopolysaccharide (LPS) as an in vitro cellular stress condition. However, there are no data certifying that these stimuli cause stressful conditions for cultured cells. This investigation assessed the induction of cellular stress by decreasing the concentration of FBS or adding LPS to culture medium. Odontoblast-like cells (MDPC-23) were cultured in complete culture medium (DMEM) containing 10% FBS. After a 12-hour incubation period, the DMEM was replaced by fresh medium containing 10% FBS (control), low concentrations of FBS (0, 0.2, 0.5, 2, or 5%) or LPS from Escherichia coli (10µg/ml). After an additional 12-hour incubation, cell viability, total cell-counting, total protein production, and gene expression of heat shock protein 70 (HSP70) were assessed. Data were statistically analyzed by ANOVA complemented by the Tukey test, with 5% considered significant. Cell viability was negatively affected only for 0% FBS, while reduced viable cell numbers and total protein production were detected for FBS concentrations lower than 2%. Higher HSP70 gene expression was also observed for FBS concentrations lower than 2% and for cells exposed to LPS. The nutritional deprivation model with culture medium lower than 2% of FBS can be safely used to induce cellular stress for in vitro photobiomodulation studies.


Subject(s)
Lipopolysaccharides/pharmacology , Nutritional Status , Animals , Cell Line, Transformed , Culture Media , HSP70 Heat-Shock Proteins/metabolism
18.
Oral Dis ; 22(5): 415-22, 2016 Jul.
Article in English | MEDLINE | ID: mdl-26914185

ABSTRACT

This study evaluated the photoinactivation of Candida albicans in a murine model of oral candidiasis using chloro-aluminum phthalocyanine (ClAlP) encapsulated in cationic nanoemulsions (NE) and chloro-aluminum phthalocyanine (ClAlP) diluted in DMSO (DMSO) as photosensitizer (PS). Seventy-five 6-week-old female Swiss mice were immunosuppressed and inoculated with C. albicans to induce oral candidiasis. PDT was performed on the tongue by the application of the photosensitizers and LED light (100 J cm(-2) -660 nm). Twenty-four hours and 7 days after treatments, microbiological evaluation was carried out by recovering C. albicans from the tongue of animals (CFU ml(-1) ). Then, mice were sacrificed and the tongues were surgically removed for histological and biomolecular analysis of pro- and anti-inflammatory cytokines. Data were analyzed by ANOVA followed by Tukey's post hoc test. ClAlP-NE-mediated PDT reduced 2.26 log10 of C. albicans recovered from the tongue when compared with the control group (P-L-) (P < 0.05). PDT did not promote adverse effects on the tongue tissue. Seven days after treatment, all animals were completely healthy. In summary, PDT mediated by chloro-aluminum phthalocyanine entrapped in cationic nanoemulsions was effective in reducing C. albicans recovered from the oral lesions of immunocompromised mice.


Subject(s)
Candida albicans/drug effects , Candida albicans/radiation effects , Candidiasis, Oral/drug therapy , Indoles/pharmacology , Organometallic Compounds/pharmacology , Photochemotherapy/methods , Animals , Candida albicans/isolation & purification , Candidiasis, Oral/microbiology , Cytokines/analysis , Cytokines/genetics , Disease Models, Animal , Female , Mice , Photosensitizing Agents/pharmacology , Random Allocation , Tetracycline/pharmacology , Tongue/drug effects , Tongue/microbiology , Tongue/radiation effects
19.
J Dev Orig Health Dis ; 7(3): 314-319, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26639737

ABSTRACT

Obesity and osteoporosis may have their origins in early postnatal life. This study was designed to evaluate whether flaxseed flour use during lactation period bears effect on body adiposity and skeletal structure of male rat pups at weaning. At birth, male Wistar rats were randomly assigned to control and experimental (FF) groups, whose dams were treated with control or flaxseed flour diet, respectively, during lactation. At 21 days of age, pups were weaned to assess body mass, length and composition by dual-energy X-ray absorptiometry. The animals were then sacrificed to carry out analysis of serum profile, intra-abdominal adipocyte morphology and femur characteristics. Differences were considered significant when P<0.05. The FF group displayed the following characteristics (P<0.05): higher body mass, length, bone mineral content, bone area and concentrations of osteoprotegerin, osteocalcin and high-density lipoprotein cholesterol; higher levels of stearic, α-linolenic, eicosapentaenoic and docosapentaenoic acids and lower levels of arachidonic acid and cholesterol; smaller adipocyte area; and higher mass, epiphysis distance, diaphysis width, maximal load, break load, resilience and stiffness of femur. Flaxseed flour intake during lactation period promoted adipocyte hypertrophy down-regulation and contributed to pup bone quality at weaning.

20.
Int Endod J ; 49(1): 26-36, 2016 Jan.
Article in English | MEDLINE | ID: mdl-25557717

ABSTRACT

AIM: To assess the initial cytotoxicity and the late phenotype marker expression of odontoblast-like cells (MDPC-23) subjected to less aggressive in-office bleaching therapies. METHODOLOGY: A 17.5% hydrogen peroxide (H2O2) gel was applied for 45, 15 or 5 min to enamel/dentine discs adapted to trans-wells positioned over cultured MDPC-23 cells. No treatment was performed on the negative control. Immediately after bleaching, the cell viability, gene expression of inflammatory mediators and quantification of H2O2 diffusion were evaluated. The ALP activity, DSPP and DMP-1 gene expression and mineralized nodule deposition (MND) were assessed at 7, 14 or 21 days post-bleaching and analysed statistically with Mann-Whitney U-tests (α = 5%). RESULTS: H2O2 diffusion, proportional to treatment time, was observed in all bleached groups. Reductions of approximately 31%, 21% and 13% in cell viability were observed for the 45-, 15- and 5-min groups, respectively. This reduction was significant (P < 0.05) for the 45- and 15-min groups, which also presented significant (P < 0.05) over-expression of inflammatory mediators. The 45-min group was associated with significant (P < 0.05) reductions in DMP-1/DSPP expression at all periods, relative to control. The ALP activity and MND were reduced only in initial periods. The 15-min group had less intense reduction of all markers, with no difference to control at 21 days. CONCLUSIONS: The 17.5% H2O2 applied to tooth specimens for 5 min caused no alteration in the odontoblast-like cells. When this gel was applied for 45 or 15 min, a slight cytotoxicity, associated with alterations in phenotypic markers, was observed. However, cells were able to recover their functions up to 21 days post-bleaching.


Subject(s)
Hydrogen Peroxide/toxicity , Odontoblasts/drug effects , Tooth Bleaching Agents/toxicity , Alkaline Phosphatase/metabolism , Cell Survival , Cells, Cultured , Gels , Inflammation Mediators/metabolism , Phenotype , Reproducibility of Results
SELECTION OF CITATIONS
SEARCH DETAIL