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1.
Sci Rep ; 13(1): 17706, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848454

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-36790275

RESUMO

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.


Assuntos
Antioxidantes , Cebolas , Ratos , Animais , Antioxidantes/farmacologia , Roedores , Obesidade , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico
3.
Oper Dent ; 47(4): 425-436, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35917237

RESUMO

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.


Assuntos
Clareadores Dentários , Clareamento Dental , Estética Dentária , Humanos , Peróxido de Hidrogênio/química , Compostos de Manganês , Óxidos , Clareamento Dental/métodos
4.
Dent Mater ; 38(4): 655-669, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35210124

RESUMO

OBJECTIVE: In this paper we propose the association of ß-glycerophosphate (ßGP) and calcium-hydroxide with chitosan (CH) to formulate a porous bioactive scaffold suitable as a cell-homing platform for dentin regeneration. METHODS: Calcium hydroxide and ßGP solutions were incorporated into chitosan to modulate scaffold architecture and composition by a phase separation technique. Architecture, chemical composition, and degradability were evaluated, and biological characterizations were performed by the seeding of dental pulp cells (DPCs) onto scaffolds, or by cultivating them in contact with leachable components (extracts), to determine cytocompatibility and odontoblastic differentiation. Cell-free scaffolds were then positioned in intimate contact with a 3D culture of DPCs in a pulp-in-a-chip platform under simulated pulp pressure. Cell mobilization and odontoblastic marker expression were evaluated. Deposition of mineralized matrix was assessed in direct contact with dentin, in the absence of osteogenic factors. RESULTS: Incorporation of calcium hydroxide and ßGP generated a stable porous chitosan scaffold containing Ca-P nanoglobule topography (CH-Ca-ßGP), which favored cell viability, alkaline phosphatase activity, and mineralized matrix deposition by cells seeded onto the scaffold structure and at a distance. The pulp-in-a-chip assay denoted its chemotactic and bioactive potential, since dentin sialoprotein-positive DPCs from 3D culture adhered to CH-Ca-ßGP more than to plain chitosan. The higher deposition of mineralized matrix onto the scaffold and surrounding dentin was also observed. SIGNIFICANCE: A CH-Ca-ßGP scaffold creates a microenvironment capable of mobilizing DPC migration toward its structure, harnessing the odontogenic potential and culminating in the expression of a highly mineralizing phenotype, key factors for a cell-homing strategy.


Assuntos
Quitosana , Polpa Dentária , Hidróxido de Cálcio , Diferenciação Celular , Células Cultivadas , Quitosana/química , Quitosana/farmacologia , Dentina , Regeneração , Alicerces Teciduais/química
5.
Oper Dent ; 47(1): 87-96, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624102

RESUMO

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.


Assuntos
Colagem Dentária , Adesivos Dentinários , Animais , Resinas Compostas/química , Cimentos Dentários , Dentina , Adesivos Dentinários/química , Teste de Materiais , Camundongos , Cimentos de Resina/química , Temperatura , Resistência à Tração
6.
Oper Dent ; 46(6): E251-E263, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34919726

RESUMO

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.


Assuntos
Colagem Dentária , Adesivos Dentinários , Colágeno , Resinas Compostas/química , Resinas Compostas/uso terapêutico , Colagem Dentária/métodos , Cimentos Dentários/uso terapêutico , Dentina , Adesivos Dentinários/química , Adesivos Dentinários/uso terapêutico , Teste de Materiais , Cimentos de Resina/química , Cimentos de Resina/uso terapêutico , Resistência à Tração
7.
J Dent Res ; 100(10): 1118-1126, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34315311

RESUMO

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.


Assuntos
Quitosana , Animais , Cálcio , Diferenciação Celular , Polpa Dentária , Dentina , Odontoblastos , Ratos , Sinvastatina/farmacologia
8.
Biomed Pharmacother ; 130: 110592, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32763822

RESUMO

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.


Assuntos
Antituberculosos/uso terapêutico , Oxidiazóis/uso terapêutico , Tuberculose/tratamento farmacológico , Animais , Antituberculosos/farmacologia , Antituberculosos/toxicidade , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Testes de Mutagenicidade , Mycobacterium tuberculosis/efeitos dos fármacos , Oxidiazóis/farmacologia , Oxidiazóis/toxicidade , Tuberculose/microbiologia
9.
Oper Dent ; 45(6): 632-642, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32516400

RESUMO

CLINICAL RELEVANCE: Pigments in tooth structures affect the diffusion of H2O2 through enamel and dentin. The bleaching methodology can be impacted. SUMMARY: Objective: The aim of this study was to evaluate the influence of the presence of pigments in tooth structures on the trans-enamel and trans-dentin diffusion of hydrogen peroxide (H2O2) and its cytotoxicity after carrying out an in-office bleaching therapy.Methods and Materials: A bleaching gel with 35% H2O2 was applied for 45 minutes (three times for 15 minutes) on enamel and dentin discs (n=6), either previously submitted to the intrinsic pigmentation protocol with a concentrated solution of black tea, or not, defining the following groups: G1, unbleached untreated discs (control 1); G2, unbleached pigmented discs (control 2); G3, bleached untreated discs; G4, bleached pigmented discs. The discs were adapted to artificial pulp chambers, which were placed in wells of 24-well plates containing 1 mL culture medium (Dulbecco's modified Eagle's medium [DMEM]). After applying the bleaching gel on enamel, the extracts (DMEM + components of bleaching gel that diffused through the discs) were collected and then applied on the cultured MDPC-23 odontoblast-like cells. Cell viability (methyl tetrazolium assay and Live & Dead, Calcein AM, and ethidium homodimer-1 [EthD-1] probes), the amount of H2O2 that diffused through enamel and dentin (leuco-crystal violet product), and the H2O2-mediated oxidative cell stress (SOx) and components of degradation were assessed (analysis of variance/Tukey; α=0.05).Results: There was no significant difference between the groups G1 and G2 for all the parameters tested (p>0.05). Reduction in the trans-enamel and trans-dentin diffusion of H2O2 occurred for G4 in comparison with G3. Significantly lower cell viability associated with greater oxidative stress was observed for G3 (p<0.05). Therefore, in-office tooth bleaching therapy performed in pigmented samples caused lower cytotoxic effects compared with untreated samples submitted to the same esthetic procedure (p<0.05).Conclusion: According to the methodology used in this investigation, the authors concluded that the presence of pigments in hard tooth structures decreases the trans-enamel and trans-dentin diffusion of H2O2 and the toxicity to pulp cells of an in-office bleaching gel with 35% H2O2.


Assuntos
Clareadores Dentários , Clareamento Dental , Dentina , Peróxido de Hidrogênio/toxicidade , Pigmentação , Clareamento Dental/efeitos adversos , Clareadores Dentários/toxicidade
10.
Int J Biol Macromol ; 158: 197-207, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32360468

RESUMO

This paper explores different film assembly conditions of the polyelectrolyte solutions of hyaluronan (HA) and chitosan (CHI), as well as both substrate and cell surface modifications, to investigate PC3 cells adhesion properties. UV-Visible, AFM-IR and Zeta potential techniques indicate that the solution ionic strength is a relevant parameter to modulate the free carboxylic groups of HA on the film surface. In addition, capacitive coupling measurements suggest that assembly conditions that favor surface charge mobility inhibit cell adhesion due to polymer rearrangements that support non-specific electrostatic interactions of positively charged CHI residues and the negatively charged cell moieties, rather than specific CD44-hyaluronan interactions. Moreover, the PC3 cells treatment with hyaluronidase and anti-CD44 antibody also highlighted the importance of CD44 binding site availability on the tumor cell adhesion properties. Finally, the conjugation of wheat germ agglutinin on the film surface proved to be a suitable strategy to boost the PC3 cell adhesion properties. Our results reveal the remarkable capacity of HA/CHI films to modulate cell-substrate properties, which pave the road for the development of surfaces suitable for several applications based on biosensing.

11.
Rev. argent. reumatol ; 30(2): 33-35, jun. 2019. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1041883

RESUMO

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.


Assuntos
Artrite Reumatoide , Psoríase , Abatacepte
12.
Astrobiology ; 19(9): 1123-1138, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31084501

RESUMO

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.


Assuntos
Elétrons , Glicina/efeitos da radiação , Temperatura , Cristalografia por Raios X , Glicina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo
13.
Oper Dent ; 44(4): 414-423, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30444688

RESUMO

OBJECTIVES: The aim of this study was to evaluate the effect of horseradish peroxidase (HRP) on the release of free radicals, bleaching effectiveness, and indirect cytotoxicity of a 35% hydrogen peroxide (HP) bleaching gel. METHODS AND MATERIALS: First, HP degradation rates and free radical release were evaluated for 35% HP in contact or not with HRP (10 mg/mL). The bleaching gel associated or not with HRP was then applied (3 × 15 minutes) to enamel/dentin discs adapted to artificial pulp chambers, and the culture medium in contact with dentin surfaces (extract) was collected and exposed to cultured odontoblast-like cells. Membrane damage and viability of cells as well as oxidative stress were evaluated. Residual HP/free radical diffusion was quantified, and bleaching effectiveness (ΔE) was assessed. Unbleached discs served as negative controls. RESULTS: The addition of HRP to the 35% HP bleaching gel enhanced the release of free radicals in comparison with plain HP gel. The 35% HP-mediated cytotoxicity significantly decreased with HRP in the bleaching gel and was associated with reduced HP/free radical diffusion through the enamel/dentin discs. ΔE values increased every bleaching session for HRP-containing gel relative to positive control, accelerating the whitening outcome. CONCLUSION: The enzymatic activation of a 35% HP bleaching gel with HRP accelerated HP degradation mediated by intensification of free radical release. This effect optimized whitening outcome as well as minimized residual HP and free radical diffusion through enamel and dentin, decreasing the harmful effects on odontoblast-like cells.


Assuntos
Clareadores Dentários , Clareamento Dental , Polpa Dentária , Géis , Peróxido de Hidrogênio
14.
J Dev Orig Health Dis ; 9(4): 373-376, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29559019

RESUMO

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.


Assuntos
Colocasia/química , Farinha , Epitélio Seminífero/citologia , Epitélio Seminífero/metabolismo , Células de Sertoli/metabolismo , Testosterona/metabolismo , Animais , Masculino , Ratos , Ratos Wistar , Epitélio Seminífero/efeitos dos fármacos , Células de Sertoli/citologia , Células de Sertoli/efeitos dos fármacos
15.
J Ethnopharmacol ; 213: 21-25, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29037916

RESUMO

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.


Assuntos
Amaranthaceae , Anti-Inflamatórios/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/genética , Mucinas/genética , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/uso terapêutico , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/genética , Colite/patologia , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Glucuronidase/genética , Masculino , Extratos Vegetais/uso terapêutico , Raízes de Plantas , RNA Mensageiro/metabolismo , Ratos Wistar , Ácido Trinitrobenzenossulfônico
16.
Sci Rep ; 7(1): 13982, 2017 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-29070908

RESUMO

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.

17.
J Dent Res ; 96(13): 1518-1525, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28759300

RESUMO

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.


Assuntos
Polpa Dentária/citologia , Odontoblastos/enzimologia , Receptor PAR-1/metabolismo , Receptor PAR-2/metabolismo , Adulto , Western Blotting , Cromatografia Líquida de Alta Pressão , Citometria de Fluxo , Humanos , Inflamação/metabolismo , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Microscopia Confocal , RNA Mensageiro/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Regulação para Cima
18.
Photochem Photobiol Sci ; 16(8): 1336-1337, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28741639

RESUMO

Correction for 'In vivo evaluation of photodynamic inactivation using Photodithazine® against Candida albicans' by J. C. Carmello, et al., Photochem. Photobiol. Sci., 2015, 14, 1319-1328.

19.
Clin Oral Investig ; 21(8): 2509-2520, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28091877

RESUMO

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.


Assuntos
Esmalte Dentário/efeitos dos fármacos , Estética Dentária , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/toxicidade , Clareadores Dentários/farmacologia , Clareadores Dentários/toxicidade , Clareamento Dental/métodos , Fosfatase Alcalina/análise , Biomarcadores/análise , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Polpa Dentária/citologia , Géis , Humanos , Técnicas In Vitro , Odontoblastos/efeitos dos fármacos , Estresse Oxidativo , Fatores de Tempo
20.
Int Endod J ; 50(6): 549-559, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27238557

RESUMO

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.


Assuntos
Células-Tronco/citologia , Esfoliação de Dente/metabolismo , Dente Decíduo/citologia , Sobrevivência Celular , Dentina/efeitos da radiação , Humanos , Luz , Células-Tronco/efeitos da radiação , Dente Decíduo/efeitos da radiação
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