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1.
Cir Cir ; 87(S1): 8-16, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31501623

RESUMO

Background: Procedures to remove adiposities and skin, such as dermolipectomy, can develop wounds that are difficult to heal by conventional therapies. Mesenchymal stem cells are indicated as potential candidates for regenerative therapy in wounds, due to their multipotentiality, low immunogenicity, modulating capacity of inflammation and tissue modeling processes. Case report: Patient with dehiscent chronic ulcer secondary to dermolipectomy, who received cutaneous treatment with mesenchymal stem cells. The therapy induced scar formation and neovascularization, as well as the decrease of infiltrated leukocytes and proinflammatory cytokines. Mesenchymal cells are proposed as an interesting alternative for the treatment of postoperative lesions.

2.
Braz. dent. j ; 30(4): 410-416, July-Aug. 2019. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-1011567

RESUMO

Abstract The present study aimed to analyze the effect of LED phototherapy on the presence of hyalinization and root resorption during orthodontic tooth movement (OTM) in rats and to measure the amount of tooth movement. Eighty rats were allocated into two groups: LED and control (CON), where the LED rats were irradiated with infrared LED (850 nm, 30 mW) for 5 min during the first five days of OTM and where controls were not irradiated. Both groups were subdivided into four subgroups (n=10) according to the date of euthanasia (4, 7, 14 and 21 days). Five out of ten LED21 and five of ten CON21 rats were submitted to micro-computed tomography (μCT); μCT scans were taken on days 0, 7, 14 and 21. For histological study, maxillae were processed to light microscopy using Hematoxylin-Eosin (HE) and Tartrate-Resistant Acid Phosphatase (TRAP) histochemistry. The amount of tooth movement did not differ between LED and CON. Hyalinization was observed at the pressure areas in both groups, and it did not show a statistically significant difference between the groups. Root resorption was also observed in both groups after 7 days and it did not represent any differences between the two groups. LED phototherapy was not able to increase the amount of OTM. Similar characteristics of hyalinization and root resorption were observed in both groups.


Resumo O presente estudo tem como objetivo analisar o efeito da fototerapia LED na presença da hialinização e reabsorção radicular durante o movimento dentário ortodôntico (MDO) em ratos, e a mensuração da quantidade de movimento dentário. Oitenta ratos foram alocados em dois grupos: LED e Controle (CON), os ratos foram irradiados com um LED infravermelho (850nm, 30mW) por 5 minutos durante os cinco primeiros dias da MDO; e o grupo controle não foi irradiado. Ambos os grupos foram subdivididos em 4 subgrupos (n=10) de acordo com a data da eutanásia (4, 7, 14 e 21 dias). Cinco dos dez ratos LED21 e cinco dos dez ratos CON21foram submetidos a microtomografia computadorizada (μCT); As μCT foram realizadas nos dias 0, 7, 14 e 21. Para o estudo histológico, as maxilas foram processadas para microscopia de luz, usando hematoxilina-eosina (HE) e Fosfatase ácido Tartrate-Resistente (TRAP) para histoquímica. A quantidade de movimento dentário não diferiu entre o LED e o CON. A hialinização foi observada nas áreas de pressão em ambos os grupos e não mostrou diferença estatisticamente significante. Reabsorção radicular também foi observada em ambos os grupos depois de 7 dias e não houve diferença entre os grupos. A fototerapia LED não aumentou a quantidade de MDO. Características similares de hialinização e reabsorção radicular foram observadas em ambos os grupos

3.
Sci Rep ; 9(1): 10562, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31332205

RESUMO

This study describes the effect of the software binning and data averaging during micro CT volume acquisition, on the assessment of root resorption volumes. The mesial roots (n = 9), after orthodontic tooth movement during 14 days, were scanned, using a micro CT system (9 µm/pixel). All roots were reconstructed and the volumes of the resorption lacunae evaluated. The height and width of the pixels vary according to the parameters (A1, A2, A3, A4, A5, A6, A7, A8, A9) used during the scan. In the root #1 the mean volumes of resorption were similar in A4 and A7; in the root #2 there was no similarity in the mean volumes of resorption in any of the parameters; in root #3 only A4 presented mean volume different from zero (3.05 × 10°). In the root #5, the A1 and A7 presented similar mean volumes and in the A6 and A9 presented near mean volumes. In the root #9 the A1, A4, and A7 presented similar mean volumes and A6 and A9 also had similar mean volumes. Significant difference was detected in the volume of resorption among the roots #2, #5 and #9 (p = 0.04). When analyzing delicate structures such as the roots of rats' molars, the variation of such parameters will significantly influence the results.

4.
Braz Dent J ; 30(4): 410-416, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31340233

RESUMO

The present study aimed to analyze the effect of LED phototherapy on the presence of hyalinization and root resorption during orthodontic tooth movement (OTM) in rats and to measure the amount of tooth movement. Eighty rats were allocated into two groups: LED and control (CON), where the LED rats were irradiated with infrared LED (850 nm, 30 mW) for 5 min during the first five days of OTM and where controls were not irradiated. Both groups were subdivided into four subgroups (n=10) according to the date of euthanasia (4, 7, 14 and 21 days). Five out of ten LED21 and five of ten CON21 rats were submitted to micro-computed tomography (µCT); µCT scans were taken on days 0, 7, 14 and 21. For histological study, maxillae were processed to light microscopy using Hematoxylin-Eosin (HE) and Tartrate-Resistant Acid Phosphatase (TRAP) histochemistry. The amount of tooth movement did not differ between LED and CON. Hyalinization was observed at the pressure areas in both groups, and it did not show a statistically significant difference between the groups. Root resorption was also observed in both groups after 7 days and it did not represent any differences between the two groups. LED phototherapy was not able to increase the amount of OTM. Similar characteristics of hyalinization and root resorption were observed in both groups.

5.
Acta Histochem ; 121(6): 680-689, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31213291

RESUMO

Despite the success for the treatment of melanoma such as targeted molecular therapy, the use of such treatments are expensive For this reason, this study was carried out to explore the anti-cancer properties of available drugs that are able to modify the melanoma prognosis. The study was conducted in two phases: Evaluation of pharmacological effects of pentoxifylline (PTX) administered above (60 mg/kg) which is the therapeutic dose that is aimed at reducing the side-effect of radiotherapy, and of α- galactosylceramide (GalCer) administered at 100 µg/kg, as well as their combination using a murine model (BDF1 mice) of melanoma cell line (B16-F1, ATCC). For the radiotherapy phase, 9 Gy was applied in the tumor area, before (3 days), during (30 min) and after (3 days) the PTX + GalCer treatment. In both study phases, the mitosis rate, leukocyte infiltration and necro-apoptosis were assessed using histological and immunohistochemical approach and tumor volume evaluation as biomarkers. All treatments showed good prognosis results estimated as reduction of mitosis rate (PTX + GalCer after radiotherapy and GalCer), increased leukocyte infiltrate (PTX + GalCer after radiotherapy and GalCer) and necro-apoptosis augmentation (PTX + GalCer after radiotherapy and radiotherapy control). Nevertheless, a lower development of tumor volume was found in GalCer treatment. In this way, it is possible to suggest that the integrated treatment with immuno-stimulators such as GalCer, plus drug used for peripheral vascular disease (PTX) after radiotherapy is probably an alternative for controlling aggressive melanoma in murine model.

6.
Angle Orthod ; 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30920868

RESUMO

OBJECTIVES:: To investigate the effects of irradiation lasers and light-emitting diode (LED) light on root resorption in rat molars during orthodontic tooth movement (OTM). MATERIALS AND METHODS:: Twenty-one 12-week-old Wistar male rats were divided into three groups: OTM only (control [CG]), OTM and LED irradiation (DG), and OTM and low laser irradiation therapy (LG). The distance between the first and second molars was used to evaluate the amount of tooth movement. The mesial surfaces of the distopalatal roots were analyzed by scanning electron microscopy, and the area of the resorption was calculated. RESULTS:: Statistical analysis showed a decreased amount of tooth movement in the exposed DG or LG compared with CG, which was statistically significant ( P = .031 and P = .004, respectively). However, when the DG and LG groups were compared, no statistically significant differences were found ( P = .504). The root resorption areas were similar between CG and DG. However, statistically significant differences were found between LG and CG ( P = .014) and LG and DG ( P = .038). CONCLUSIONS:: Phototherapy did not enhance tooth movement, while infrared laser irradiation did increase root resorption.

7.
Methods Mol Biol ; 1922: 325-332, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30838587

RESUMO

This chapter describes laboratory protocols for TEM and SEM approaches allowing the examination of the dental hard tissues' constituents at the ultrastructural level. TEM has the highest resolution power to examine the cellular and extracellular matrix ultrastructure inside a given sample, detecting the presence, location, and quantification of organelles related to the metabolism of the cell type as well as membrane specializations. SEM allows the observation of the sample surface, for examining dimensional topography and distribution of exposed features.


Assuntos
Microscopia Eletrônica de Varredura/métodos , Microscopia Eletrônica de Transmissão/métodos , Dente/ultraestrutura , Animais , Dessecação/métodos , Humanos , Microtomia/métodos , Inclusão do Tecido/métodos , Fixação de Tecidos/métodos
8.
Horiz. méd. (Impresa) ; 19(1): 81-86, ene.-mar. 2019. ilus, tab
Artigo em Espanhol | LILACS-Express | ID: biblio-1012273

RESUMO

La leptospirosis humana es una enfermedad causada por bacterias del género Leptospira. Las leptospiras infectan al organismo a través de la piel y mucosas lesionadas. En el sitio de ingreso producen poca reacción inflamatoria local. Los síntomas clínicos varían desde un cuadro parecido a la gripe, hasta ictericia o incluso falla renal y hepática, y están asociados con altas tasas de mortalidad. Se sabe que hay una infección transplacentaria que puede provocar un aborto espontáneo, muerte fetal o leptospirosis congénita. El aborto espontáneo es más común si la infección ocurre en los primeros meses del embarazo. El objetivo de este reporte de caso es dar a conocer la presentación, manifestaciones y abordaje terapéutico en cuidados intensivos de un recién nacido con antecedente materno de leptospirosis en el primer trimestre de embarazo, así como la revisión de la literatura con estructura de búsqueda sistemática


Human leptospirosis is a disease caused by bacteria of the genus Leptospira. Leptospiras infect the body through the skin and damaged mucous membranes. At the site of admission, they produce little local inflammatory reaction. Clinical symptoms range from flu-like symptoms to jaundice or even kidney and liver failure, and are associated with high mortality rates. It is known that there is a transplacental infection that can cause miscarriage, fetal death or congenital leptospirosis. Miscarriage is more common if the infection occurs in the first months of pregnancy. The objective of this case report is to disclose the presentation, manifestations and therapeutic approach in intensive care of a newborn infant with maternal history of leptospirosis in the first trimester of pregnancy, as well as the review of the literature using a systematic search

9.
J. appl. oral sci ; 27: e20180044, 2019. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-975876

RESUMO

Abstract Radiation-related caries are one the most undesired reactions manifested during or after head and neck radiotherapy. Fluoride application is an important strategy to reduce demineralization and enhance remineralizaton. Objective: To evaluate the effect of the topical application of fluoride during irradiation on dental enamel demineralization. Material and Methods: Thirty molars were randomly divided into three groups: Non-irradiated (NI), Irradiated (I), Irradiated with fluoride (IF). Each group was subdivided according to the presence or absence of pH-cycling (n=5). In the irradiated groups, the teeth received 70 Gy. The enamel's chemical composition was measured using Fourier Transform Infrared Spectrometry (organic matrix/mineral ratio - M/M and relative carbonate content - RCC). Vickers microhardness (VHN) and elastic modulus (E) were evaluated at three depths (surface, middle and deep enamel). Scanning electron microscopy (SEM) was used to assess the enamel's morphology. Results: The FTIR analysis (M/M and RCC) showed significant differences for irradiation, pH-cycling and the interaction between factors (p<0.001). Without pH-cycling, IF had the lowest organic matrix/mineral ratio and relative carbonate content. With pH-cycling, the organic matrix/mineral ratio increased and the relative carbonate content decreased, except for IF. VHN was influenced only by pH-cycling (p<0.001), which generated higher VHN values. ANOVA detected significant differences in E for irradiation (p<0.001), pH-cycling (p<0.001) and for the interaction between irradiation and pH-cycling (p<0.001). Increased E was found for group I without pH-cycling. With pH-cycling, groups I and IF were similar, and showed higher values than NI. The SEM images showed no morphological changes without pH-cycling. With pH-cycling, fluoride helped to maintain the outer enamel's morphology. Conclusions: Fluoride reduced mineral loss and maintained the outer morphology of irradiated and cycled enamel. However, it was not as effective in preserving the mechanical properties of enamel. Radiotherapy altered the enamel's elastic modulus and its chemical composition.

10.
J Appl Oral Sci ; 27: e20180044, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30540070

RESUMO

OBJECTIVE: Radiation-related caries are one the most undesired reactions manifested during or after head and neck radiotherapy. Fluoride application is an important strategy to reduce demineralization and enhance remineralizaton. To evaluate the effect of the topical application of fluoride during irradiation on dental enamel demineralization. MATERIAL AND METHODS: Thirty molars were randomly divided into three groups: Non-irradiated (NI), Irradiated (I), Irradiated with fluoride (IF). Each group was subdivided according to the presence or absence of pH-cycling (n=5). In the irradiated groups, the teeth received 70 Gy. The enamel's chemical composition was measured using Fourier Transform Infrared Spectrometry (organic matrix/mineral ratio - M/M and relative carbonate content - RCC). Vickers microhardness (VHN) and elastic modulus (E) were evaluated at three depths (surface, middle and deep enamel). Scanning electron microscopy (SEM) was used to assess the enamel's morphology. RESULTS: The FTIR analysis (M/M and RCC) showed significant differences for irradiation, pH-cycling and the interaction between factors (p<0.001). Without pH-cycling, IF had the lowest organic matrix/mineral ratio and relative carbonate content. With pH-cycling, the organic matrix/mineral ratio increased and the relative carbonate content decreased, except for IF. VHN was influenced only by pH-cycling (p<0.001), which generated higher VHN values. ANOVA detected significant differences in E for irradiation (p<0.001), pH-cycling (p<0.001) and for the interaction between irradiation and pH-cycling (p<0.001). Increased E was found for group I without pH-cycling. With pH-cycling, groups I and IF were similar, and showed higher values than NI. The SEM images showed no morphological changes without pH-cycling. With pH-cycling, fluoride helped to maintain the outer enamel's morphology. CONCLUSIONS: Fluoride reduced mineral loss and maintained the outer morphology of irradiated and cycled enamel. However, it was not as effective in preserving the mechanical properties of enamel. Radiotherapy altered the enamel's elastic modulus and its chemical composition.


Assuntos
Cariostáticos/farmacologia , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/efeitos da radiação , Fluoretos Tópicos/farmacologia , Desmineralização do Dente/prevenção & controle , Análise de Variância , Cariostáticos/química , Cariostáticos/efeitos da radiação , Módulo de Elasticidade , Fluoretos Tópicos/química , Fluoretos Tópicos/efeitos da radiação , Testes de Dureza , Humanos , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Radioterapia/efeitos adversos , Distribuição Aleatória , Valores de Referência , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Desmineralização do Dente/etiologia
11.
Nucleic Acids Res ; 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30395280

RESUMO

RegulonDB, first published 20 years ago, is a comprehensive electronic resource about regulation of transcription initiation of Escherichia coli K-12 with decades of knowledge from classic molecular biology experiments, and recently also from high-throughput genomic methodologies. We curated the literature to keep RegulonDB up to date, and initiated curation of ChIP and gSELEX experiments. We estimate that current knowledge describes between 10% and 30% of the expected total number of transcription factor- gene regulatory interactions in E. coli. RegulonDB provides datasets for interactions for which there is no evidence that they affect expression, as well as expression datasets. We developed a proof of concept pipeline to merge binding and expression evidence to identify regulatory interactions. These datasets can be visualized in the RegulonDB JBrowse. We developed the Microbial Conditions Ontology with a controlled vocabulary for the minimal properties to reproduce an experiment, which contributes to integrate data from high throughput and classic literature. At a higher level of integration, we report Genetic Sensory-Response Units for 200 transcription factors, including their regulation at the metabolic level, and include summaries for 70 of them. Finally, we summarize our research with Natural language processing strategies to enhance our biocuration work.

12.
Vet Comp Orthop Traumatol ; 31(6): 405-412, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30352475

RESUMO

OBJECTIVE: The main purpose of this study was to evaluate the characteristics of a vegetal polymeric biomaterial intended for bone substitution in horses and to investigate the responses of the equine third metacarpal bone to biomaterial implantation. MATERIALS AND METHODS: Six horses were submitted to osteotomy on the dorsal aspect of the left and right third metacarpal bones; one bone defect was randomly selected for treatment with biopolymer, while the other was left untreated and served as a control. Bone density was monitored radiographically after surgery and bone biopsy fragments were collected at the end of the 120-day follow-up period. Biopsy fragments were analysed using light and scanning electron microscopy. RESULTS: Mean bone density values (mmAL) were greater in control defects (16.33 ± 1.6) than in polymer-treated defects (14.17 ± 1.7) at 120 days (p = 0.027). Light microscopy revealed greater percentages of new bone formation in control defects (50.15 ± 14.8) than in polymer treated defects (26.94 ± 12.1) at 120 days (p < 0.0001). Scanning electron microscopy analysis suggested a similar quality of pre-existing bone and new bone formed in the presence of biomaterial. CLINICAL SIGNIFICANCE: The absence of adverse reactions supports biomaterial biocompatibility and osteoconducting capacity and suggests the castor oil polymer is a suitable bone substitute for the treatment of bone defects in horses.


Assuntos
Substitutos Ósseos/uso terapêutico , Óleo de Rícino/uso terapêutico , Ossos Metacarpais/cirurgia , Animais , Materiais Biocompatíveis/uso terapêutico , Densidade Óssea , Regeneração Óssea/efeitos dos fármacos , Cavalos/cirurgia , Masculino , Ossos Metacarpais/diagnóstico por imagem , Ossos Metacarpais/ultraestrutura , Microscopia Eletrônica de Varredura/veterinária , Osteotomia/veterinária , Polímeros/uso terapêutico , Radiografia
13.
J Appl Oral Sci ; 26: e20170626, 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30304125

RESUMO

OBJECTIVE: The purpose of this study was to histologically evaluate pulp and dentin under induced tooth movement (ITM) with different types of forces. MATERIAL AND METHODS: The maxillary right first molars of rats were submitted to movement with continuous (CF), continuous interrupted (CIF) and intermittent (IF) forces during 5, 7 and 9 days with nickel-titanium (NiTi) closed-coil springs exerting 50cN force magnitude. The groups were histologically evaluated as for cellularity pattern, presence of dystrophic, hemodynamic alterations in the pulp as well dentin alterations. The main observed alterations were related to hemodynamic pulp characteristics, such as presence of thrombosis, vascular congestion and hemorrhages. The hemodynamic alterations were statistically evaluated by Shapiro-Wilk normality test and analysis of variance by the Kruskall-Wallis test. RESULTS: There was no significant differences observed between groups in the different types of applied forces and duration of ITM (vascular congestion, p=1.000; hemorrhage, p=0.305; thrombosis, p=1.000). CONCLUSIONS: Pulp tissue alterations resulting from ITM were limited to hemodynamic events, without progressing to irreversible degeneration, regardless of the type of force applied.


Assuntos
Polpa Dentária/patologia , Dentina/patologia , Técnicas de Movimentação Dentária/efeitos adversos , Animais , Polpa Dentária/irrigação sanguínea , Masculino , Modelos Animais , Necrose , Ratos Wistar , Fatores de Tempo
14.
Commun Biol ; 1: 173, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30374463

RESUMO

Dermal interstitial fluid (ISF) is an underutilized information-rich biofluid potentially useful in health status monitoring applications whose contents remain challenging to characterize. Here, we present a facile microneedle approach for dermal ISF extraction with minimal pain and no blistering for human subjects and rats. Extracted ISF volumes were sufficient for determining transcriptome, and proteome signatures. We noted similar profiles in ISF, serum, and plasma samples, suggesting that ISF can be a proxy for direct blood sampling. Dynamic changes in RNA-seq were recorded in ISF from induced hypoxia conditions. Finally, we report the first isolation and characterization, to our knowledge, of exosomes from dermal ISF. The ISF exosome concentration is 12-13 times more enriched when compared to plasma and serum and represents a previously unexplored biofluid for exosome isolation. This minimally invasive extraction approach can enable mechanistic studies of ISF and demonstrates the potential of ISF for real-time health monitoring applications.

15.
Artigo em Inglês | MEDLINE | ID: mdl-30091514

RESUMO

This study describes the synthesis of dicalcium phosphate dihydrate (DCPD) particles in the presence of different ethylene glycol dimethacrylates (EGDMA, ethylene glycol/EG units: 1, 2, 3 or 4) at two monomer-to-ammonium phosphate molar ratios (1:1 and 2:1), as a strategy to develop CaP-monomer particles with improved interaction with resin matrices. Particles displaying high surface areas and organic contents were added to a photocurable BisGMA-TEGDMA resin and the resulting materials were tested for degree of conversion (DC), biaxial flexural strength (BFS), flexural modulus, and ion release. Data were subjected to one-way ANOVA or Kruskal-Wallis/Dunn test (alpha: 0.05). Functionalization with EGDMA derivatives was dependent upon the length of the spacer group and monomer concentration in the synthesis. No differences in DC were observed among materials (p > 0.05). A 39% increase in BFS was obtained with the use of particles with the highest functionalization level compared to non-functionalized particles (p < 0.001). The use of functionalized DCPD reduced flexural modulus in comparison to non-functionalized particles (p < 0.001). Calcium release was similar among materials and remained constant during the experiment, while phosphate release was higher at 7 days in comparison to the remaining weeks (p < 0.001). In conclusion, diethylene glycol dimethacrylate resulted in the highest functionalization levels and the highest BFS among DCPD-containing materials. Ion release was not affected by functionalization. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2018.

16.
J Appl Oral Sci ; 26: e20170437, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29791567

RESUMO

Tissue bioengineering has been applied to Endodontics to seek a more biological treatment. The presence of blood vessels is crucial for cell nutrition during tissue formation. Objective This study analysed the application of vascular endothelial growth factor (VEGF) in the angiogenesis of mature root canals. Material and methods Upper first molars of twelve 13-week old Wistar male rats were used. The root pulp of the mesiobuccal canal was removed and the root canal instrumented with K-files up to size #25. Periapical bleeding was induced into the root canal by introducing a #15 K-file beyond the apex. The teeth on the right side of the arch were filled up with blood clot (G1), whereas those on the left side were filled up with blood clot plus 50 ng/ml of VEGF (G2). Teeth were sealed with light-curing glass-ionomer cement and the animals were sacrificed after 60 days. The maxilla was dissected and fixed before obtaining serial sections for histological processing with haematoxylin-eosin (HE) and immunohistochemical factor-VIII. Immunohistochemical labelling was evaluated using scores for statistical analysis. Results Immunohistological analysis demonstrated the presence of angiogenesis in both groups, but with higher angiogenic maturation in G2 during the experimental period (p<0.05). HE staining showed connective tissue with absence of odontoblasts in all specimens. Conclusions It can be concluded that it is possible to obtain angiogenesis in mature root canals with or without the use of VEGF, although the latter tends to accelerate blood vessel formation.


Assuntos
Cavidade Pulpar/irrigação sanguínea , Neovascularização Fisiológica/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/farmacologia , Animais , Bioengenharia , Coagulação Sanguínea/fisiologia , Cavidade Pulpar/efeitos dos fármacos , Imuno-Histoquímica , Masculino , Ratos Wistar , Reprodutibilidade dos Testes , Tratamento do Canal Radicular/métodos , Fatores de Tempo , Resultado do Tratamento
17.
Arch Oral Biol ; 91: 1-8, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29621667

RESUMO

OBJECTIVE: Three-dimensional (3D) cell culture methods are of high importance to studies of biological processes. This is particularly the case with spheroid cultures, which create 3D cell aggregates without the use of exogenous materials. Compared to conventional monolayer cultures, cellular spheroid cultures have been demonstrated to improve multilineage potential and extracellular matrix production. To address this issue in depth, we present a more comprehensive analysis of 3D human dental pulp cell (hDPC) spheroids. DESIGN: hDPC spheroids were fabricated by the pellet culture method and were cultured without adding any reagent to induce differentiation. The gene-expression profiles of the 3D and two-dimensional (2D) cultured hDPCs were compared by complementary DNA microarray analysis. Odontoblastic and osteoblastic differentiation marker gene expression was evaluated by quantitative real-time PCR (RT-qPCR). Hematoxylin-eosin (HE) staining and transmission electron microscopy (TEM) were applied to examine the morphology of hDPC spheroids and extracellular matrix components. RESULTS: Compared with 2D monolayer culture, microarray analysis identified 405 genes and 279 genes with twofold or greater differential expression after 3 days and 28 days of 3D culture, respectively. In 3D hDPC spheroids, gene ontology analysis revealed upregulation of extracellular matrix-related genes and downregulation of cell growth-related genes. RT-qPCR analysis showed higher expression levels of osteocalcin, dentin sialophosphoprotein, and alkaline phosphatase. TEM revealed the morphological characteristics of the fibrillar collagen-rich matrix and cell-cell interactions. CONCLUSIONS: The present findings provide clues to understanding the mechanisms of pellet-cultured hDPCs and contribute to future research in the comparative studies of different 3D culture methods.


Assuntos
Técnicas de Cultura de Células/métodos , Polpa Dentária/citologia , Polpa Dentária/fisiologia , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Proliferação de Células/genética , Proliferação de Células/fisiologia , Células Cultivadas , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Humanos , Microscopia Eletrônica de Transmissão , Odontoblastos/citologia , Osteocalcina/genética , Osteocalcina/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Sialoglicoproteínas/genética , Sialoglicoproteínas/metabolismo , Transcriptoma
18.
Dent Mater ; 34(5): 746-755, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29422326

RESUMO

OBJECTIVES: This study describes the synthesis of brushite nanoparticles (CaHPO4·2H2O) functionalized with triethylene glycol dimethacrylate (TEGDMA) and their application in dental restorative composites with remineralizing capabilities. METHODS: Nanoparticles were synthesized, with TEGDMA being added to one of the precursor solutions at three different molar ratios (0:1, 0.5:1 and 1:1, in relation to the ammonium phosphate precursor). Then, they were added (10 vol%) to a photocurable dimethacrylate matrix containing 50 vol% of reinforcing glass particles. The resulting composites were tested for degree of conversion, biaxial flexural strength and elastic modulus (after 24h and 28days in water), and ion release (over a 28-day period). Commercial composites (one microhybrid and one microfilled) were tested as controls. RESULTS: The final TEGDMA content in the functionalizing layer was modulated by the molar ratio added to the precursor solution. Functionalization reduced nanoparticle size, but did not reduce agglomeration. Improved mechanical properties were found for the composite containing nanoparticles with higher TEGDMA level in comparison to the composite containing non-functionalized nanoparticles or those with a low TEGDMA level. All brushite composites presented statistically significant reductions in strength after 28 days in water, but only the material with high-TEGDMA nanoparticles retained strength similar to the microhybrid commercial control. Overall, ion release was not affected by functionalization and presented steady levels for 28 days. SIGNIFICANCE: Though agglomeration was not reduced by functionalization, the improvement in the matrix-nanoparticle interface allowed for a stronger material, without compromising its remineralizing potential.

19.
Clin Oral Investig ; 22(2): 875-883, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28776096

RESUMO

OBJECTIVES: The objective of this study was to evaluate the biomechanical properties of dentin and the microtensile bond strength (µTBS) performed before or after radiotherapy (RT). MATERIAL AND METHODS: Dentin chemical composition (infrared spectroscopy-FTIR), SEM images, and mechanical properties (Vickers microhardness-VHN and elastic modulus-E) were evaluated comparing no irradiated and irradiate dentin (n = 5). RT was defined by application of 72 Gy (1.8 Gy daily, 5 days per week, during 8 weeks) with sample immersed in distilled water. µTBS evaluated three groups (n = 10): NI-no irradiated; IB-irradiation before restoration; and IA-irradiation after restoration. Resin-dentin sticks (1.0 mm2) were obtained and submitted to µTBS. Analysis of the bonding interface was made by confocal microscopy. RESULTS: After RT, percentage ratio of FTIR analysis showed increased absorption for all bands. SEM image showed a disorganized dentin structure. Two-way ANOVA showed increased VHN (p = 0.005) and decreased E (p < 0.001). For µTBS, one-way ANOVA and Duncan test showed significant differences among groups (p = 0.018). IB group presented the lowest bond strength values. CONCLUSIONS: RT alters the absorption bands and SEM images showed a disorganization of the dentin structure. Mechanical properties were changed with increased VHN and decreased E. µTBS was affected by the radiotherapy and restoration period (before or after). CLINICAL RELEVANCE: RT causes changes that contribute to increased risk of tooth decay. Restorative treatments can be performed using adhesive procedures, but it is preferable to be performed before of the irradiation protocol, to guarantee better adhesive properties to restoration.


Assuntos
Dentina/química , Dentina/efeitos da radiação , Análise do Estresse Dentário , Adesivos Dentinários/química , Módulo de Elasticidade , Testes de Dureza , Humanos , Técnicas In Vitro , Teste de Materiais , Microscopia Confocal , Microscopia Eletrônica de Varredura , Dente Serotino , Cimentos de Resina/química , Espectrofotometria Infravermelho , Propriedades de Superfície , Resistência à Tração
20.
J Biophotonics ; 11(4): e201700179, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29112328

RESUMO

Lipid droplet accumulation has been related to salivary gland hypofunction in diabetes. In this study, the effect of laser irradiation on the parotid glands (PGs) of diabetic rats was analyzed with regard to its effect on lipid droplet accumulation, intracellular calcium concentration and calmodulin expression. The animals were distributed into 6 groups: D0, D5, D20 and C0, C5, C20, for diabetic (D) and control animals (C), respectively. Twenty-nine days following diabetes induction, PGs of groups D5 and C5; D20 and C20 were irradiated with 5 and 20 J/cm2 of a red diode laser at 100 mW, respectively. After 24 hours, PGs were removed for histological, biochemical, and western blotting analysis. The diabetic animals showed lipid droplet accumulation, which was decreased after irradiation. Ultrastructurally, the droplets were nonmembrane bound and appeared irregularly located in the cytoplasm. Moreover, diabetic animals showed an increased intracellular calcium concentration. In contrast, after laser irradiation a progressive decrease in the concentration of this ion was observed, which would be in agreement with the results found in the increased expression of calmodulin in D20. These data are promising for using laser to decrease lipid droplet accumulation in PGs, however, more studies are necessary to better understand its mechanisms. Micrographs showing decreased lipid accumulation after laser irradiation in light micrographs (LM), and morphology of lipid droplet in transmission electron microscopic (TEM). LM: (A) PGs from nondiabetic rats that did not receive Laser irradiation (LI), (B) PGs from nondiabetic rats that received a dose of 20 J/cm2 , (C) lipid accumulation (arrows) in the secretory cells from diabetic rats that did not receive irradiation, (D) reduction of lipid accumulation in the secretory cells from diabetic rats that received a dose of 20 J/cm2 and TEM: (E) scale bar = 5 µm, (F) scale bar = 1 µm, and (G) scale bar = 0.5 µm.

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