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1.
An Acad Bras Cienc ; 93(2): e20190366, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33950151

RESUMEN

Candida spp. are naturally opportunistic and can promote infections. These yeasts can form biofilm, after penetration and adhesion to the biotic or abiotic surfaces. Preexisting diseases, treatments with drugs and radiation therapy, medical procedures, and parafunctional habits favor the installation of a fungal infection. Increased resistance to the available antifungals has become a concern. Therefore, alternative methods to control them have been evaluated, including the use of plant substances. In this study, the antibiofilm effect of R. officinalis L. extract was analyzed on C. albicans, C. dubliniensis, C. glabrata, C. krusei, and C. tropicalis. A phytochemical analysis of the extract was performed. Biofilms were formed for 48 h and exposed to the different concentrations of the extract (50, 100, and 200 mg/mL) for 5 min or 24 h. The effect of the plant extract was compared to the antifungal nystatin. Rosmarinus officinalis L. extract was constituted of phenols and flavonoids, highlighting the presence of chlorogenic acid derivatives in its composition. Biofilm reductions were observed after exposure to the plant extract for both periods. The plant extract provided a reduction similar to the antifungal. Thus, R. officinalis L. extract showed antibiofilm effect on Candida spp. comparable to the nystatin.


Asunto(s)
Candida , Rosmarinus , Antifúngicos/farmacología , Biopelículas , Candida albicans , Pruebas de Sensibilidad Microbiana , Nistatina/farmacología , Extractos Vegetales/farmacología
2.
Cochrane Database Syst Rev ; 7: CD006663, 2016 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-27454104

RESUMEN

BACKGROUND: Anderson-Fabry disease is an X-linked defect of glycosphingolipid metabolism. Progressive renal insufficiency is a major source of morbidity, additional complications result from cardio- and cerebro-vascular involvement. Survival is reduced among affected males and symptomatic female carriers.This is an update of a Cochrane review first published in 2010, and previously updated in 2013. OBJECTIVES: To evaluate the effectiveness and safety of enzyme replacement therapy compared to other interventions, placebo or no interventions, for treating Anderson-Fabry disease. SEARCH METHODS: We searched the Cystic Fibrosis and Genetic Disorders Group's Inborn Errors of Metabolism Trials Register (date of the most recent search: 08 July 2016). We also searched 'Clinical Trials' on The Cochrane Library, MEDLINE, Embase and LILACS (date of the most recent search: 24 September 2015). SELECTION CRITERIA: Randomized controlled trials of agalsidase alfa or beta in participants diagnosed with Anderson-Fabry disease. DATA COLLECTION AND ANALYSIS: Two authors selected relevant trials, assessed methodological quality and extracted data. MAIN RESULTS: Nine trials comparing either agalsidase alfa or beta in 351 participants fulfilled the selection criteria.Both trials comparing agalsidase alfa to placebo reported on globotriaosylceramide concentration in plasma and tissue; aggregate results were non-significant. One trial reported pain scores measured by the Brief Pain Inventory severity, there was a statistically significant improvement for participants receiving treatment at up to three months, mean difference -2.10 (95% confidence interval -3.79 to -0.41; at up to five months, mean difference -1.90 (95% confidence interval -3.65 to -0.15); and at up to six months, mean difference -2.00 (95% confidence interval -3.66 to -0.34). There was a significant difference in the Brief Pain Inventory pain-related quality of life at over five months and up to six months, mean difference -2.10 (95% confidence interval -3.92 to -0.28) but not at other time points. Death was not an outcome in either of the trials.One of the three trials comparing agalsidase beta to placebo reported on globotriaosylceramide concentration in plasma and tissue and showed significant improvement: kidney, mean difference -1.70 (95% confidence interval -2.09 to -1.31); heart, mean difference -0.90 (95% confidence interval -1.18 to -0.62); and composite results (renal, cardiac, and cerebrovascular complications and death), mean difference -4.80 (95% confidence interval -5.45 to -4.15). There was no significant difference between groups for death; no trials reported on pain.Only two trials compared agalsidase alfa to agalsidase beta. One of them showed no significant difference between the groups regarding adverse events, risk ratio 0.36 (95% confidence interval 0.08 to 1.59), or any serious adverse events; risk ratio 0.30; (95% confidence interval 0.03 to 2.57).Two trials compared different dosing schedules of agalsidase alfa. One of them involved three different doses (0.2 mg/kg every two weeks; 0.1 mg/kg weekly and; 0.2 mg/kg weekly), the other trial evaluated two further doses to the dosage schedules: 0.4 mg/kg every week and every other week. Both trials failed to show significant differences with various dosing schedules on globotriaosylceramide levels. No significant differences were found among the schedules for the primary efficacy outcome of self-assessed health state, or for pain scores.One trial comparing agalsidase alfa to agalsidase beta showed no significant difference for any adverse events such as dyspnoea and hypertension.The methodological quality of the included trials was generally unclear for the random sequence generation and allocation concealment. AUTHORS' CONCLUSIONS: Trials comparing enzyme replacement therapy to placebo show significant improvement with enzyme replacement therapy in regard to microvascular endothelial deposits of globotriaosylceramide and in pain-related quality of life. There is, however, no evidence identifying if the alfa or beta form is superior or the optimal dose or frequency of enzyme replacement therapy. With regards to safety, adverse events (i.e., rigors, fever) were more significant in the agalsidase beta as compared to placebo. The long-term influence of enzyme replacement therapy on risk of morbidity and mortality related to Anderson-Fabry disease remains to be established. This review highlights the need for continued research into the use of enzyme replacement therapy for Anderson-Fabry disease.


Asunto(s)
Terapia de Reemplazo Enzimático/métodos , Enfermedad de Fabry/tratamiento farmacológico , Isoenzimas/administración & dosificación , alfa-Galactosidasa/administración & dosificación , Enfermedad de Fabry/enzimología , Femenino , Humanos , Masculino , Dimensión del Dolor , Ensayos Clínicos Controlados Aleatorios como Asunto , Proteínas Recombinantes , Factores de Tiempo , Trihexosilceramidas/análisis , Trihexosilceramidas/sangre
3.
Clin Oral Investig ; 20(4): 815-9, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26319976

RESUMEN

OBJECTIVES: The development of endodontic sealers based on natural resins seems to be promising, given their improved biological properties. This study evaluated the cytotoxic and genotoxic effects of two experimental root canal sealers, based on extracts from Copaifera multijuga and Ricinus communis (castor oil polymer), comparing them to synthetic resin-based sealers: a single methacrylate-based, a multi-methacrylate-based, and an epoxy resin-based sealers. MATERIALS AND METHODS: Sealers were prepared, set, and exposed to cell culture medium for 24 h at 37 °C with CO2. V79 cells were exposed to serial dilutions of the extracts of each sealer for 24 h. Cell viability was measured by the MTT assay and genotoxicity was assessed by the formation of micronuclei. RESULTS: The single methacrylate-based sealer had the most cytotoxic effects, with significant reduction in cell viability in all dilutions of the extract. The castor oil polymer-based sealer was, on the other hand, the most biocompatible sealer, with no cytotoxic effects at any concentration. All tested sealers were not genotoxic, excepting the single methacrylate-based sealer. CONCLUSIONS: The tested natural resin-based sealers presented low cytotoxic and no genotoxic effects on cell cultures. CLINICAL RELEVANCE: These results may suggest a good alternative to develop new endodontic sealers, in order to achieve better biological response and healing, when compared to commercially available sealers.


Asunto(s)
Daño del ADN , Metacrilatos/toxicidad , Materiales de Obturación del Conducto Radicular/toxicidad , Resinas Epoxi , Humanos , Resinas Sintéticas
4.
Gen Dent ; 60(6): e393-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23220318

RESUMEN

Root perforations may lead to a loss of integrity in the root and periodontium, violations of the biologic periodontal distance, and injuries to periodontal tissue. This study sought to analyze the effect of root canal biomechanical preparation on the microhardness and the marginal sealing ability of different materials used to treat root perforations. Standard root perforations were performed in 96 bovine incisors. The teeth were divided into four groups (n = 24), based on the material used to treat those teeth: Mineral trioxide aggregate (MTA) (Group 1), MTA protected with cyanoacrylate (Group 2), MTA protected with glass ionomer (GI) cement (Group 3), and castor oil bean (COB) cement (Group 4). After root perforations were closed, the root canals were prepared biomechanically and teeth were sectioned longitudinally. Microleakage and microhardness of sealed perforations were assessed; microleakage data were submitted to analysis of variance (ANOVA) testing, while microhardness data were submitted to Dunnet and Tukey tests (p < 0.05). Group 4 reported the lowest amount of microleakage (0.65 mm), followed by Group 3 (1.02 mm), Group 1 (1.14 mm), and Group 2 (1.30 mm); however, no difference was detected among the groups. Groups 1-3 demonstrated significantly higher microhardness values compared to COB. It was concluded that the chemical and mechanical agents used during root canal preparation did not affect the sealing procedures. Administering surface protection to MTA did not improve microhardness or sealing.


Asunto(s)
Recubrimiento Dental Adhesivo , Cavidad Pulpar/lesiones , Materiales de Obturación del Conducto Radicular/química , Compuestos de Aluminio/química , Compuestos de Aluminio/uso terapéutico , Animales , Fenómenos Biomecánicos , Compuestos de Calcio/química , Compuestos de Calcio/uso terapéutico , Aceite de Ricino/química , Aceite de Ricino/uso terapéutico , Bovinos , Cianoacrilatos/química , Cianoacrilatos/uso terapéutico , Cementos Dentales/química , Cementos Dentales/uso terapéutico , Filtración Dental/clasificación , Combinación de Medicamentos , Colorantes Fluorescentes , Cementos de Ionómero Vítreo/química , Cementos de Ionómero Vítreo/uso terapéutico , Dureza , Humedad , Ensayo de Materiales , Óxidos/química , Óxidos/uso terapéutico , Rodaminas , Materiales de Obturación del Conducto Radicular/uso terapéutico , Preparación del Conducto Radicular/métodos , Silicatos/química , Silicatos/uso terapéutico , Propiedades de Superficie , Temperatura , Factores de Tiempo
5.
J Funct Biomater ; 11(2)2020 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-32560139

RESUMEN

Titanium nitride (TiN) and silicon carbide (SiC) adhesion properties to biofilm and the proliferation of human osteoblasts were studied. Quaternized titanium nitride (QTiN) was produced by converting the surface nitrogen on TiN to a positive charge through a quaternization process to further improve the antibacterial efficiency. The SiC required a nitridation within the plasma chamber of the surface layer before quaternization could be carried out to produce quaternized SiC (QSiC). The antimicrobial activity was evaluated on the reference strains of Porphyromonas gingivalis for 4 h by fluorescence microscopy using a live/dead viability kit. All the coatings exhibited a lower biofilm coverage compared to the uncoated samples (Ti-85.2%; TiN-24.22%; QTiN-11.4%; SiC-9.1%; QSiC-9.74%). Scanning Electron Microscope (SEM) images confirmed the reduction in P. gingivalis bacteria on the SiC and TiN-coated groups. After 24 h of osteoblast cultivation on the samples, the cell adhesion was observed on all the coated and uncoated groups. Fluorescence images demonstrated that the osteoblast cells adhered and proliferated on the surfaces. TiN and SiC coatings can inhibit the attachment of Porphyromonas gingivalis and promote osteoblast adhesion on the titanium used for implants. These coatings may possess the ability to prevent the development of peri-implantitis and stimulate osteointegration.

6.
ChemistrySelect ; 4(31): 9185-9189, 2019 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-32149184

RESUMEN

The formation and characterization of positively surface charged TiN surfaces were investigated for improving dental implant survival. Surface nitrogen atoms of a traditional TiN implant were converted to a positive charge by a quaternization reaction which greatly increased the antibacterial efficiency. Ti, TiN, and quaternized TiN samples were incubated with human patient subgingival bacteria for 4 hours at 37°C in an anaerobic environment with an approximate 40% reduction in counts on the quaternized surface over traditional Ti and TiN. The samples were challenged with Streptococcus Mutans and fluorescent imaging confirmed significant reduction in the quaternized TiN over the traditional Ti and TiN. Contact angle measurement and X-Ray Photoelectron Spectroscopy (XPS) were utilized to confirm the surface chemistry changes. The XPS results found the charged quaternized nitrogen peak at 399.75 eV that is unique to the quaternized sample.

7.
Carbohydr Polym ; 197: 47-56, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-30007637

RESUMEN

Processing stable polysaccharide membranes with suitable mechanical properties has been challenging for applications in wound healing and tissue engineering. Here we expand the characterization of pectin/chitosan (PT/CS) membranes (without covalent crosslinking), which we recently reported. Membranes containing pectin (PT) excess were formed, and PT/CS ratio can be tuned to enhance the mechanical strength, and to modulate hydrophilicity and cytocompatibility. The surface wettability and swelling properties of the polyelectrolyte complexes (PECs) played an important role to promote the attachment of stem cells. These PECs membranes have ultimate tensile strength similar to that of human skin, which is on the order of ten times higher than similar previously reported polysaccharide materials. We show for the first time that these new PT/CS membranes may promote anchorage, adhesion and support human stem cell growth, making them candidate materials for tissue engineering purposes.


Asunto(s)
Quitosano/farmacología , Pectinas/farmacología , Células Madre/citología , Adhesión Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Quitosano/química , Humanos , Tamaño de la Partícula , Pectinas/química , Espectroscopía de Fotoelectrones , Estrés Mecánico , Propiedades de Superficie , Ingeniería de Tejidos , Humectabilidad
8.
J Colloid Interface Sci ; 525: 21-30, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29680300

RESUMEN

Poly(ε-caprolactone) (PCL) is a hydrophobic and cytocompatible aliphatic polyester that has been used to produce PCL-based nanofibrous for both wound healing and tissue repair. However, the high hydrophobicity and low water adsorptive have been challenges for developing PCL-based materials for use in tissue engineering field. Here, we report a new polymer (a hydrophilic amino-functionalized tannin (TN)) that is associated with PCL for developing PCL-TN blends at different PCL:TN weight ratios (100:0, 95:5, 85:15 and 78:22). PCL:TN ratio may be tuned to modulate hydrophilicity and cytocompatibility of the nanofibers. The neutralization step and surface wettability played an important role in the attachment of human adipose-derived stem cells (ADSC cells) on PCL-TN membranes. Also, fluorescence images confirmed great proliferation of ADSC cells on the PCL-TN electrospun surfaces. Yet, neutralized PCL-TN nanofibers promoted bactericidal activity against Pseudomonas aeruginosa. These membranes have potential to be used as scaffolds for tissue engineering purposes.

9.
J Endod ; 33(4): 422-6, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17368331

RESUMEN

The aim of this study was to evaluate the number and the diameter of dentin tubules in root canals, in the cervical, middle, and apical thirds, of human and bovine teeth. Twenty-four single-rooted, human premolars were divided into four groups (n = 6): GH1, 10 to 15 years; GH2, 16 to 30 years; GH3, 31 to 45 years; and GH4, 46 to 80 years; and 24 bovine incisors were divided into four groups (n = 6): GB1, central; GB2, lateral first; GB3, lateral second; and GB4, lateral third. The crowns were removed from the specimens, which were then debrided, sectioned longitudinally in the vestibular-lingual direction, and submitted to ultrasonic cleaning. Scanning electron microscopic evaluations were made with 1,000x and 5,000x magnification. According to the root thirds, statistically significant differences were found both for the number and the diameter of dentin tubules, with the cervical third presenting the highest mean values for both specimen types. As regards the number of dentin tubules, it was observed that the bovine specimens presented a significantly higher mean value than the human specimens; this difference was not observed when the diameters of the two types were compared.


Asunto(s)
Cavidad Pulpar/ultraestructura , Dentina/ultraestructura , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Diente Premolar/ultraestructura , Bovinos , Niño , Humanos , Incisivo/ultraestructura , Microscopía Electrónica de Rastreo , Persona de Mediana Edad , Modelos Animales , Fotomicrografía , Preparación del Conducto Radicular , Ápice del Diente/ultraestructura
10.
J Mech Behav Biomed Mater ; 62: 10-23, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27161958

RESUMEN

This paper investigates the microstructure and the mechanical properties of ß-tricalcium phosphate (ß-TCP) three-dimensional (3D) porous materials reinforced with 45S5 bioactive glass (BG). ß-TCP and ß-TCP/x%-BG scaffolds with interconnected pores networks, suitable for bone regeneration, were fabricated by gel-casting method. Mechanical properties, porosity, and morphological characteristics were evaluated by compressive strength test, scanning electron microscopy (SEM) and X-ray microtomography analysis, whereas the structures were fully explored by XRD, and Raman spectroscopy. To the best of our knowledge, this is the first time where the mechanism for understanding the effect of bioglass on the mechanical properties and microstruture of ß-TCP/45S5-BG scaffolds has been systematically studied. The findings showed that ionic product lixiviated from 45S5 bioactive glass, rich in silicon species and sodium ion, catalyzes a phase transition from ß-TCP to Si-TCP by replacement of phosphorus for silicon and contributes to the improvement of scaffolds mechanical properties. The compressive strength of ß-TCP/5%-BG and ß-TCP/7.5%-BG was improved around 200% in comparison to pure ß-TCP. Osteoblast-like cells (MG 63) were exposed to the materials for 24h through the use of medium conditioned by ß-tricalcium phosphate/bioactive glass. Cell viability was measured by MTT assay in the cells and the data obtained were submitted to ANOVA, Tukey׳s multiple comparison (p<0.05). The ß-TCP/7.5-BG promoted an increase of cell proliferation. The results suggest that compositions and processing method studied may provide appropriate materials for tissue engineering.


Asunto(s)
Materiales Biocompatibles/química , Fosfatos de Calcio/química , Cerámica/química , Andamios del Tejido , Porosidad , Ingeniería de Tejidos
11.
J Endod ; 38(4): 495-500, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22414836

RESUMEN

INTRODUCTION: MTA has good biological properties, and it is a mineralization-inducing material with different indications in endodontics. Initially this material was not recommended as root canal sealer. However, a resin sealer based on mineral trioxide aggregate (MTA Fillapex) was recently released with this indication. Because MTA is in contact with the periodontal tissues, bone, and pulp, it is important to know its cytotoxic and genotoxic effects. The purpose of this study was to evaluate the cytotoxicity and genotoxicity of MTA canal sealer (Fillapex) compared with white MTA cement and AH Plus. METHODS: Chinese hamster fibroblasts (V79) were placed in contact with different dilutions of culture media previously exposed to such materials. Cytotoxicity was evaluated by methol-thiazol-diphenyl tetrazolium assay in spectrophotometer to check the viability rate and cell survival. The genotoxicity was accessed by the micronucleus formation assay. Cell survival rate and micronuclei number were assessed before and after exposure to cement extracts, and the results were statistically analyzed by Kruskal-Wallis and Dunn tests (P < .05). RESULTS: The results showed that the cell viability remained above 50% in white MTA group for all dilutions. AH Plus induced an intermediate cytotoxicity in a dilution-dependent manner, followed by Fillapex MTA. CONCLUSIONS: White MTA group was the less cytotoxic material in this study. Both AH Plus and Fillapex MTA sealer showed the lowest cell viability rates and caused an increased micronucleus formation when compared with control untreated group.


Asunto(s)
Compuestos de Aluminio/toxicidad , Materiales Biocompatibles/toxicidad , Compuestos de Calcio/toxicidad , Fibroblastos/efectos de los fármacos , Óxidos/toxicidad , Materiales de Obturación del Conducto Radicular/toxicidad , Silicatos/toxicidad , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Colorantes , Cricetinae , Citotoxinas/toxicidad , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Resinas Epoxi/toxicidad , Ensayo de Materiales , Pruebas de Micronúcleos , Mutágenos/toxicidad , Espectrofotometría , Sales de Tetrazolio , Tiazoles , Factores de Tiempo
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