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1.
Compend Contin Educ Dent ; 41(3): e1-e9, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32125165

RESUMEN

More than 2,000 dental implant options are estimated to be available for any given clinical situation. Because many implants have claims that are substantiated mainly on the basis of in vitro studies, it is prudent for clinicians to understand the interpretation of such studies and possible clinical relevance. In vitro tests can be segregated as surface analysis tests and mechanical assessment tests. With a wide variation of methodologies used and results achieved by different implant manufacturers, practitioners may find it difficult to judge the clinical significance of in vitro tests. This article provides an overview, including limitations, of the in vitro implant analysis tests implant companies routinely perform, ranging from older methods involving mechanical testing and surface microscopy to more recent tests such as atomic force microscopy (AFM) studies and gene expression tests, to assist clinicians when choosing an implant system. Having identified the limitations of in vitro testing methods, the current evidence indicates that scanning electron microscopy may be useful in providing insight on the role of implant surface topography. AFM, single cell tests, 3D imaging, and gene expression tests could be useful for assessment of cellular and physio-biochemical properties. 3D finite element analysis may help in the evaluation of mechanical properties of dental implants. Clinicians are encouraged to correlate the findings of in vitro tests with robust animal histologic studies and well-designed, high-quality clinical research to ascertain optimum clinical results.


Asunto(s)
Implantes Dentales , Animales , Técnicas In Vitro , Microscopía Electrónica de Rastreo , Propiedades de Superficie , Titanio
2.
Braz Oral Res ; 34: e018, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32187304

RESUMEN

The objective of this study was to evaluate the influence of hydrofluoric acid (HF) concentration, etching time, and application of phosphoric acid (PA) followed by neutralization with sodium bicarbonate on the bond strength between a feldspar ceramic and resin cement. Thus, 80 blocks (10 x 12 x 2 mm) of glass ceramic (VM - Vita Mark II - Vita Zahnfabrik) were made and randomly assigned to eight groups (n = 10) according to the factors: HF concentration (5 and 10%), etching time (60 and 120 s), and use of phosphoric acid (PA) (with and without). According to the experimental group, 37% PA (Condac, FGM) was applied after HF etching for 60s. Afterwards, samples were immersed in sodium bicarbonate for 1 min then in an ultrasonic bath in distilled water (5 min) for cleaning. After surface bonding treatment, cylinders (Ø = 2 mm; h = 2 mm) of dual resin cement (AllCem / FGM) were made in the center of each block. The samples were then stored in water (37ºC) for 90 days and submitted to the shear bond test (50 KgF, 1 mm/min). Failure analysis was performed by stereomicroscope and scanning electron microscopy. Data (MPa) were analyzed with 3-way ANOVA and Tukey's test. Only the factor "HF concentration" was significant (p = 0.02). Most failures were of cohesive in ceramic (40%) and mixed types (42.5%). The 10% HF resulted in higher shear bond strength value than the 5% HF. Surface cleaning with phosphoric acid followed by sodium bicarbonate and HF time (60 or 120 seconds) did not influence the resin bond strength to feldspar ceramic.


Asunto(s)
Silicatos de Aluminio/química , Recubrimiento Dental Adhesivo/métodos , Ácido Fluorhídrico/química , Ácidos Fosfóricos/química , Compuestos de Potasio/química , Análisis de Varianza , Porcelana Dental/química , Ensayo de Materiales , Metacrilatos/química , Microscopía Electrónica de Rastreo , Valores de Referencia , Reproducibilidad de los Resultados , Cementos de Resina/química , Resistencia al Corte/efectos de los fármacos , Silanos/química , Propiedades de Superficie , Factores de Tiempo
3.
J Indian Soc Pedod Prev Dent ; 38(1): 56-63, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32174630

RESUMEN

Objective: The quest for ideal pulp capping materials has given rise to the development of newer materials such as light cure mineral trioxide aggregate (MTA). The bond strength of the pulp capping materials with overlying restoration is one among the several factors that are critical for the success of vital pulp therapy. Hence, we conducted this study to evaluate and compare the shear bond strength (SBS) of light cure MTA and light cure calcium hydroxide with nanofilled composite. Materials and Methods: Thirty acrylic blocks each with a central hole were prepared to uniform dimensions and randomly distributed into two equal groups. In Group I, light cure MTA, and in Group II, light cure calcium hydroxide was used as pulp capping materials. After the application of adhesive system, nanofilled composites were applied onto the pulp capping material using a cylindrical plastic matrix. The SBS was tested on a universal testing machine (Instrom 3366, UK) at a crosshead speed of 0.5 mm/min. The samples were examined under stereomicroscope and scanning electron microscope to analyze different modes of failure. Results: The results were statistically analyzed using independent sample t-test. Light cure MTA attained the mean SBS of 6.54 MPa and light cure calcium hydroxide attained the mean SBS of 6.56 MPa. There was no significant difference statistically in SBS of both the materials (P < 0.05). The modes of failure were predominantly mixed failure followed by cohesive failure within the restorative material in both Group I and II. Conclusion: The results of the study suggest that the SBS of light cure MTA and light cure calcium hydroxide is comparable. The modes of failure analyzed in both light cure MTA and light cure calcium hydroxide are not significantly different statistically. Hence, both materials can be successfully used as pulp capping material with nanofilled composite.


Asunto(s)
Hidróxido de Calcio , Recubrimiento Dental Adhesivo , Compuestos de Aluminio , Compuestos de Calcio , Resinas Compuestas , Recubrimiento de la Pulpa Dental , Combinación de Medicamentos , Microscopía Electrónica de Rastreo , Óxidos , Silicatos
4.
J Indian Soc Pedod Prev Dent ; 38(1): 64-70, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32174631

RESUMEN

Introduction: The chemomechanical preparation of root canal dentin with hand or rotary instruments creates debris and a smear layer. Root canal preparation (RCP) along with irrigants is not effective in cleaning apical portions, and hence, different laser activation systems were used for better cleaning in the apical third. Aim: The aim of this study is to compare the efficacy of erbium: yttrium-aluminum-garnet (Er:YAG) and diode laser irradiation in smear layer removal and dentin permeability after biomechanical preparation using scanning electron microscopic investigation. Material and Methods: Thirty sound single-rooted human teeth were distributed randomly and equally into three groups (n = 10 each) based upon the type of laser irradiation after RCP: Group I (control group) - RCP with ProTaper rotary system using the standard irrigating protocol; Group II - RCP with ProTaper rotary system using the standard irrigating protocol followed by diode laser irradiation; and Group III - RCP with ProTaper rotary system using the standard irrigating protocol followed by Er:YAG laser irradiation. After root sectioning, specimens were dehydrated, then gold plated and observed using a scanning electron microscopy. Then, the smear layer scores were recorded and performed using the statistical analysis. Results: Smear layer removal efficacy of Er:YAG laser was more at coronal, middle, and apical third when compared to Group I and Group II. Debris removal score of Group III (Er:YAG) was better than Group I (17% ethylenediaminetetraacetic acid) and Group II (diode). Conclusion: Er:YAG laser-activated RCP was comparatively efficient in cleaning the smear layer and dentinal tubules opening.


Asunto(s)
Capa de Barro Dentinario , Aluminio , Cavidad Pulpar , Dentina , Permeabilidad de la Dentina , Erbio , Humanos , Láseres de Semiconductores , Microscopía Electrónica de Rastreo , Irrigantes del Conducto Radicular , Preparación del Conducto Radicular , Itrio
5.
J Biol Regul Homeost Agents ; 34(1 Suppl. 1): 49-54, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32064835

RESUMEN

Though the literature reports a well-documented scientific evidence of the performance of modern adhesive systems on normal dentin, few researches are available on the interaction between adhesives and compromised dentin. In this study, the authors analyzed the microscopic structural aspects of the adhesive interface on two common altered dentin substrates: dentin contaminated by metallic oxides and caries affected dentin. Thirty teeth were selected and divided in three groups of ten teeth according to the different dentin substrate they had: (A) normal dentin, (B) caries-affected dentin and (C) dentin contaminated by metallic oxides. The experimental cavity preparation was realised exposing in each sample, portion of pathologic dentin and portion of sound dentin as control. Each cavity was restored with micro-hybrid composite, with total etching and a two-step adhesive system. Each sample was sectioned in two halves analysed with two SEM micro-morphological methods: direct observation and decalcification. SEM investigations were able to show the difference in thickness and morphology of the adhesive interface with the two different dentin variables. Caries affected dentin determined the formation of less distinctive resin tags with few micro-tags. Discoloured dentin showed a poor infiltration with few resin tags probably due to alterations in the tubular structures. The micro-morphological variability of dentin substrate influences the clinical efficacy of bonding restorations determining significant differences in the qualitative and quantitative aspects of resin tags.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Dentina , Microscopía Electrónica de Rastreo , Grabado Ácido Dental , Resinas Compuestas , Humanos , Cementos de Resina
6.
Rev Soc Bras Med Trop ; 53: e20190214, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32049200

RESUMEN

INTRODUCTION: The aim of this study was to evaluate some virulence factors in Candida albicans isolates from patients with onychomycosis and determine the correlation between these factors and the antifungal resistance profile. METHODS: Seventy species of C. albicans were confirmed using polymerase chain reaction amplification of the HWP1 gene. According to the Clinical & Laboratory Standards Institute guidelines, the susceptibility profile of four antifungal agents was investigated, and the production of aspartyl protease, phospholipase, haemolysin, and biofilm was determined. The correlation between these profiles was also investigated. RESULTS: The isolates indicated different levels of resistance and production of virulence factors. Significant correlations were observed between the minimum inhibitory concentration (MIC) of fluconazole/itraconazole and biofilm production, between phospholipase production and fluconazole/itraconazole MIC, and between fluconazole MIC and hemolytic activity in C. albicans isolates. The results also showed significant correlations between phospholipase activity and biofilm production. CONCLUSIONS: Our findings will contribute to a better understanding of the pathogenesis of C. albicans and characterize the relationship between virulence factors and antifungal resistance, which may suggest new therapeutic strategies considering the possible involvement of the virulence mechanism in the effectiveness of treatment.


Asunto(s)
Antifúngicos/farmacología , Candida albicans/patogenicidad , Uñas/microbiología , Onicomicosis/microbiología , Factores de Virulencia , Proteasas de Ácido Aspártico/biosíntesis , Biopelículas/crecimiento & desarrollo , Candida albicans/efectos de los fármacos , Candida albicans/ultraestructura , Farmacorresistencia Fúngica , Hemólisis , Humanos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Fosfolipasas/biosíntesis , Reacción en Cadena de la Polimerasa
7.
Chem Biol Interact ; 319: 109019, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32092302

RESUMEN

The inhibition of the enzyme acetylcholinesterase (AChE) is a frequently used therapeutic option to treat Alzheimer's disease (AD). By decreasing the levels of acetylcholine degradation in the synaptic space, some cognitive functions of patients suffering from this disease are significantly improved. Rivastigmine is one of the most widely used AChE inhibitors. The objective of this work was to determine the effects of this drug on human erythrocytes, which have a type of AChE in the cell membrane. To that end, human erythrocytes and molecular models of its membrane constituted by dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE) were used. They correspond to classes of phospholipids present in the outer and inner monolayers of the human erythrocyte membrane, respectively. The experimental results obtained by X-ray diffraction and differential scanning calorimetry (DSC) indicated that rivastigmine molecules were able to interact with both phospholipids. Fluorescence spectroscopy results showed that rivastigmine produce a slight change in the acyl chain packing order and a weak displacement of the water molecules of the hydrophobic-hydrophilic membrane interface. On the other hand, observations by scanning electron microscopy (SEM) showed that the drug changed the normal biconcave shape of erythrocytes in stomatocytes (cup-shaped cells) and echinocytes (speculated shaped).


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/farmacología , Eritrocitos/efectos de los fármacos , Rivastigmina/farmacología , Acetilcolinesterasa/metabolismo , Enfermedad de Alzheimer/metabolismo , Rastreo Diferencial de Calorimetría/métodos , Forma de la Célula/efectos de los fármacos , Dimiristoilfosfatidilcolina/metabolismo , Membrana Eritrocítica/efectos de los fármacos , Membrana Eritrocítica/metabolismo , Eritrocitos/metabolismo , Humanos , Microscopía Electrónica de Rastreo/métodos , Modelos Moleculares , Fosfatidiletanolaminas/metabolismo , Fosfolípidos/metabolismo , Espectrometría de Fluorescencia/métodos , Difracción de Rayos X/métodos
8.
Braz Oral Res ; 34: e004, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32022223

RESUMEN

The aim of this study was to analyze the structural, morphological and mechanical properties of two different lithium disilicate glass-reinforced ceramics for CAD-CAM systems (IPS e.max CAD and Rosetta SM). Five methodologies were used for both ceramics: microstructure (n = 2) was analyzed using x-ray diffraction (XRD); morphological properties (n = 2) were analyzed by scanning electron microscopy (SEM), with and without hydrofluoric etching; porosity (n = 3) was assessed using 3D micro-computed tomography (micro-CT); flexural strength was measured (n =1 0) using the three-point bending test; and bond strength was determined with self-adhesive resin cement (n = 10), using a microshear bond test. After performing all the tests, the data were analyzed using t-Student test and two-way ANOVA. All the tests used a significance level of α = 0.05. High peak positions corresponding to standard lithium metasilicate and lithium disilicate with similar intensities were observed for both ceramics in the XRD analysis. Morphological analysis showed that the crystalline structure of the two ceramics studied showed no statistical difference after acid etching. Additionally, no significant differences were recorded in the number or size of the pores for the ceramics evaluated. Moreover, no differences in flexural strength were found for the ceramic materials tested, or in the bond strength to ceramic substrates for the resin cements. Based on the study results, no significant differences were found between the two CAD-CAM lithium disilicate glass-reinforced ceramics tested, since they presented similar crystalline structures with comparable intensities, and similar total porosity, flexural strength and bond strength.


Asunto(s)
Cerámica/química , Diseño Asistido por Computador , Porcelana Dental/química , Vidrio/química , Análisis de Varianza , Recubrimiento Dental Adhesivo/métodos , Resistencia Flexional , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Porosidad , Valores de Referencia , Reproducibilidad de los Resultados , Cementos de Resina/química , Resistencia al Corte , Propiedades de Superficie , Difracción de Rayos X
9.
Braz Oral Res ; 34: e005, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32022224

RESUMEN

The purpose of this study was to evaluate the effect of ionizing radiation from high energy X-ray on fluoride release, surface roughness, flexural strength, and surface chemical composition of the materials. The study groups comprised five different restorative materials: Beautifil II, GCP Glass Fill, Amalgomer CR, Zirconomer, and Fuji IX GP. Twenty disk-shaped specimens (8x2 mm) for fluoride release and 20 bar-shaped specimens (25 x 2x 2 mm) for flexural strength were prepared from each material. Each material group was divided into two subgroups: irradiated (IR) and non-irradiated (Non-IR). The specimens from IR groups were irradiated with 1.8 Gy/day for 39 days (total IR = 70.2 Gy). The amount of fluoride released into deionized water was measured using a fluoride ion-selective electrode and ion analyzer after 24 hours and on days 2, 3, 7, 15, 21, 28, 35, and 39 (n = 10). The flexural strength was evaluated using the three-point bending test (n = 10). After the period of measurement of fluoride release, seven specimens (n = 7) from each group were randomly selected to evaluate surface roughness using AFM and one specimen was randomly selected for the SEM and EDS analyses. Data were analyzed with two-way ANOVA and Tukey tests (p = 0.05). The irradiation significantly increased fluoride release and surface roughness for Amalgomer CR and Zirconomer groups (p < 0.05). No significant change in flexural strength of the materials was observed after irradiation (p > 0.05). The ionizing radiation altered the amount of fluoride release and surface roughness of only Amalgomer CR and Zirconomer. The effect could be related to the chemical compositions of materials.


Asunto(s)
Apatitas/efectos de la radiación , Bisfenol A Glicidil Metacrilato/efectos de la radiación , Resinas Compuestas/efectos de la radiación , Fluoruros/química , Cementos de Ionómero Vitreo/efectos de la radiación , Radiación Ionizante , Circonio/efectos de la radiación , Análisis de Varianza , Apatitas/química , Bisfenol A Glicidil Metacrilato/química , Resinas Compuestas/química , Resistencia Flexional , Cementos de Ionómero Vitreo/química , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Valores de Referencia , Reproducibilidad de los Resultados , Espectrometría por Rayos X , Estadísticas no Paramétricas , Propiedades de Superficie/efectos de la radiación , Factores de Tiempo , Circonio/química
10.
Int J Prosthodont ; 33(2): 217-223, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32069347

RESUMEN

PURPOSE: To evaluate the surface roughness values of zirconium oxide samples that were gradually polished using a commercially available polishing system and polishing paste. MATERIALS AND METHODS: A total of 50 rectangular specimens of predetermined size (10 × 10 × 3 mm) were sintered from zirconium oxide. Samples were randomly assigned to one of five groups (n = 10 each): control, coarse (Co), fine (F), super fine (SF), or polishing paste (PP). In the control group, no polishing was done; in the Co group, a coarse polisher was used; and the specimens in the remaining three groups underwent additional processing with a fine rubber abrasive. For SF and PP samples, subsequent treatment with a super fine polisher was applied. Finally, for the PP group, a goat-hair brush with diamond polishing paste was used. An optical profilometer was used to evaluate roughness average (Ra) in micrometers (µm). ANOVA and Games-Howell post hoc tests were utilized to detect differences between groups. The significance level was set to α = .05. RESULTS: Surface roughness gradually decreased with further polishing throughout the groups: control Ra = 0.525 ± 0.099 µm; Co Ra = 0.252 ± 0.038 µm; F Ra = 0.196 ± 0.035 µm; SF Ra = 0.114 ± 0.031 µm; and PP Ra = 0.054 ± 0.020 µm. Statistically significant differences were detected among all groups (P < .05). CONCLUSION: A surface roughness of 0.054 µm can be achieved if a full zirconia polishing protocol is used. Zirconium oxide can be polished to various surface roughnesses using commercially available polishing products.


Asunto(s)
Pulido Dental , Circonio , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Propiedades de Superficie
11.
Zoolog Sci ; 37(1): 14-23, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32068370

RESUMEN

Olfaction plays an important role in a fish's life. Its value may differ at different developmental stages, depending on the feeding style of the species. The goal of the present study was to investigate the olfactory organ of a species that feeds mainly on algae- the bushymouth catfish, Ancistrus dolichopterus-at developmental stages from olfactory placode to the definitive olfactory chamber. For this study, we used light and electron (scanning) microscopy. The topography of the olfactory placode of A. dolichopterus is typical for teleostei. Formation of olfactory pit takes place at the same time as rostral elevation formation. Rostral elevation participates in the formation of the nasal bridge and anterior tubular nostril. It was found out that the anlage of olfactory rosette in A. dolichopterus arises earlier than in most teleostei. However, the number of lamellae does not increase until switching to exogenous feeding. We suppose that the early development of olfactory organ is necessary for intraspecific communication, not just for finding food.


Asunto(s)
Bagres/crecimiento & desarrollo , Morfogénesis , Vías Olfatorias/crecimiento & desarrollo , Animales , Bagres/anatomía & histología , Conducta Alimentaria , Microscopía Electrónica de Rastreo , Vías Olfatorias/ultraestructura
12.
Zoolog Sci ; 37(1): 79-90, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32068377

RESUMEN

We describe here a new pterobranch, Cephalodiscus planitectus sp. nov. This pterobranch was collected from rocky slopes, at 100-300 m depth, off Jogashima Island, Sagami Bay, Japan. The tubaria of this new species have unique morphological features that differentiate it from known species. The tubaria are usually isolated from one another and have a completely flat and smooth surface that is devoid of erect features and projecting spines. Each has a simple, non-branched tubular cavity that is usually inhabited by a mature animal and its asexually budding offspring. The zooids have three pairs of tentaculated arms. A single bud is produced on the dorsal side of the stalk in adult zooids. In one instance, a live embryo was observed rotating at the bottom of a tubarium. Molecular phylogenetic analysis showed that C. planitectus is a sister group to all other Cephalodiscus species analyzed to date.


Asunto(s)
Invertebrados/anatomía & histología , Invertebrados/clasificación , Animales , Invertebrados/genética , Invertebrados/ultraestructura , Japón , Microscopía Electrónica de Rastreo , Filogenia , ARN Ribosómico 18S/genética , Especificidad de la Especie
13.
J Appl Oral Sci ; 28: e20190145, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32049132

RESUMEN

OBJECTIVE: Ultrasonic wave technology is widely used during dental treatments. We previously demonstrated that this method protects the gingival tissue. However, the physiological change on the gingival microvasculature caused by this method remains unclear. The aim of this study was to investigate the relationship between the morphological and physiological effects on gingival microcirculation when preparing teeth, using the conventional dental turbine or ultrasonic method. METHODOLOGY: The lower premolar teeth of beagle dogs were prepared along the gingival margin by using a dental turbine or ultrasonic wave instrument. Gingival vasculature changes were investigated using scanning electron microscopy for corrosion resin casts. Gingival blood flow at the preparation site was determined simultaneously by laser Doppler flowmetry. These assessments were performed immediately (Day 0), at 7 days and 30 days after tooth preparation. RESULTS: At day 0, in the turbine group, blood vessels were destroyed and some resin leaked. Furthermore, gingival blood flow at the site was significantly increased. In contrast, the ultrasonic group demonstrated nearly normal vasculature and gingival blood flow similar to the non-prepared group for 30 days after preparation. No significant alterations occurred in gingival circulation 30 days after either preparation; however, the turbine group revealed obvious morphological changes. CONCLUSIONS: Based on multiple approach analyses, this study demonstrated that ultrasonic waves are useful for microvascular protection in tooth preparation. Compared with a dental turbine, ultrasonic wave instruments caused minimal damage to gingival microcirculation. Tooth preparation using ultrasonic wave instruments could be valuable for protecting periodontal tissue.


Asunto(s)
Encía/irrigación sanguínea , Microcirculación/fisiología , Preparación del Diente/instrumentación , Ondas Ultrasónicas , Animales , Protocolos Clínicos , Instrumentos Dentales , Perros , Femenino , Humanos , Flujometría por Láser-Doppler/métodos , Microscopía Electrónica de Rastreo , Reproducibilidad de los Resultados , Factores de Tiempo , Preparación del Diente/métodos
14.
J Appl Oral Sci ; 28: e20190156, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32049134

RESUMEN

OBJECTIVE: The present study aimed to investigate the participation of focal adhesion kinases (FAK) in interactions between osteoblastic cells and titanium (Ti) surfaces with three different topographies, namely, untreated (US), microstructured (MS), and nanostructured (NS). METHODOLOGY: Osteoblasts harvested from the calvarial bones of 3-day-old rats were cultured on US, MS and NS discs in the presence of PF-573228 (FAK inhibitor) to evaluate osteoblastic differentiation. After 24 h, we evaluated osteoblast morphology and vinculin expression, and on day 10, the following parameters: gene expression of osteoblastic markers and integrin signaling components, FAK protein expression and alkaline phosphatase (ALP) activity. A smooth surface, porosities at the microscale level, and nanocavities were observed in US, MS, and NS, respectively. RESULTS: FAK inhibition decreased the number of filopodia in cells grown on US and MS compared with that in NS. FAK inhibition decreased the gene expression of Alp, bone sialoprotein, osteocalcin, and ALP activity in cells grown on all evaluated surfaces. FAK inhibition did not affect the gene expression of Fak, integrin alpha 1 ( Itga1 ) and integrin beta 1 ( Itgb1 ) in cells grown on MS, increased the gene expression of Fak in cells grown on NS, and increased the gene expression of Itga1 and Itgb1 in cells grown on US and NS. Moreover, FAK protein expression decreased in cells cultured on US but increased in cells cultured on MS and NS after FAK inhibition; no difference in the expression of vinculin was observed among cells grown on all surfaces. CONCLUSIONS: Our data demonstrate the relevance of FAK in the interactions between osteoblastic cells and Ti surfaces regardless of surface topography. Nanotopography positively regulated FAK expression and integrin signaling pathway components during osteoblast differentiation. In this context, the development of Ti surfaces with the ability to upregulate FAK activity could positively impact the process of implant osseointegration.


Asunto(s)
Proteína-Tirosina Quinasas de Adhesión Focal/antagonistas & inhibidores , Osteoblastos/efectos de los fármacos , Quinolonas/farmacología , Sulfonas/farmacología , Titanio/química , Animales , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Proteína-Tirosina Quinasas de Adhesión Focal/análisis , Proteína-Tirosina Quinasas de Adhesión Focal/química , Expresión Génica , Integrinas/análisis , Microscopía Electrónica de Rastreo , Oseointegración/efectos de los fármacos , Osteoblastos/fisiología , Quinolonas/química , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción de Señal , Sulfonas/química , Propiedades de Superficie
15.
J Photochem Photobiol B ; 204: 111769, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31954264

RESUMEN

The goal of this study was to investigate the protective effects of nanostructured lipid carriers (NLCs) and vitamin E loaded NLCs (Vit E-NLCs) on preventing hair damages and discoloration against UV radiation and thermal treatment. The NLCs and Vit E-NLCs were prepared using a high-pressure homogenization technique. At optimal conditions, they showed spherical particles with a mean particle size of ~140 nm and a polydispersity index of < 0.3. Up to 90% (w/w) vitamin E acetate incorporation efficacy was achieved. The protective efficacy of the model cream containing blank-NLCs (NLCs cream) or Vit E-NLCs (Vit E-NLCs cream) was investigated. Upon exposure to UV-light and heat, the FE-SEM images revealed that the hair treated with both NLCs creams showed a smoothness of hair surface similar to the virgin hair. In accordance with protein loss, they exhibited the least protein loss as compared to the hair treated with Vit-E cream, cream base and commercial products. The same trend was observed for the discoloration test, the hair treated with both NLCs creams demonstrated the lowest total color loss, as compared to other products. Comparing between two NLCs formulations, antioxidant Vit E-NLCs showed to promote the photoprotective effect against hair damage and discoloration slightly greater than blank NLCs, but it has no extra benefit for heat protection. Considered overall, the developed NLCs and Vit E-NLCs is a novel alternative for preventing hair damage and discoloration from daily UV and heat exposure.


Asunto(s)
Portadores de Fármacos/química , Cabello/efectos de los fármacos , Lípidos/química , Nanoestructuras/química , Rayos Ultravioleta , Animales , Color , Composición de Medicamentos , Cabello/efectos de la radiación , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Especies Reactivas de Oxígeno/metabolismo , Temperatura Ambiental , Vitamina E/química , Vitamina E/farmacología
16.
J Photochem Photobiol B ; 204: 111764, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31972451

RESUMEN

This study was to assess the impact on the cornea and eye blink activity of adapting rabbits to continuous lighting (CL) compared to a 14:10 light:dark cycle. Female New Zealand White rabbits (2 to 2.5 kg) were maintained under a light: dark (L:D) cycle or switched to continuous fluorescent lighting (CL) for an average of 17 +/- 2 days. Animal behaviour in their cages was manually recorded using an event marker and in vivo slitlamp biomicroscopy at 40× undertaken in mid-afternoon. Animals were then euthanized and the corneas prepared for scanning electron microscopy (SEM). From images taken at 500× from the central region of the corneas, the number of exfoliating (desquamating) cells and the relative number of different cells with light, medium or dark reflexes were assessed for the corneal epithelial surface, while the number of cells/unit area were assessed for both corneal epithelium and endothelium. Exposure to continuous lighting was associated with higher number of eye blink events (15.7 vs 8.2/15 min) and mild corneal surface alterations evident by biomicroscopy with higher numbers of intra-epithelial 'granules' (32 +/- 14 vs. 4 +/- 3/sq. mm). SEM revealed low numbers of exfoliating cells on the corneal epithelial surface in all CL-adapted animals, but not in L:D controls. Trends were observed for there to be slightly higher numbers of epithelial cells/unit area, higher numbers of small light reflex cells and lower numbers of larger dark reflex cells in CL animals. The corneal endothelium showed no obvious adverse effects in CL-adapted animals but the percentage of 'hexagonal' cells was slightly higher compared to L:D controls. The results indicate that even a short period of exposure of laboratory-raised rabbits to constant lighting can be associated with mild adverse effects on the corneal epithelial surface.


Asunto(s)
Epitelio Anterior/efectos de la radiación , Iluminación , Animales , Parpadeo/efectos de la radiación , Recuento de Células , Endotelio/citología , Endotelio/patología , Endotelio/efectos de la radiación , Epitelio Anterior/citología , Epitelio Anterior/patología , Femenino , Microscopía Electrónica de Rastreo , Conejos
17.
J Parasitol ; 106(1): 56-70, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31995719

RESUMEN

Rhadinorhynchus hiansi Soota and Bhattacharya, 1981 , has remained unknown since its original incomplete description from 2 male specimens collected from the flat needlefish Ablennes hians Valenciennes (Belonidae) off Trivandrum, Kerala, India. Recent collections of fishes along the Pacific coast of Vietnam in 2016 and 2017 produced many specimens of the same species from the striped bonito Sarda orientalis Temminck and Schlegel (Scombridae) off the southern Pacific coast of Vietnam at Nha Trang. We describe females for the first time, assign a female allotype status, and provide an expanded description of males from a larger collection completing missing information on hooks and hook roots, receptacle, lemnisci, cement glands, Saefftigen's pouch, and trunk spines. Specimens of R. hiansi characteristically have no dorsal spines in the posterior field of trunk spines and a long proboscis with 36-48 dorso-ventrally differentiated proboscis hooks per row becoming progressively smaller posteriorly then increasing in size near the posterior end to a maximum at the posterior-most ring. Trunk, testes, and lemnisci in our specimens were considerably larger than those reported in the original description, but the proboscis was relatively smaller. The females had long reproductive system and corrugated elliptic eggs without polar prolongation of fertilization membrane. Energy Dispersive X-ray Analysis (EDXA) demonstrates high levels of calcium and phosphorus in large gallium cut hooks and high levels of sulfur in tip cuts of large and small hooks and in spines. This EDXA pattern is a characteristic fingerprint of R. hiansi. The molecular profile of R. hiansi is described from 18S rDNA and COI genes, and phylogenetic relationships with most closely related species are discussed.


Asunto(s)
Acantocéfalos/anatomía & histología , Acantocéfalos/genética , Beloniformes/parasitología , Enfermedades de los Peces/parasitología , Helmintiasis Animal/parasitología , Acantocéfalos/clasificación , Acantocéfalos/ultraestructura , Algoritmos , Animales , Teorema de Bayes , Femenino , Peces , Galio , Funciones de Verosimilitud , Masculino , Microscopía Electrónica de Rastreo/veterinaria , Océano Pacífico , Filogenia , Espectrometría por Rayos X/veterinaria , Vietnam
18.
Eur J Histochem ; 64(1)2020 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-31941265

RESUMEN

The seed morphology of three Pseudocereal Grains (PSCg), i.e. quinoa (Chenopodium quinoa Willd, Chenopodiaceae), buckwheat (Fagopyrum esculentum Moench, Polygonaceae) and amaranth (Amaranthus caudatus L., Amaranthaceae) was studied by light microscopy (LM) and Environmental Scanning Electron Microscopy coupled with Energy Dispersive Spectroscopy (ESEM-EDS). LM was used with visible light to evaluate either unstained sections or sections stained with Azan mixture and with fluorescent light. The aim of the study was to compare the architecture of the three seeds in order to connect their morphology with nutrient localization. The Azan staining allowed for the visualization of the seed coat, the embryo - with its shoot apical meristem - and the radicle cell layers, whereas the use of fluorescent microscopy identified the cells rich in phenolic compounds. Finally, the ESEM-EDS analysis revealed that the seed coat of the quinoa was thinner than that of amaranth or buckwheat. In all PSCg, starch granules appeared to be located in large polygonal cells, surrounded by a thin cell wall. Several globoids of proteins were observed in the embryo cells. In the radicle section, the vascular bundles of the procambium were evident, while Amaranth only showed a consistent layer of calcium crystals, located between the embryo and the perysperm. The morphological differences of the three PSCg were discussed in the context of their structural resistance to processing technologies which impact on nutritional value of derived foods.


Asunto(s)
Amaranthus/anatomía & histología , Chenopodium quinoa/anatomía & histología , Grano Comestible/anatomía & histología , Fagopyrum/anatomía & histología , Semillas/anatomía & histología , Amaranthus/embriología , Chenopodium quinoa/embriología , Grano Comestible/embriología , Fagopyrum/embriología , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Semillas/embriología
19.
World J Microbiol Biotechnol ; 36(2): 24, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31965331

RESUMEN

The study evaluated the antibacterial activity of chlorogenic acid (CA) against Salmonella Enteritidis S1, a foodborne pathogen in chilled fresh chicken. Its minimum inhibitory concentration for S. Enteritidis S1 was 2 mM. 1 MIC CA treatment reduced the viable count of S. Enteritidis S1 by 3 log cfu/g in chilled fresh chicken. Scanning electron microscopy examination indicated that CA induced the cell envelope damage of S. Enteritidis S1. Following this, 1-N-Phenylnaphthylamine assay and LPS content analysis indicated that CA induced the permeability of outer membrane (OM). Confocal laser scanning microscopy examination further demonstrated that CA acted on the inner membrane (IM). To support this, the release of intracellular protein and ATP after CA treatment was also observed. CA also suppressed the activities of malate dehydrogenase and succinate dehydrogenase, two main metabolic enzymes in TCA cycle and electron transport chain. Thus, damage of intracelluar and outer membranes as well as disruption of cell metabolism resulted in cell death eventually. The finding suggested that CA has the potential to be developed as a preservative to control S. Enteritidis associated foodborne diseases.


Asunto(s)
Antibacterianos/farmacología , Ácido Clorogénico/farmacología , Salmonella enteritidis/efectos de los fármacos , Animales , Proteínas Bacterianas/antagonistas & inhibidores , Membrana Celular/efectos de los fármacos , Pollos/microbiología , Recuento de Colonia Microbiana , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Malato Deshidrogenasa/antagonistas & inhibidores , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Microscopía Electrónica de Rastreo , Salmonella enteritidis/enzimología , Salmonella enteritidis/crecimiento & desarrollo , Succinato Deshidrogenasa/antagonistas & inhibidores
20.
J Oral Sci ; 62(1): 57-61, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31996524

RESUMEN

Porphyromonas gingivalis (P. gingivalis) is one of the major pathogenic bacteria of periodontitis or peri-implantitis. P. gingivalis tends to attach to the implant's neck with the formation of biofilm, leading to peri-implantitis. d-arginine has been shown to have a potential antimicrobial role. In this study, P. gingivalis was cultured in Brain Heart Infusion broth together with d-arginine. After 3 days (inhibition) or 6 days (dissociation), these were characterized using crystal violet (CV) staining for the biofilm, extracellular polysaccharide (EPS) production from the biofilm, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay for biofilm activation. Furthermore, the P. gingivalis biofilm was observed by scanning electron microscopy (SEM). d-arginine effectively reduced biomass accumulation and promoted dissociation at concentrations of ≥50 mM and 100 mM, respectively. Through CV staining, d-arginine concentrations of EPS production from the biofilm for inhibition and dissociation effects was ≥50 mM and 100 mM, respectively. In addition, d-arginine affected biofilm activation for the corresponding concentrations: ≥60 mM for inhibition and ≥90 mM for dispersal. Under SEM observation, d-arginine changed the P. gingivalis biofilm structure in relatively high concentrations for inhibition or dissociation, respectively. The authors concluded that d-arginine could inhibit the formation of P. gingivalis biofilm and promote the dissociation of P. gingivalis biofilm.


Asunto(s)
Periimplantitis , Porphyromonas gingivalis , Arginina , Biopelículas , Humanos , Microscopía Electrónica de Rastreo
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