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1.
Lasers Med Sci ; 39(1): 217, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145805

RESUMO

This in vitro study aimed to investigate potential changes in the color and roughness of dental enamel resulting from the use of different toothpaste formulations during bleaching with violet LED light (405 nm). Sixty specimens of bovine incisors, each measuring 6 × 6 × 3 mm, were segregated into six distinct experimental groups based on their respective treatments (n = 10): C + VL: Brushing with Colgate® Total 12 + bleaching with violet LED; LB + VL: Brushing with Colgate® Luminous White Brilliant + bleaching with violet LED; LI + VL: Brushing with Colgate® Luminous White Instant + violet LED bleaching; C: Brushing with Colgate® Total 12; LB: Brushing with Colgate® Luminous White Brilliant; LI: Brushing with Colgate® Luminous White Instant. The examined variables included alterations in color (∆L*, ∆a*, ∆b*, ∆Eab, and ∆E00), surface roughness (Ra), and scanning electron microscopy observations. No statistically significant distinctions emerged in total color variations (∆E00 and ∆E) among the groups under scrutiny. Notably, the groups that employed Colgate® Luminous White Instant displayed elevated roughness values, irrespective of their association with violet LED, as corroborated by scanning electron microscopy examinations. It can be concluded that whitening toothpastes associated to violet LED do not influence the color change of dental enamel in fifteen days of treatment. Toothpastes with a higher number of abrasive particles showed greater changes in enamel roughness, regardless of the use of violet LED.


Assuntos
Cor , Esmalte Dentário , Propriedades de Superfície , Clareadores Dentários , Clareamento Dental , Cremes Dentais , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/efeitos da radiação , Bovinos , Animais , Cremes Dentais/química , Clareamento Dental/métodos , Clareamento Dental/efeitos adversos , Propriedades de Superfície/efeitos dos fármacos , Clareadores Dentários/efeitos adversos , Técnicas In Vitro , Microscopia Eletrônica de Varredura
2.
Braz J Biol ; 84: e280570, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39109714

RESUMO

Anthocyanins are known as an antioxidant, and their water-soluble purple-colored pigments are very nutritive. Therefore, the present study investigated the antioxidant activity of black rice anthocyanins nano-composite against infertility induced by AlCl3 in rats. Anthocyanin silver nanoparticles (An-AgNPs) were prepared by reducing black rice anthocyanin with the metallic ions. Antioxidant activity (DPPH %) of anthocyanin was determined. Also, the morphology of (An-AgNPs) was examined by scanning electron microscopy (SEM). Albino rats were divided into five groups (negative control (NC): fed on basel diet, positive control (PC): treated with AlCl3 (34 mg/kg bw) for seventy days, and three other groups treated with AlCl3 (34 mg/kg bw) + An-AgNPs at 10, 15, and 20 mg/kg, b.w/ day, respectively for seventy days. Serum testosterone, LH, FSH, and estradiol were measured. Additionally, Sperm motility, Sperm count (Testicular and Epididymal), fructose in semen, and semen quality were determined. The values of the anthocyanin component and DPPH radical scavenging activity obtained were 3603.82±6.11 mg CCE/g and 84.62±1.98, respectively. An-AgNPs shows tend to agglomerate, particles are uniform in size and shape, and the diameter of the particles ranges between 70nm to 130nm. LH, estradiol and testosterone levels increased significantly in rats treated with An-AgNPs 10, 15, 20 mg/kg b.w+ AlCl3 (34 mg/kg bw) also exhibited significantly higher sperm motility, sperm count, and daily sperm production, and decreased sperm transit rate than G2. In comparison to G2, animals treated with AlCl3 (34 mg/kg bw) + An-AgNPs 10, 15, 20 mg/kg b.w(G3 to G5) had significantly higher semen and semen quality (P 0.05). We can conclude that the An-AgNPs showed a strong effect against infertility induced by AlCl3; this represents a suitable natural supply of biological substances for medicine and anthocyanins could be considered the ideal ingredients against oxidative stress-induced infertility.


Assuntos
Cloreto de Alumínio , Compostos de Alumínio , Antocianinas , Antioxidantes , Nanopartículas Metálicas , Oryza , Ratos Wistar , Prata , Animais , Antocianinas/farmacologia , Antocianinas/análise , Masculino , Antioxidantes/farmacologia , Oryza/química , Prata/química , Infertilidade Masculina , Cloretos , Motilidade dos Espermatozoides/efeitos dos fármacos , Nanocompostos/química , Microscopia Eletrônica de Varredura , Ratos , Testosterona/sangue , Contagem de Espermatozoides , Análise do Sêmen
3.
J Morphol ; 285(8): e21762, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39129184

RESUMO

Siphons are tubular organs formed by fusion and posterior extension of the marginal mantle folds. They are supposed to have performed key roles in the evolution of bivalves by enabling these animals to occupy several ecological niches. However, anatomical details of these organs are scarce for one of the most diverse lineages of tropical bivalves, the superfamily Tellinoidea. We investigated the siphonal morphology of 15 species, sampling five tellinoidean families, by integrating scanning electron microscopy, confocal microscopy, and histology. The siphons revealed variations in length, pigmentation, tentacles, papillae, and number of nerve cords. Due to the presence of sensorial structures, such as papillae and tentacles, we reclassify the siphons of Tellinoidea from type A to A+. Additional anatomical patterns were identified at family and genus levels. For example, the incurrent siphon shorter than the excurrent and 24 tentacles are putative synapomorphies of Donacidae. We also highlight shared siphonal traits between Donacidae and Solecurtidae as well as between Semelidae and Tellinidae. In addition, our data support the idea of Psammobiidae as a paraphyletic lineage. Overall, we provide an extensive comparative data set on siphonal traits with significant relevance for bivalve taxonomy, functional anatomy, and evolutionary investigations.


Assuntos
Bivalves , Animais , Bivalves/anatomia & histologia , Microscopia Eletrônica de Varredura , Evolução Biológica , Filogenia , Anatomia Comparada
4.
J Dent ; 149: 105283, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39096997

RESUMO

OBJECTIVE: The aim of this study was to evaluate the effect of an adhesive loaded with 0.2 % copper (Cu) and 5 % zinc oxide (ZnO) nanoparticles (Nps) on its adhesive properties and enzymatic activity at the hybrid layer ex vivo in a randomized clinical model. METHODS: Fifteen patients participated in this study, and a total of 30 third molars were used. Occlusal cavities (4 × 4 × 2 mm) were made in each tooth, and randomly divided into 2 groups: (i) Experimental group: commercial adhesive loaded with 0.2wt % CuNps and 5wt % ZnONps; and (ii) Control Group: non-loaded commercial adhesive. Teeth were restored with resin composite. Thirty days later, extractions were performed. Extracted teeth were longitudinally sectioned. Nps in powder were characterized by field emission scanning electron microscope (FE-SEM) and energy dispersive X-ray (EDX) analysis. Microtensile bond strength (µTBS), degree of conversion (DC), and nanoleakeage (NL) tests were executed. In situ zymography (Zym) was performed to evaluate the gelatinolytic activity at the hybrid layer. Student's t-test (α = 0.05) was applied for all tests. RESULTS: µTBS and DC did not show significant differences (p > 0.05) between both groups. However, NL and gelatinolytic activity at the hybrid layer showed significant values (p < 0.05) for experimental group in comparison with control group. CONCLUSION: The addition of 0.2 % CuNps and 5 % ZnONps to a universal adhesive decreases NL and gelatinolytic activity at the hybrid layer, without jeopardizing its adhesive properties. SIGNIFICANCE: This randomized clinical trial with ex vivo analysis demonstrate that a commercial adhesive modified with 0.2wt % Cu and 5wt % ZnO Nps that does not affect its adhesive properties, reducing gelatinolytic activity and nanoleakage at the hybrid layer, which should contribute to an improvement of long term bonding-dentine clinical performance.


Assuntos
Resinas Compostas , Cobre , Colagem Dentária , Microscopia Eletrônica de Varredura , Resistência à Tração , Óxido de Zinco , Humanos , Óxido de Zinco/química , Cobre/química , Colagem Dentária/métodos , Resinas Compostas/química , Nanopartículas/química , Adesivos Dentinários/química , Dentina/efeitos dos fármacos , Dentina/enzimologia , Teste de Materiais , Masculino , Cimentos de Resina/química , Adulto , Feminino , Propriedades de Superfície , Cimentos Dentários/química , Dente Serotino , Restauração Dentária Permanente/métodos , Espectrometria por Raios X
5.
J Dent ; 149: 105291, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39117099

RESUMO

OBJECTIVE: This study aims to synthesize, characterize, and assess the penetration of hydrogen peroxide (HP), color change (CC), and surface morphology changes after the application of two distinct nano-hydroxyapatite (nano-HAp). METHODS: Two nano-HAp were previously synthesized by co-precipitation: one with rod-shaped particles (RS) and the other with spherical-shaped particles (SS). The surface charge of the nano-HAp particles was determined at varying pH levels and characterized by X-ray diffraction patterns and Fourier transform infrared spectroscopy. The morphology of the samples was assessed using scanning electron microscopy (SEM). The nano-HAp particles were applied before the dental bleaching procedure. Forty teeth were divided into four groups (n = 10) according to the bleaching treatment: no treatment, bleaching with 35 % HP only, RS application and bleaching with 35 % HP, and SS application and bleaching with 35 % HP. HP concentration (µg mL-1) was measured using UV-Vis, while CC was evaluated with a digital spectrophotometer (ΔEab, ΔE00 and WID). Additionally, four teeth from each group were selected for SEM analysis. Statistical analysis encompassed one-way ANOVA, Tukey's, and Dunnet's tests. RESULTS: RS and SS were successfully synthesized by coprecipitation, primarily differing in pH during synthesis. Both variations of nano-HAp morphology significantly reduced HP diffusion into the pulp chamber (p < 0.001). Regarding enamel morphology, groups analyzed post dental bleaching exhibited greater HAp deposition on the enamel surface. Notably, this deposition did not impede CC. SIGNIFICANCE: The utilization of different nano-HAp morphologies prior to dental bleaching appears to be a promising strategy for mitigating adverse effects associated with dental bleaching procedures.


Assuntos
Esmalte Dentário , Peróxido de Hidrogênio , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Clareadores Dentários , Clareamento Dental , Difração de Raios X , Clareamento Dental/métodos , Esmalte Dentário/efeitos dos fármacos , Humanos , Clareadores Dentários/química , Clareadores Dentários/administração & dosagem , Espectroscopia de Infravermelho com Transformada de Fourier , Concentração de Íons de Hidrogênio , Cor , Nanopartículas/química , Hidroxiapatitas/química , Durapatita/química , Teste de Materiais
6.
Plant Physiol Biochem ; 215: 109049, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39151366

RESUMO

Integrating agricultural, chemical, and technological knowledge is crucial for developing bio-nanotechnologies to improve agricultural production. This study explores the innovative use of biopolymeric coatings, based on sodium alginate and sodium alginate + Laponite® (nanoclay), containing biostimulants (tryptophol and thymol) or not, on garlic cloves. These coatings were analyzed using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR-ATR), and scanning electron microscopy (SEM). Greenhouse bioassays showed improvements in garlic shoot plant biomass with both treatments: sodium alginate biopolymer and sodium alginate biopolymer plus Laponite®. In the field experiment, garlic plants treated with sodium alginate, in combination with conventional pesticide treatments, resulted in better quality garlic bulbs, where larger garlics were harvested in this treatment, reducing commercial losses. In tropical garlic crops, obtaining plants with greater initial vigor is essential. Our results highlight the potential of these bio-nanotechnological strategies to enhance garlic propagation, ensuring environmental protection and food security.


Assuntos
Alho , Alho/química , Biopolímeros/química , Alginatos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Microscopia Eletrônica de Varredura , Nanotecnologia/métodos
7.
Acta Parasitol ; 69(3): 1396-1402, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39112766

RESUMO

PURPOSE: In this study, 143 lutjanid fishes representing four different species from the Northeast coast off Brazil were analyzed for parasites. The aim of the present study is to provide a detailed redescription of R. (I.) vicentei, collected from lutjanid fishes in Brazil, including the first observation of the species using scanning electron microscopy (SEM). METHODS: Nematodes found clarified in a crescent glycerin series, were photographed and measured (in mm), and some specimens destined for SEM. The Illustrations were made using an optical microscope with a drawing tube. RESULTS: Nematodes found were identified as Raphidascaris (Ichthyascaris) vicentei, infecting 6.29% of the examined fish. Detailed morphological analysis revealed the following characteristics observed for the first time in this species: labial papillae, narrow lateral alae and the detailed structure of male spicules. These contributions help filling the gaps in the literature and expand the knowledge of this parasite morphology. CONCLUSIONS: The presence of R. (I.) vicentei in four lutjanid species may indicates low host specificity, highlighting its adaptability to different hosts. Furthermore, new host records are given. This research provides the most comprehensive morphological description of R. (I.) vicentei to date, generating crucial insights for a better understanding of the parasitic biodiversity off the Brazilian Northeastern coast of Brazil, as well as establishing foundation for future investigations on the ecology and impacts of these parasites in fish populations from this region.


Assuntos
Doenças dos Peixes , Microscopia Eletrônica de Varredura , Animais , Brasil , Doenças dos Peixes/parasitologia , Microscopia Eletrônica de Varredura/veterinária , Masculino , Feminino , Peixes/parasitologia , Infecções por Ascaridida/veterinária , Infecções por Ascaridida/parasitologia , Infecções por Ascaridida/epidemiologia , Ascaridoidea/isolamento & purificação , Ascaridoidea/classificação , Ascaridoidea/anatomia & histologia , Ascaridoidea/ultraestrutura
8.
Acta Parasitol ; 69(3): 1600-1612, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39162922

RESUMO

OBJECTIVES: An integrative taxonomic description of Aponurus laguncula (Lecithasteridae), a digenean parasitic species of Chaetodipterus faber (Acanthuriformes) from Brazilian Southeast, is provided. Morphological techniques, as whole mounted slides, histology and scanning electron microscopy, and molecular analyses supported that integrative description. METHODS: Fifteen digenean specimens were stained in hydrochloric carmine and mounted on permanent slides. Two specimens were stained in hematoxylin and eosin following histological routine processing. Four parasites were dehydrated through a graded ethanol series, critical point dried with carbon dioxide and coated with gold to scanning electron microscopy analysis. Sequence of the large ribosomal subunit (28S rDNA) gene was generated and used to construct a phylogeny based on maximum likelihood and Bayesian inference analyses. RESULTS: Morphological description and morphometric data obtained in present study were in accordance with previous studies of the species. Use of another morphological techniques, as scanning electron microscopy and histology, corroborated the observed features of whole mounted slides. Also, they provided a better observation of previous reported characteristics and new features reporting, such as an elongated hermaphroditic duct, a smooth tegument and cells that compose the prostatic gland. The molecular sequence obtained in the present study formed a robust clade with available sequences of species of Aponurus. CONCLUSIONS: The integrative taxonomic approach successfully combined morphological observations, including both previously reported features and new descriptions from histological and electron microscopy analyses, with molecular data to identify these specimens as A. laguncula. Moreover, the detailed characterization of structures, such as the gonads in A. laguncula, that would be challenging to analyze using a single technique, was possible. Further molecular studies with less conserved genetic markers should be conducted to understand phylogenetic relationships between Aponurus species.


Assuntos
Doenças dos Peixes , Microscopia Eletrônica de Varredura , Filogenia , Trematódeos , Infecções por Trematódeos , Animais , Brasil , Doenças dos Peixes/parasitologia , Trematódeos/genética , Trematódeos/classificação , Trematódeos/isolamento & purificação , Trematódeos/ultraestrutura , Trematódeos/anatomia & histologia , Microscopia Eletrônica de Varredura/veterinária , Infecções por Trematódeos/veterinária , Infecções por Trematódeos/parasitologia , RNA Ribossômico 28S/genética , Peixes/parasitologia , DNA Ribossômico/genética , DNA de Helmintos/genética
9.
Food Res Int ; 191: 114728, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39059922

RESUMO

With the increasing need to promote healthy and sustainable diets, seaweeds emerge as an environmentally friendly food source, offering a promising alternative for food production. The aim of this study was to characterize the brown seaweed Sargassum filipendula from the coast of São Paulo, Brazil, regarding its nutritional and techno-functional properties using two dehydration methods, oven drying and lyophilized. A commercial dried sample was used as a control. Analyses of proximate composition, mineral determination, amino acid determination, antioxidant capacity, pH, color, scanning electron microscopy, X-ray diffraction, thermal properties, Fourier-transform infrared spectroscopy, and techno-functional properties were performed. Seaweed flours showed significant differences in physicochemical composition, with dietary fiber content of seaweed flours exceeding 70 %. Glutamic and aspartic acids were the most abundant amino acids, with contents of 88.56 and 56.88 mg/g of protein in Sargassum oven drying. Both for antioxidant potential and bioactive compounds, Sargassum lyophilized flours showed the highest levels of compounds. Sargassum lyophilized exhibited lighter color compared to Sargassum oven drying and Sargassum commercial. Emulsion formation, foam formation capacity and stability were higher in Sargassum lyophilized, as well as water and oil absorption. The results suggest that seaweeds can be used to formulate a wide variety of food products, such as sausages, bread, cakes, soups, and sauces.


Assuntos
Antioxidantes , Liofilização , Valor Nutritivo , Sargassum , Alga Marinha , Sargassum/química , Antioxidantes/análise , Alga Marinha/química , Fibras na Dieta/análise , Brasil , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Aminoácidos/análise , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Dessecação/métodos
10.
Oper Dent ; 49(4): 455-464, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38978307

RESUMO

OBJECTIVE: To evaluate the effect of polyethylene fiber-reinforcement on the fracture resistance and fracture mode of extensive resin-based composite (RBC) restorations in structurally compromised maxillary premolars. METHODS AND MATERIALS: Maxillary premolars (54) with specific dimensions and extracted for orthodontic reasons were used. Following mesio-occluso-distal (MOD) cavity preparation and endodontic access, teeth were randomly assigned to one of three restorative protocols (n=18): RBC applied incrementally (I) or reinforced with woven polyethylene fibers (Ribbond) placed horizontally (H) or U-shaped (U). Restored teeth were stored for 45 days in distilled water at 37°C and then loaded monotonically until fracture. Half of the specimens in each group received axial loading (A) and the other half was loaded paraxially (PA). Fracture load data was assessed using two-way analysis of variance and Tukey's post hoc test for multiple comparisons (α=0.05). The fracture initiation and propagation path were analyzed using stereomicroscopy and scanning-electron microscopy. RESULTS: No significant differences were observed for the fracture strength among loading configurations, except for groups IA (825 N) and HA (553 N). Fracture initiated and propagated mainly at and through the RBC restoration in the I group, whereas a shift to the interface was observed in both polyethylene fiber-reinforced groups. Blocking and bridging of cracks were identified around the fibers, especially in specimens of group U. CONCLUSIONS: Incorporation of woven polyethylene fibers to reinforce extensive MOD resin-based composite restorations on endodontically treated premolars reduced the occurrence of cohesive fractures in the restorative material but was unable to increase the fracture resistance of the affected teeth.


Assuntos
Dente Pré-Molar , Resinas Compostas , Falha de Restauração Dentária , Restauração Dentária Permanente , Análise do Estresse Dentário , Humanos , Resinas Compostas/uso terapêutico , Resinas Compostas/química , Técnicas In Vitro , Restauração Dentária Permanente/métodos , Polietileno/química , Polietileno/uso terapêutico , Microscopia Eletrônica de Varredura , Teste de Materiais , Fraturas dos Dentes/prevenção & controle , Dente não Vital/terapia , Polietilenos
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