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1.
Food Res Int ; 186: 114364, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729726

RESUMO

With the aim of reintroducing wheat grains naturally contaminated with mycotoxins into the food value chain, a decontamination strategy was developed in this study. For this purpose, in a first step, the whole wheat kernels were pre-treated using cold needle perforation. The pore size was evaluated by scanning electron microscopy and the accessibility of enzymes and microorganisms determined using fluorescent markers in the size range of enzymes (5 nm) and microorganisms (10 µm), and fluorescent microscopy. The perforated wheat grains, as well as non-perforated grains as controls, were then incubated with selected microorganisms (Bacillus megaterium Myk145 and B. licheniformis MA572) or with the enzyme ZHD518. The two bacilli strains were not able to significantly reduce the amount of zearalenone (ZEA), neither in the perforated nor in the non-perforated wheat kernels in comparison with the controls. In contrast, the enzyme ZHD518 significantly reduced the initial concentration of ZEA in the perforated and non-perforated wheat kernels in comparison with controls. Moreover, in vitro incubation of ZHD518 with ZEA showed the presence of two non-estrogenic degradation products of ZEA: hydrolysed zearalenone (HZEA) and decarboxylated hydrolysed ZEA (DHZEA). In addition, the physical pre-treatment led to a reduction in detectable mycotoxin contents in a subset of samples. Overall, this study emphasizes the promising potential of combining physical pre-treatment approaches with biological decontamination solutions in order to address the associated problem of mycotoxin contamination and food waste reduction.


Assuntos
Contaminação de Alimentos , Triticum , Zearalenona , Zearalenona/análise , Triticum/química , Triticum/microbiologia , Contaminação de Alimentos/análise , Bacillus megaterium/enzimologia , Descontaminação/métodos , Microbiologia de Alimentos , Manipulação de Alimentos/métodos , Bacillus/enzimologia , Sementes/química , Sementes/microbiologia , Microscopia Eletrônica de Varredura
2.
Am J Dent ; 37(2): 71-77, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38704849

RESUMO

PURPOSE: To investigate the effect of painless low-power Er:YAG laser irradiation of conventional and polymer-infiltrated ceramic network (PICN) type CAD-CAM resin-based composites (RBCs) on resin bonding. METHODS: An Er:YAG laser system, phosphoric acid etchant, universal adhesive, RBC, and two types of CAD-CAM RBC block were used. Microtensile bond strength, fracture mode, scanning electron microscopy (SEM) observations of bonding interfaces and CAD-CAM surfaces, and surface roughness of ground and pretreated surfaces were investigated. As pretreatment methods, low-power Er:YAG laser irradiation and air-abrasion with alumina particles were used. RESULTS: The effect of low-power Er:YAG laser irradiation of CAD-CAM RBCs on bonding to repair resin varied depending on the type of CAD-CAM RBCs. CLINICAL SIGNIFICANCE: The low-power Er:YAG laser irradiation of the conventional CAD-CAM RBCs was shown to be effective as a surface pretreatment for resin bonding, while the laser irradiation of PICN-type CAD-CAM RBCs was not effective.


Assuntos
Resinas Compostas , Desenho Assistido por Computador , Colagem Dentária , Lasers de Estado Sólido , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Resinas Compostas/química , Resistência à Tração , Teste de Materiais , Humanos , Cerâmica/química , Condicionamento Ácido do Dente
3.
Am J Dent ; 37(2): 91-100, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38704852

RESUMO

PURPOSE: To compare the internal adaptation of restorative systems bonded to mid-coronal and gingival dentin using light-cured, chemical-cured, and dual-cured adhesives, both immediately and after aging. METHODS: 60 molars were selected and received occluso-mesial preparations with dentin gingival margins. Restorations were performed using different restorative systems with light-cured, chemical-cured, and dual-cured adhesives. Internal adaptation was assessed by examining the percentage of continuous margin (%CM) at the pulpal and gingival dentin under a scanning electron microscope at x200 magnification. Half of the teeth were stored in sterile water for 24 hours, while the other half underwent 10,000 thermal cycles. Micro-morphological analysis was conducted on representative samples at x1,000 magnification. RESULTS: The restorative system with light-cured adhesive exhibited significantly lower %CM values at the gingival dentin, particularly after aging. Aging had a negative impact on the %CM values of the pulpal and gingival dentin in restorative systems with light-cured and dual-cured adhesives. Regional dentin variations influenced the %CM values, especially after aging, regardless of the restorative system used. The tested restorative system with chemical-cured adhesive is preferable for achieving improved internal adaptation when bonding to both mid-coronal and gingival dentin, compared to the other tested systems. CLINICAL SIGNIFICANCE: The study highlights the variations in adhesive performance between different regional dentin areas using the tested restorative systems.


Assuntos
Resinas Compostas , Gengiva , Humanos , Resinas Compostas/química , Polpa Dentária , Restauração Dentária Permanente , Adaptação Marginal Dentária , Microscopia Eletrônica de Varredura , Dentina , Cimentos de Resina/química , Dente Molar , Técnicas In Vitro , Cura Luminosa de Adesivos Dentários , Teste de Materiais
4.
Pak J Pharm Sci ; 37(1(Special)): 245-255, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38747276

RESUMO

Aripiprazole (ARI), an antipsychotic having low solubility and stability. To overcome this, formation of binary and ternary using inclusion complexes of Methyl-ß-cyclodextrin (MßCD) /Hydroxy propyl beta cyclodextrin (HPßCD) and L-Arginine (ARG)/ Lysine (LYS) are analyzed by dissolution testing and phase stability study along with their complexation efficacy and solubility constants made by physical mixing. Inclusion complexes with ARG were better than LYS and prepared by solvent evaporation and lyophilization method as well. They are characterized by Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (AT-FTIR), X-ray powder diffractometry (XRD), Differential Scanning Calorimetry (DSC), Scanning electron microscopy (SEM) and Thermal gravimetric analysis (TGA). The bond shifting in AT-FTIR confirmed the molecular interactions between host and guest molecules. The SEM images also confirmed a complete change of drug morphology in case of ternary inclusion complexes prepared by lyophilization method for both the polymers. ARI: MßCD: ARG when used in the specific molar ratio of 1:1:0.27 by prepared by lyophilization method has 18 times best solubility while ARI:HPßCD:ARG was 7 times best solubility than pure drug making MßCD a better choice than HPßCD. Change in the molar ratio will cause loss of stability or solubility. Solvent evaporation gave significant level of solubility but less stability.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina , Arginina , Aripiprazol , Varredura Diferencial de Calorimetria , Lisina , Solubilidade , beta-Ciclodextrinas , Aripiprazol/química , Arginina/química , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina/química , Lisina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Liofilização , Antipsicóticos/química , Estabilidade de Medicamentos , Microscopia Eletrônica de Varredura , Composição de Medicamentos , Química Farmacêutica/métodos
5.
Pak J Pharm Sci ; 37(1(Special)): 235-243, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38747275

RESUMO

Stimulus-responsive mesoporous silica nanoparticles (MSNs) have displayed great potentiality for controlled-release and targeted drug delivery. In the current work, a supercritical fluid method was utilized to successfully prepare cinnamon oil loaded into chitosan grafted MSNs (CO@CS-MSNs). The influencing factors of drug loads, such as pressure, temperature, impregnation time and depressure time, were investigated. The structure of CO@CS-MSNs was demonstrated with Fourier-transform infrared (FT-IR) spectroscopy, transmission electron microscope (TEM), scanning electron microscopy (SEM), thermogravimetry (TG) as well as X-ray diffraction (XRD). The drug release assays in vitro at various pH conditions displayed that CO@CS-MSNs had an excellent pH-responsive release behavior, which confirmed that CO was loaded successfully into the CO@CS-MSNs. The findings indicated that the supercritical fluid approach is a non-destructive and efficient approach for stimulus-responsive MSNs, which is expected to further expand its application range.


Assuntos
Dióxido de Carbono , Quitosana , Cinnamomum zeylanicum , Liberação Controlada de Fármacos , Nanopartículas , Dióxido de Silício , Quitosana/química , Dióxido de Silício/química , Nanopartículas/química , Concentração de Íons de Hidrogênio , Dióxido de Carbono/química , Porosidade , Cinnamomum zeylanicum/química , Portadores de Fármacos/química , Óleos Voláteis/química , Óleos Voláteis/administração & dosagem , Difração de Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Microscopia Eletrônica de Varredura , Preparações de Ação Retardada
6.
J Biomed Mater Res B Appl Biomater ; 112(5): e35416, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38747324

RESUMO

The bone formation response of ceramic bone graft materials can be improved by modifying the material's surface and composition. A unique dual-phase ceramic bone graft material with a nanocrystalline, hydroxycarbanoapatite (HCA) surface and a calcium carbonate core (TrelCor®-Biogennix, Irvine, CA) was characterized through a variety of analytical methods. Scanning electron microscopy (SEM) of the TrelCor surface (magnification 100-100,000X) clearly demonstrated a nanosized crystalline structure covering the entire surface. The surface morphology showed a hierarchical structure that included micron-sized spherulites fully covered by plate-like nanocrystals (<60 nm in thickness). Chemical and physical characterization of the material using X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscopy Energy Dispersive X-ray Spectroscopy (SEM-EDX) showed a surface composed of HCA. Analysis of fractured samples confirmed the dual-phase composition with the presence of a calcium carbonate core and HCA surface. An in vitro bioactivity study was conducted to evaluate whether TrelCor would form a bioactive layer when immersed in simulated body fluid. This response was compared to a known bioactive material (45S5 bioactive glass - Bioglass). Following 14-days of immersion, surface and cross-sectional analysis via SEM-EDX showed that the TrelCor material elicited a bioactive response with the formation of a bioactive layer that was qualitatively thicker than the layer that formed on Bioglass. An in vivo sheep muscle pouch model was also conducted to evaluate the ability of the material to stimulate an ectopic, cellular bone formation response. Results were compared against Bioglass and a first-generation calcium phosphate ceramic that lacked a nanocrystalline surface. Histology and histomorphometric analysis (HMA) confirmed that the TrelCor nanocrystalline HCA surface stimulated a bone formation response in muscle (avg. 11% bone area) that was significantly greater than Bioglass (3%) and the smooth surface calcium phosphate ceramic (0%).


Assuntos
Substitutos Ósseos , Nanopartículas , Animais , Substitutos Ósseos/química , Nanopartículas/química , Cerâmica/química , Teste de Materiais , Durapatita/química , Ovinos , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X , Transplante Ósseo
7.
An Acad Bras Cienc ; 96(2): e20230373, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38747835

RESUMO

Bioactive substances can be found in wine lees, a waste from the winemaking industry. This work developed two formulations, a nanoemulsion with coconut oil (NE-OC) and a nanoemulsion with coconut oil and 0.5% of wine lees extract (NE-OC-Ext), to investigate their effect on untreated, bleached, and bleached-colored hair. The oil-in-water (O/W) nanoemulsions were prepared with coconut oil, TweenTM 80, SpanTM 80, AristoflexTM AVC, Conserve NovaMit MFTM, wine lees extract, and deionized water. The hydration measurements were carried out using a Corneometer® CM 825 with the capacitance method. Scanning electron microscopy (SEM) was used to characterize the effect of formulations on hair fibers. Differential Thermal Analysis (DTA) was to assess the thermal stability and compatibility of wine lees and coconut oil in formulations. Compared to NE-OC, NE-OC-Ext showed a greater hydration effect on bleached-colored hair. DTA showed that NE-OC-Ext presented a smaller number of exothermic degradation events than those of NE-OC, suggesting good interaction and compatibility of the wine lees extract in this formulation. This study highlights the value of wine lees, a residue from the winemaking process, and its possibility of use as raw material for the cosmetic hair industry since it shows a greater moisturizing potential in colored hair.


Assuntos
Óleo de Coco , Emulsões , Vinho , Vinho/análise , Óleo de Coco/química , Microscopia Eletrônica de Varredura , Cabelo/química , Cabelo/efeitos dos fármacos , Humanos , Química Verde/métodos
8.
Water Sci Technol ; 89(9): 2558-2576, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38747967

RESUMO

In this study, membranes blended with polysulfone (PSU) and polyetherimide (PEI) polymers in different ratios were fabricated. Their potential to remove pollutants from rivers, which are a potential drinking water source, was investigated. Scanning electron microscopy analysis revealed that the PSU membranes had a dense and homogeneous layer, whereas the addition of PEI formed a spongy substrate. The water content of the fabricated membranes varied between 5.37 and 22.42%, porosities 28.73-89.36%, contact angles 69.18-85.81%, and average pure water fluxes 257.25-375.32 L/m2 h. The blended membranes removed turbidity, chloride, alkalinity, conductivity, sulfate, iron, manganese, and total organic carbon up to 98.32, 92.28, 96.87, 90.67, 99.58, 94.63, 97.48, and 79.11%, respectively. These results show that when PEI was added to the PSU polymer, the filtration efficiency increased owing to an increase in the hydrophilicity of the membranes. Blending these two polymers enabled the optimization of membrane properties such as permeability, selectivity, and mechanical strength. In addition, membrane fabrication processes are simple and incur low costs.


Assuntos
Filtração , Membranas Artificiais , Polímeros , Sulfonas , Polímeros/química , Sulfonas/química , Filtração/métodos , Purificação da Água/métodos , Poluentes Químicos da Água/química , Microscopia Eletrônica de Varredura
9.
Invertebr Syst ; 382024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38744495

RESUMO

Ninetinae is a group of small to tiny short-legged spiders largely restricted to arid habitats. Among daddy-long-legs spiders (Pholcidae) this is by far the least diverse subfamily but this may partly be a result of inadequate collecting, poor representation in collections or scientific neglect. We build on a large recent collection of the ninetine genus Papiamenta Huber, 2000 from the Leeward Antilles and use cytochrome oxidase 1 (COI ) sequences, extensive scanning electron microscopy data, transmission electron microscopy data and karyotyping to analyse this geographically isolated and poorly known island genus. COI sequences support the split between the two morphologically distinct species on Curaçao but genetic distances between these are surprisingly low (7.4-9.8%; mean 8.6%). The type species P. levii (Gertsch, 1982) may include more than one species but COI and morphology suggest conflicting clade limits. A third species, P. bonay Huber sp. nov. is newly described from Bonaire. Our data on sperm ultrastructure and karyology are puzzling as these suggest different phylogenetic affinities of Papiamenta to other genera. Males transfer sperm as individual sperm (cleistosperm), agreeing with the putative closest relatives as suggested by molecular data, the North American genera Pholcophora and Tolteca . The sex chromosome system (X 1 X 2 X 3 Y ) of P. levii , however, is as in the South American Ninetinae genera Gertschiola and Nerudia but different from the putative closest relatives. ZooBank: urn:lsid:zoobank.org:pub:7A6A2E84-3A61-4637-AF6F-0E31A9FA79A8.


Assuntos
Filogenia , Aranhas , Animais , Aranhas/genética , Aranhas/classificação , Masculino , Complexo IV da Cadeia de Transporte de Elétrons/genética , Especificidade da Espécie , Feminino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
10.
BMC Oral Health ; 24(1): 564, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745154

RESUMO

BACKGROUND: Alterations in the mechanical properties of the materials utilized in orthodontic appliances could affect the working properties of the appliances, thereby affecting clinical progress and outcome. Numerous studies have confirmed the correlation between alloy corrosion and raised surface roughness, which has a direct impact on the working characteristics of orthodontic archwires. METHODS: Thirty nickel-titanium (NiTi) orthodontic archwires were utilized in this study. Patients were randomly selected and allocated into three groups according to the randomization plan; (The control group): subjects practiced regular oral hygiene; (The fluoride group): subjects used fluoride for intensive prophylaxis; (The chlorhexidine group): subjects used chlorhexidine. Representative samples were evaluated by SEM, and then SEM images with high resolution were examined using Image J software to determine the surface roughness and obtain the results for further statistical analysis. RESULTS: Our findings indicated a significant difference was found between the three groups regarding the anterior and posterior parts between the control and the two other groups and a non-significant difference between NaF and CHX groups. Overall, the p-value for group comparisons was 0.000 for both parts, indicating a highly significant difference especially between the control and NaF groups. CONCLUSION: Mouthwashes containing sodium fluoride demonstrated more significant surface alterations than the control and CHX groups and should be prescribed in accordance with orthodontic materials to reduce side effects.


Assuntos
Ligas , Clorexidina , Ligas Dentárias , Microscopia Eletrônica de Varredura , Níquel , Fios Ortodônticos , Fluoreto de Sódio , Propriedades de Superfície , Humanos , Fluoreto de Sódio/uso terapêutico , Clorexidina/uso terapêutico , Corrosão , Ligas Dentárias/química , Níquel/química , Titânio/química , Cariostáticos/uso terapêutico , Cariostáticos/química , Masculino , Feminino , Adulto Jovem , Antissépticos Bucais/uso terapêutico , Antissépticos Bucais/química , Processamento de Imagem Assistida por Computador/métodos , Adolescente , Adulto , Higiene Bucal
11.
Luminescence ; 39(5): e4768, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38719590

RESUMO

In this study, we synthesize nanostructured nickel oxide (NiO) and doped cobalt (Co) by combining nickel(II) chloride hexahydrate (NiCl2.6H2O) and sodium hydroxide (NaOH) as initial substances. We analyzed the characteristics of the product nanostructures, including their structure, optical properties, and magnetic properties, using various techniques such as x-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet absorption spectroscopy (UV-Vis), Fourier transform infrared (FTIR) spectroscopy, and vibrating sample magnetometers (VSM). The NiO nanoparticles doped with Co showed photocatalytic activity in degrading methylene blue (MB) dye in aqueous solutions. We calculated the degradation efficiencies by analyzing the UV-Vis absorption spectra at the dye's absorption wavelength of 664 nm. It was observed that the NiO-doped Co nanoparticles facilitated enhanced recombination and migration of active elements, which led to more effective degradation of organic dyes during photocatalysis. We also assessed the electrochemical properties of the materials using cyclic voltammetry (CV) and impedance spectroscopy in a 1 mol% NaOH solution. The NiO-modified electrode exhibited poor voltammogram performance due to insufficient contact between nanoparticles and the electrolyte solution. In contrast, the uncapped NiO's oxidation and reduction cyclic voltammograms displayed redox peaks at 0.36 and 0.30 V, respectively.


Assuntos
Cobalto , Eletroquímica , Eletrodos , Nanocompostos , Níquel , Nanocompostos/química , Níquel/química , Cobalto/química , Difração de Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Luminescência , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Fenômenos Magnéticos , Nanopartículas/química , Luz , Catálise , Óxidos/química , Azul de Metileno/metabolismo
12.
J Biomed Opt ; 29(9): 093502, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38715718

RESUMO

Significance: Developing stable, robust, and affordable tissue-mimicking phantoms is a prerequisite for any new clinical application within biomedical optics. To this end, a thorough understanding of the phantom structure and optical properties is paramount. Aim: We characterized the structural and optical properties of PlatSil SiliGlass phantoms using experimental and numerical approaches to examine the effects of phantom microstructure on their overall optical properties. Approach: We employed scanning electron microscope (SEM), hyperspectral imaging (HSI), and spectroscopy in combination with Mie theory modeling and inverse Monte Carlo to investigate the relationship between phantom constituent and overall phantom optical properties. Results: SEM revealed that microspheres had a broad range of sizes with average (13.47±5.98) µm and were also aggregated, which may affect overall optical properties and warrants careful preparation to minimize these effects. Spectroscopy was used to measure pigment and SiliGlass absorption coefficient in the VIS-NIR range. Size distribution was used to calculate scattering coefficients and observe the impact of phantom microstructure on scattering properties. The results were surmised in an inverse problem solution that enabled absolute determination of component volume fractions that agree with values obtained during preparation and explained experimentally observed spectral features. HSI microscopy revealed pronounced single-scattering effects that agree with single-scattering events. Conclusions: We show that knowledge of phantom microstructure enables absolute measurements of phantom constitution without prior calibration. Further, we show a connection across different length scales where knowledge of precise phantom component constitution can help understand macroscopically observable optical properties.


Assuntos
Método de Monte Carlo , Imagens de Fantasmas , Microscopia Eletrônica de Varredura , Espalhamento de Radiação , Microesferas , Imageamento Hiperespectral/métodos , Imageamento Hiperespectral/instrumentação
13.
J Morphol ; 285(5): e21708, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38717945

RESUMO

Guitarfishes and sawfishes are included in the order Rhinopristiformes, which currently encompasses five families: Pristidae, Rhinobatidae, Trygonorrhinidae, Rhinidae and Glaucostegidae. Considering the low number of studies focused on oral structures in Rhinopristiformes and the need to better understand their internal morphology, this study aimed to (1) evaluate and describe the morphological variation of the oropharyngeal denticles of guitarfishes and sawfish; (2) evaluate and describe the ontogenetic and sexual variation of the oropharyngeal denticles of Zapteryx brevirostris; (3) propose characters potentially useful for taxonomic and systematic purposes and (4) discuss the possible functions and advantages of these structures. Tissue samples were taken from the oropharyngeal region of specimens preserved in 70% alcohol and then prepared for visualization in scanning electron microscopy. A new method for sampling the pharynx region is proposed herein. Considerable morphological variation between families and genera was observed. However, no variation between conspecifics was found. Regional variations of denticles when examining a single individual were observed in shape, ornamentation, and orientation. In Zapteryx brevirostris, males had a significantly higher density of denticles in the ventral region than females and lower densities were observed in juveniles. The four characters discussed here are based on the presence of keels, number of cusps, distal end elongation and width/length ratio of the oropharyngeal denticles. Among the possible functions and advantages of these structures are the improvement of food adherence, tissue protection against food abrasion and parasitism, and attenuation of hydrodynamic drag in the oropharyngeal cavity during food ingestion.


Assuntos
Orofaringe , Animais , Orofaringe/anatomia & histologia , Orofaringe/fisiologia , Masculino , Feminino , Microscopia Eletrônica de Varredura
14.
Clin Oral Investig ; 28(6): 305, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722356

RESUMO

OBJECTIVE: To evaluate the ability of the water glass treatment to penetrate zirconia and improve the bond strength of resin cement. MATERIAL AND METHODS: Water glass was applied to zirconia specimens, which were then sintered. The specimens were divided into water-glass-treated and untreated zirconia (control) groups. The surface properties of the water-glass-treated specimens were evaluated using surface roughness and electron probe micro-analyser (EPMA) analysis. A resin cement was used to evaluate the tensile bond strength, with2 and without a silane-containing primer. After 24 h in water storage at 37 °C and thermal cycling, the bond strengths were statistically evaluated with t-test, and the fracture surfaces were observed using SEM. RESULTS: The water glass treatment slightly increased the surface roughness of the zirconia specimens, and the EPMA analysis detected the water glass penetration to be 50 µm below the zirconia surface. The application of primer improved the tensile bond strength in all groups. After 24 h, the water-glass-treated zirconia exhibited a tensile strength of 24.8 ± 5.5 MPa, which was significantly higher than that of the control zirconia (17.6 ± 3.5 MPa) (p < 0.05). After thermal cycling, the water-glass-treated zirconia showed significantly higher tensile strength than the control zirconia. The fracture surface morphology was mainly an adhesive pattern, whereas resin cement residue was occasionally detected on the water-glass-treated zirconia surfaces. CONCLUSION: The water glass treatment resulted in the formation of a stable silica phase on the zirconia surface. This process enabled silane coupling to the zirconia and improved the adhesion of the resin cement.


Assuntos
Colagem Dentária , Vidro , Teste de Materiais , Cimentos de Resina , Silanos , Propriedades de Superfície , Resistência à Tração , Água , Zircônio , Zircônio/química , Cimentos de Resina/química , Silanos/química , Água/química , Colagem Dentária/métodos , Vidro/química , Microscopia Eletrônica de Varredura , Análise do Estresse Dentário
15.
Invest Ophthalmol Vis Sci ; 65(5): 4, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691089

RESUMO

Purpose: To investigate the adhesion of Acanthamoeba to scleral contact lens (ScCL) surface according to lens shape. Methods: Two strains of A. polyphaga (CDC:V062 and ATCC 30461) and one clinical Acanthamoeba isolate, were inoculated onto five contact lens (CL): one first-generation silicone hydrogel (SHCL; lotrafilcon B; adhesion control) containing plasma surface treatment; two ScCL (fluorosilicone acrylate) one containing surface treatment composed of plasma and the other containing plasma with Hydra-PEG, and two CL designed with a flat shape having the same material and surface treatments of the ScCL. Trophozoites that adhered to the lens's surfaces were counted by inverted optical light microscopy. Possible alterations of the lens surface that could predispose amoeba adhesion and Acanthamoeba attached to these lens surfaces were evaluated by scanning electron microscopy (SEM). Results: All strains revealed greater adhesion to the ScCL when compared with the flat lenses (P < 0.001). The clinical isolate and the ATCC 30461 had a higher adhesion (P < 0.001) when compared with the CDC:V062. A rough texture was observed on the surface of the lenses that have been examined by SEM. Also, SEM revealed that the isolates had a rounded appearance on the surface of the ScCL in contrast with an elongated appearance on the surface of the silicone hydrogel. Conclusions: The findings revealed that the curved shape of the ScCL favors amoeba adhesion.


Assuntos
Acanthamoeba , Microscopia Eletrônica de Varredura , Acanthamoeba/fisiologia , Acanthamoeba/ultraestrutura , Esclera , Humanos , Lentes de Contato Hidrofílicas/parasitologia , Adesão Celular/fisiologia , Lentes de Contato/parasitologia , Trofozoítos/ultraestrutura , Trofozoítos/fisiologia , Hidrogéis , Animais
16.
Invest Ophthalmol Vis Sci ; 65(5): 11, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38709524

RESUMO

Purpose: The corneal epithelium is the most highly innervated structure in the body. Previously, we reported a novel event whereby stromal axons fuse with basal epithelial cells, limiting nerve penetration into the epithelium. Although corneal-epithelial nerves undergo changes in sensitivity and distribution throughout life and in response to an obesogenic diet, it is unknown if neuronal-epithelial cell fusion is altered. Here, we sought to determine if neuronal-epithelial cell fusion frequency correlates with obesogenic diet consumption and age. Methods: Corneas were collected from C57BL/6 mice and evaluated for neuronal-epithelial cell fusion frequency using serial block-face scanning electron microscopy. To assess the correlation between diet-induced obesity and fusion frequency, 6-week-old mice were fed either a normal diet or an obesogenic diet for 10 weeks. To assess changes in fusion frequency between young and adult mice under normal dietary conditions, 9- and 24-week-old mice were used. Results: Mice fed a 10-week obesogenic diet showed 87% of central-cornea stromal nerves engaged in fusion compared with only 54% in age-matched controls (16 weeks old). In 9-week-old normal-diet animals, 48% of central-cornea stromal nerves contained fusing axons and increased to 81% at 24 weeks of age. Corneal sensitivity loss correlated with increased body weight and adiposity regardless of age and diet. Conclusions: Neuronal-epithelial cell fusion positively correlates with age and obesogenic diet consumption, and corneal nerve sensitivity loss correlates with increased body weight and adiposity, regardless of age and diet. As such, neuronal-epithelial cell fusion may play a role in corneal nerve density and sensitivity regulation.


Assuntos
Substância Própria , Epitélio Corneano , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Varredura , Obesidade , Animais , Obesidade/patologia , Camundongos , Epitélio Corneano/patologia , Substância Própria/inervação , Substância Própria/patologia , Envelhecimento/fisiologia , Masculino , Modelos Animais de Doenças , Córnea/inervação , Dieta Hiperlipídica/efeitos adversos
17.
Sci Rep ; 14(1): 10292, 2024 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704408

RESUMO

Presenting new molecular and scanning electron microscope (SEM) features, this study gives additional data to the better knowledge of Thaparocleidus vistulensis (Siwak, 1932) (Monopisthocotyla, Ancylodiscoididae), a parasite of the European catfish Silurus glanis Linnaeus, 1758 (Siluriformes, Siluridae) cultured in a commercial fish farm in Hungary. In addition, notes on the early development of sclerotized anchors are also provided. The main morphological difference of T. vistulensis compared to other congeneric species is associated with the male copulatory organ, which exhibits 5-7 loops in the middle of the penis length and a long open V-shaped sclerotized accessory piece, dividing terminally into two parts, securing the terminal part of the penis tube. The present study provides for the first time molecular characterization data based on the 2694 bp long nucleotide sequence of rDNA (ITS1, 5.8S, ITS2, and flanked with partial 18S and partial 28S) submitted in GenBank with the accession number OR916383. A phylogenetic tree based on ITS1 sequences supports a well-defined clade including T. vistulensis, forming a sister group with T. siluri, a species-specific monopisthocotylan parasite to S. glanis. The morphological characterization of T. vistulensis, especially for the male copulatory organ, together with the molecular data in the present study, extends knowledge about this monopisthocotylan species and provides new information for future phylogeny studies.


Assuntos
Peixes-Gato , Microscopia Eletrônica de Varredura , Filogenia , Animais , Masculino , Peixes-Gato/parasitologia , Peixes-Gato/genética , Doenças dos Peixes/parasitologia , Trematódeos/genética , Trematódeos/ultraestrutura , Trematódeos/classificação , DNA Ribossômico/genética
18.
Sci Rep ; 14(1): 10309, 2024 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-38705929

RESUMO

Aplacophoran molluscs are shell-less and have a worm-like body which is covered by biomineralized sclerites. We investigated sclerite crystallography and the sclerite mosaic of the Solenogastres species Dorymenia sarsii, Anamenia gorgonophila, and Simrothiella margaritacea with electron-backscattered-diffraction (EBSD), laser-confocal-microscopy and FE-SEM imaging. The soft tissue of the molluscs is covered by spicule-shaped, aragonitic sclerites. These are sub-parallel to the soft body of the organism. We find, for all three species, that individual sclerites are untwinned aragonite single crystals. For individual sclerites, aragonite c-axis is parallel to the morphological, long axis of the sclerite. Aragonite a- and b-axes are perpendicular to sclerite aragonite c-axis. For the scleritomes of the investigated species we find different sclerite and aragonite crystal arrangement patterns. For the A. gorgonophila scleritome, sclerite assembly is disordered such that sclerites with their morphological, long axis (always the aragonite c-axis) are pointing in many different directions, being, more or less, tangential to cuticle surface. For D. sarsii, the sclerite axes (equal to aragonite c-axes) show a stronger tendency to parallel arrangement, while for S. margaritacea, sclerite and aragonite organization is strongly structured into sequential rows of orthogonally alternating sclerite directions. The different arrangements are well reflected in the structured orientational distributions of aragonite a-, b-, c-axes across the EBSD-mapped parts of the scleritomes. We discuss that morphological and crystallographic preferred orientation (texture) is not generated by competitive growth selection (the crystals are not in contact), but is determined by templating on organic matter of the sclerite-secreting epithelial cells and associated papillae.


Assuntos
Moluscos , Animais , Moluscos/química , Carbonato de Cálcio/química , Cristalografia/métodos , Biomineralização , Exoesqueleto/química , Microscopia Eletrônica de Varredura
19.
Methods Cell Biol ; 187: 139-174, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38705623

RESUMO

Array tomography (AT) allows one to localize sub-cellular components within the structural context of cells in 3D through the imaging of serial sections. Using this technique, the z-resolution can be improved physically by cutting ultra-thin sections. Nevertheless, conventional immunofluorescence staining of those sections is time consuming and requires relatively large amounts of costly antibody solutions. Moreover, epitopes are only readily accessible at the section's surface, leaving the volume of the serial sections unlabeled. Localization of receptors at neuronal synapses in 3D in their native cellular ultrastructural context is important for understanding signaling processes. Here, we present in vivo labeling of receptors via fluorophore-coupled tags in combination with super-resolution AT. We present two workflows where we label receptors at the plasma membrane: first, in vivo labeling via microinjection with a setup consisting of readily available components and self-manufactured microscope table equipment and second, live receptor labeling by using a cell-permeable tag. To take advantage of a near-to-native preservation of tissues for subsequent scanning electron microscopy (SEM), we also apply high-pressure freezing and freeze substitution. The advantages and disadvantages of our workflows are discussed.


Assuntos
Sinapses , Tomografia , Animais , Sinapses/metabolismo , Sinapses/ultraestrutura , Tomografia/métodos , Imageamento Tridimensional/métodos , Coloração e Rotulagem/métodos , Camundongos , Microscopia Eletrônica de Varredura/métodos , Corantes Fluorescentes/química , Microinjeções/métodos , Neurônios/metabolismo , Ratos
20.
Acta Odontol Scand ; 83: 264-272, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709122

RESUMO

PURPOSE: The purpose of the present in vitro study is to investigate and compare the remineralising potential of Moringa Oleifera extract, eggshell, and sodium fluoride varnish on microhardness of artificially demineralised enamel of primary teeth with biomimetic minimally invasive approach following the world paradigm shift towards natural products in paediatric dentistry. MATERIAL AND METHODS: Sample size included 44 primary molars. The mineral content and surface microhardness of all specimens were initially assessed using energy dispersive x-ray examination (EDX) and Vickers microhardness. The specimens were artificially demineralised for 96 h at a temperature of 37°C and then reassessed directly after demineralisation. The demineralised enamel specimens were randomly divided into four groups according to the remineralisation regimen utilised. Group 1: Artificial saliva (control); Group 2: Sodium fluoride varnish; Group 3: Eggshell hydrogel; and Group 4: Moringa Oleifera hydrogel. The specimens were stored for 8 days and then subsequently evaluated using EDX and microhardness assessment by Vickers microhardness test and scanning electron microscope (SEM).  Results: Regarding the microhardness test, there was a significant difference between the Moringa Oleifera group and Eggshell group compared to fluoride varnish (p < 0.05). Regarding EDX analysis, there was a statistically significant difference (p < 0.05) between Moringa Oleifera group and Eggshell group compared to fluoride varnish as the highest values were for Moringa Oleifera and Eggshell. On the other hand, there was no statistically significant difference (p > 0.05) between Moringa Oleifera and Eggshell in both the measurements. CONCLUSION: Moringa Oleifera and Eggshell might be considered as a biomimetic natural material capable of guiding enamel tissue remineralisation in early carious lesion of primary teeth. CLINICAL RELEVANCE: This research demonstrated the capability for early enamel caries to be remineralised using novel materials with a naturally counterpart implicated in biomineralisation as proved to be more effective than traditionally used fluoride varnish in primary teeth.


Assuntos
Casca de Ovo , Hidrogéis , Moringa oleifera , Fluoreto de Sódio , Dente Decíduo , Fluoreto de Sódio/administração & dosagem , Dente Decíduo/efeitos dos fármacos , Casca de Ovo/química , Humanos , Moringa oleifera/química , Remineralização Dentária/métodos , Animais , Técnicas In Vitro , Fluoretos Tópicos/administração & dosagem , Microscopia Eletrônica de Varredura , Esmalte Dentário/efeitos dos fármacos , Dureza/efeitos dos fármacos , Espectrometria por Raios X , Desmineralização do Dente/prevenção & controle , Desmineralização do Dente/tratamento farmacológico
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