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1.
Rev. cuba. estomatol ; 60(1)mar. 2023.
Article in Spanish | LILACS, CUMED | ID: biblio-1521909

ABSTRACT

Introducción: La fijación de las restauraciones indirectas es uno de los pasos más importantes, para conseguir una adecuada retención y sellado de la interfase entre el material restaurador y el diente. Objetivo: Evaluar la resistencia de unión al cizallamiento de diferentes agentes de fijación a dos aleaciones metálicas utilizadas en odontología. Métodos: Estudio experimental in vitro. Cien especímenes de aleaciones de metales base, 50 de níquel-cromo y 50 de níquel-cromo-titanio fueron preparados y divididos de manera aleatoria en 5 grupos. Esta división se realizó acorde con el agente de fijación utilizado: sistema autograbante de dos pasos (Clearfil SE Bond; CSB), sistema adhesivo universal (Single Bond Universal; SBU), cemento resinoso autoadhesivo (Maxcem Elite; ME), ionómero de vidrio (IV) y fosfato de zinc (ZnPO). Posteriormente a la aplicación de cada agente de fijación, los especímenes tratados fueron almacenados en agua destilada por 24 h a 37 ºC y sometidos a un ensayo de resistencia de unión al cizallamiento. Resultados: La resistencia de unión al cizallamiento fue influenciada significativamente por el tipo de agente de fijación (p = 0,002) y el tipo de aleación utilizada (p < 0,001). La resistencia de unión al cizallamiento fue mayor, al utilizar el sistema Clearfil SE Bond, seguida de Single Bond Universal; las diferencias entre Maxcem Elite y el Fosfato de zinc no fueron significativas. Finalmente, el IV no mostró adhesión a ninguna de las aleaciones metálicas utilizadas. Conclusiones: El uso de Clearfil SE Bond aumentó la resistencia de unión de los cementos resinosos a las aleaciones metálicas(AU)


Introduction: The bonding of indirect restorations is one of the most important steps, in order to achieve adequate retention and sealing of the interface between the restorative material and the tooth. Objective: To evaluate the shear bond strength of different bonding agents to two metal alloys used in dentistry. Methods: In vitro experimental study. One hundred specimens of base metal alloys, 50 nickel-chromium and 50 nickel-chromium-titanium were prepared and randomly divided into 5 groups. This division was made according to the bonding agent used: two-step self-etching system (Clearfil SE Bond; CSB), universal adhesive system (Single Bond Universal; SBU), self-adhesive resin cement (Maxcem Elite; ME), glass ionomer (IV) and zinc phosphate (ZnPO). After the application of each bonding agent, the treated specimens were stored in distilled water for 24 hr at 37 ºC and subjected to a shear bond strength test. Results: Shear bond strength was significantly influenced by the type of bonding agent (p = 0.002) and the type of alloy used (p < 0.001). Shear bond strength was highest when using the Clearfil SE Bond system, followed by Single Bond Universal; the differences between Maxcem Elite and Zinc Phosphate were not significant. Finally, IV did not show adhesion to any of the metal alloys used. Conclusions: The use of Clearfil SE Bond increased the bond strength of resinous cements to metallic alloys(AU)


Subject(s)
Humans , Dental Bonding/methods , Dental Cementum
2.
Journal of Pharmaceutical Analysis ; (6): 276-286, 2023.
Article in Chinese | WPRIM | ID: wpr-991142

ABSTRACT

The properties of dry-coated paracetamol particles(fast-dissolving model drug)with carnauba wax particles as the coating agent(dissolution retardant)were investigated.Raman mapping technique was used to non-destructively examine the thickness and homogeneity of coated particles.The results showed that the wax existed in two forms on the surface of the paracetamol particles,forming a porous coating layer:i)whole wax particles on the surface of paracetamol and glued together with other wax surface particles,and ii)deformed wax particles spread on the surface.Regardless of the final particle size fraction(between 100 and 800 μm),the coating thickness had high variability,with average thickness of 5.9±4.2 μm.The ability of carnauba wax to decrease the dissolution rate of paracetamol was confirmed by dissolution of powder and tablet formulations.The dissolution was slower for larger coated particles.Tableting further reduced the dissolution rate,clearly indicating the impact of subsequent formulation processes on the final quality of the product.

3.
Journal of Medical Biomechanics ; (6): E528-E534, 2023.
Article in Chinese | WPRIM | ID: wpr-987981

ABSTRACT

Objective To improve the performance of artificial joint at biological fixed interface by frettingmechanical stimulation. Methods Taking the bonding sample of active rat bone tissues and inactive titanium bead coating as the research object, by using the self-developed fretting mechanical stimulation test device, the effects of mechanical stimulation with different tangential fretting amplitudes on growth promotion and micro-injury of bone tissues at fixed interface were explored, and the mechanism of growth promotion and micro-injury of bonetissues on the surface of titanium bead coating under fretting stimulation was revealed. Results The mechanical stimulation group with 40 μm fretting amplitude showed the maximum interface bonding force between bone tissues and titanium bead coating. The tangential fraction force-displacement curves changed from elliptic shape to linear shape, and the bonding interface was in adhesion area, which was difficult to become loose. The bone tissues had the most complete structure, and the number of tissue cells adhering and growing on the surface of titanium bead coating was the largest, as well as the distribution range was the widest. With the increase of fretting amplitude, the promoting effect of fretting stimulation on bone growth weakened, the bonding strength between bone tissues and titanium bead coating interface gradually decreased, the internal cavity area increased, the number and proliferation activity of tissue cells decreased to varying degrees as well. Conclusions Fretting stimulation with different amplitudes can promote the growth of bone tissue and cause micro-injury at the same time, and the optimal fretting amplitude is 40 μm.

4.
Journal of Medical Biomechanics ; (6): E135-E141, 2023.
Article in Chinese | WPRIM | ID: wpr-987926

ABSTRACT

Objective To investigate the effect of different coating methods on production quality of complex and flexible silicone vascular replicas. Methods Based on models of anterior communicating artery aneurysms, several patient-specific models were made by using spray-coating method and brush-spin-coating method respectively, and two methods for making the same vascular structure were quantitatively compared in terms of thickness growth, circumferential uniformity and light transmittance. Results Brush-spin-coating method was better than spray-coating method in the thickness control and coating uniformity for fabrication of vessels with large curvature, variable diameter and straight tube, and the model had preferably light transmittance and surface smoothness. The relative deviation of thickness by brush-spin-coating method was decreased by 8. 9% , 10. 8% and 16. 9% respectively compared with spray-coating method. Conclusions At present stage, the brush-spin coating method has the advantage of thickness uniformity and light transmittance over the spray-coating method in making silicone phantoms, and it has promising application prospects in fluid mechanics field of in vitro experiment on large vessels.

5.
Digital Chinese Medicine ; (4): 160-169, 2023.
Article in English | WPRIM | ID: wpr-987636

ABSTRACT

@#【Objective】  To study the composition and function of tongue coating (TC) and gastrointestinal tract (GIT) microbiota in participants with yellow-greasy tongue coating (YGTC), and to explore the representative metabolite markers and pathways in this group. 【Methods】  Subjects with YGTC or thin-white tongue coating (TWTC) were recruited from December 1, 2021 to October 30, 2022, and the TC and fecal samples were collected. Samples were subjected to both whole-genome shotgun (WGS), and 16S rRNA gene sequencing. The α-diversity analysis, principal component analysis (PCA), and Spearman correlation analysis were performed for two groups. Ultra-performance liquid chromatography combined with tandem mass spectrometry (UPLC–MS/MS) analysis was used to analyze metabolomics and enrichment of metabolic pathways. 【Results】  The results revealed 20 YGTC participates and 19 TWTC participates. At the genus level, the dominant bacterial species of TC flora and intestinal flora in the two groups were roughly the same, but the relative kurtosis difference was marked, and the abundance of potentially pathogenic bacteria in TC and fecal samples of YGTC subjects was higher. There were 9 down-regulated microorganisms in the TC samples, 26 down-regulated microorganisms, and 6 up-regulated microorganisms in YGTC subjects. The α-diversity analysis indicated that the Chao and abundance-based coverage estimator (ACE) indices of TC bacteria in the YGTC subjects showed a decreasing trend, but the difference was not statistically significant (P > 0.05). The α-diversity of fecal samples and the Chao and ACE indices decreased significantly (P < 0.05). PCA showed that the microflora structure of TC and fecal samples were significantly different between the two groups. Spearman correlation analysis showed that there was no correlation between TC and fecal microorganisms at phyla and genus levels in the same subjects (P > 0.05). The metabolomics results demonstrated that fumarate reductase, V/A ATPase, and phosphatidylethanolamine were increased, and glycerate-3p, UDP-glucose, and quinone oxidoreductase metabolites were decreased in YGTC TC samples. Inosine monophosphate (IMP), uridine monophosphate (UMP), and gamma-aminobutyric acid(GABA) were increased in YGTC fecal samples, while the contents of ribo-5P, histidine, biotin,and cobalamin were decreased. Metabolic pathway analysis indicated that the abundance of the TC and fecal samples of the YGTC subjects was relatively low in various metabolic pathways, including amino acid metabolism, carbohydrate metabolism, nitrogen metabolism, and energy metabolism. 【Conclusion】  Structural and functional changes in TC and GIT microbiota or metabolite markers could be potential biological bases of YGTC formation.

6.
Journal of Prevention and Treatment for Stomatological Diseases ; (12): 473-479, 2023.
Article in Chinese | WPRIM | ID: wpr-965919

ABSTRACT

Objective@# To investigate the effect of cobalt (Co) and calcium-phosphate (Ca/P) doped coating on titanium surfaces and their angiogenic effect.@*Methods @# Microarc oxidation (MAO) was used to prepare Co-Ca/P-doped and Co-doped coatings. Titanium (Ti) sheet without MAO treatment was used as control. Scanning electron microscopy (SEM) was used to observe the surface micromorphology of the coatings. Energy dispersive spectrometry (EDS) was also applied to detect the doped chemicals and their contents. Standard soaking solutions of these coatings were prepared using an endothelial cell medium (ECM) solution for subsequent angiogenesis experiments. Human umbilical vein endothelial cells (HUVECs) were cultured on Matrigel with ECM soaking solutions for 4 h and 8 h. The microvessels were observed under a microscope, and the number of microtubules and their interconnecting nodes were analyzed with Image J software. @*Results@# Co doped and Co-Ca/P-doped coatings were successfully prepared by MAO, which was demonstrated by both SEM observation and EDS analysis. SEM observation showed that irregular crystals of the above chemicals were present on both Co and Co-Ca/P-doped coatings, commonly with a diameter <2 μm. However, more crystals were observed on the Co-Ca/P coatings than on the Co coating, and the distribution of the crystals was more homogenous on the Co-Ca/P coatings. However, only polishing scratches were observed on the Ti sample surface. EDS analysis indicated that in contrast to only Co in the Co coating, Co, Ca and P were doped within the Co-Ca/P coating, and none of the three elements were observed on the Ti plate surface. The number of vascular rings and nodes formed by HUVECs in the extract of the Co-Ca/P group was significantly higher than that of the Co group (P<0.05), and the angiogenic effect of these two components was significantly better than that of the Ti group (P<0.05). @*Conclusion@#The Co-Ca/P coating exhibits good angiogenic properties in vitro and is valuable for the development of new titanium implants with high surface bioactivity.

7.
Chinese Journal of Medical Instrumentation ; (6): 288-293, 2023.
Article in Chinese | WPRIM | ID: wpr-982230

ABSTRACT

Blood compatibility is the main restriction of blood-contacting medical devices in clinical application, especially long-term blood-contacting medical devices will stimulate the immune defense mechanism of the host, resulting in thrombosis. Heparin anticoagulant coating links heparin molecules to the surface of medical device product materials, improves the compatibility between the material surface interface and the body, and reduces the host immune defense reactions. This study reviews the structure and biological properties of heparin, the market application status of heparin-coated medical products, the insufficiency and improvement of heparin coating, which can provide a reference for the application research of blood contact medical devices.


Subject(s)
Humans , Heparin/chemistry , Anticoagulants/chemistry , Thrombosis , Coated Materials, Biocompatible/chemistry , Surface Properties
8.
Journal of Peking University(Health Sciences) ; (6): 94-100, 2023.
Article in Chinese | WPRIM | ID: wpr-971279

ABSTRACT

OBJECTIVE@#To study microstructure, friction and wear behaviors of silicon-lithium spray coating on the surface of zirconia ceramics and to preliminarily evaluate its esthetic so as to provide support and guidance for the clinical application.@*METHODS@#Zirconia ceramic specimens were randomly divided into three groups: coating group (two subgroups), polishing group (two subgroups), and glazing group (four subgroups), with 10 samples in each subgroup. The two subgroups of coating group were the zirconia ceramics with the untreated and preliminary polishing surfaces sprayed with silicon-lithium coating, respectively. The two subgroups of polishing group were preliminary polishing and fine polishing of zirconia ceramics, respectively. The four subgroups of glazing group were preliminarily polished zirconia ceramics glazed with Biomic and Stain/Glaze products, respectively; and untreated zirconia ceramics glazed with Biomic and Stain/Glaze products, respectively. The above 8 subgroups of zirconia ceramic specimens were used as friction pairs with 80 steatite ceramics for 50 000 chewing cycles under 50 N vertical load and artificial saliva lubrication using chewing simulation. Scanning electron microscope was used to observe the microstructure of the surface and section of the coating group, and the thickness of the coating and glazing were measured. The linear roughness of the coating and polishing groups was mea-sured using a laser confocal scanning microscope. Vickers hardness was measured using a microhardness tester and the esthetic of zirconia ceramic full crown sprayed with silicon-lithium coating was preliminarily evaluated. White light interferometer was used to measure the width, the maximum depth and the volume of the wear scars of each group, and the wear depth of steatite ceramics and wear rate of zirconia ceramic specimens were calculated. Kruskal-Wallis nonparametric test and Dunn's multiple comparisons test were used to analyze the wear depth of each group (α=0.05).@*RESULTS@#The microstructures of the silica-lithium spray coatings on the untreated and preliminarily polished zirconia ceramic surfaces showed the protruding defects, and the line roughness of coating group was larger than that of the polishing group. The median thickness of the silica-lithium spray coating on the preliminarily polished zirconia ceramic was 13.0 μm (interquartile range, IQR: 11.6, 17.9), while that of the silica-lithium spray coating on the untreated zirconia ceramic was 4.4 μm (IQR: 4.1, 4.7). The Vickers hardness and wear rate of the coating group were between the polishing group and the glazing group. The wear depths of the wear scars of steatite ceramics were the glazing group, coating group, and polishing group in descending order, and there was statistically significant difference between glazing and polishing groups (P < 0.05). With the increase of polishing procedure, the wear depth of steatite ceramics decreased in each subgroups. The orders of maximum depth and volume of wear scars of zirconia ceramic were the glazing group, coating group, and polishing group in descending order, and there was statistically significant difference in the maximum depth of wear scars between glazing and polishing groups (P < 0.05).@*CONCLUSION@#The silica-lithium spray coating on the zirconia ceramic, can be used as a new method for zirconia ceramic surface treatment, because it can increase the esthetic of zirconia ceramics compared with polishing and reduce the wear of steatite ceramics compared with glazing.


Subject(s)
Humans , Silicon , Materials Testing , Friction , Lithium , Cicatrix , Surface Properties , Silicon Dioxide , Zirconium/chemistry , Ceramics , Dental Porcelain
9.
Hig. Aliment. (Online) ; 37(297): e1122, jul.-dez. 2023. ilus, tab
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1531976

ABSTRACT

Várias pesquisas mostram o interesse na aplicação de materiais de revestimento na superfície de cascas de ovos para preservar a qualidade interior dos ovos, bem como para prolongar sua vida útil. No presente trabalho verificou-se a qualidade interna de 100 ovos galinhas para o consumo. Os ovos foram revestidos externamente na casca com tratamento de óleo mineral e timol 10%, e um grupo controle, que não sofreu nenhum tipo de tratamento. Um total de 10 ovos de cada grupo (controle e tratado) foram avaliados no dia 7, 14, 21 dias de armazenamento em relação aos seus parâmetros internos de qualidade. Os parâmetros físico-químicos de qualidade dos ovos avaliados foram Perda de peso dos ovos (g), Porcentagem da gema (%), Porcentagem do albúmen (%), Índice de gema, pH do Albúmen, pH da gema e Unidades Haugh (UH). Foi observada diminuição da qualidade interna dos ovos durante os períodos de armazenamento principalmente no grupo controle. Os ovos do grupo controle, que não receberam nenhum tipo de revestimento apresentaram a maior perda de peso e os valores da unidade Haugh diminuíram ao longo do armazenamento, o que não foi observado nos dois grupos tratados. A unidade Haugh dos grupos tratados não apresentaram diferenças significativas entre si. Concluiu-se que os ovos tratados com óleo mineral e timol a 10%, o revestimento da casca contribuiu para a preservação dos ovos mantendo positivamente a qualidade interna dos ovos ao longo do período de estocagem, o que pode contribuir para o aumento da vida de prateleira de ovos.


Several researchers show interest in the application of coating materials on the surface of eggshells to preserve the interior quality of the eggs, as well as to prolong their shelf life. In the present work, the internal quality of 100 chicken eggs for consumption was verified. The eggs were coated externally in the shell with mineral oil and 10% thymol treatment, and a control group did not undergo any type of treatment. a total of 10 eggs from each group (control and treated) were evaluated on day 7, 14, 21 of storage in relation to their internal quality parameters. The physicochemical parameters of egg quality evaluated were egg weight loss (g), yolk percentage (%), albumen percentage (%), yolk index, albumen pH, yolk ph and haugh units (uh). decreased internal egg quality was observed during storage periods, mainly in the control group. The eggs in the control group, which did not receive any kind of coating, showed the greatest weight loss and the haugh unit values decreased during storage, which was not observed in the two treated groups. The haugh unit of the treated groups did not show significant differences between them. It was concluded that in eggs treated with mineral oil and 10% thymol, the shell coating contributed to the preservation of the eggs, positively maintaining the internal quality of the eggs throughout the storage period, which may contribute to an increase in shelf life of eggs.


Subject(s)
Chickens , Egg Shell , Eggs , Date of Validity of Products , Thymol , Mineral Oil
10.
Shanghai Journal of Preventive Medicine ; (12): 825-830, 2023.
Article in Chinese | WPRIM | ID: wpr-997036

ABSTRACT

ObjectiveTo evaluate the caries prevention effect of different fluoride application frequencies in 3-year-old children with active caries. MethodsA total of 337 3-year-old children with dental caries from 12 kindergartens in Changning District of Shanghai were divided into three groups: group 1 received fluoride application once every three months, group 2 received fluoride application once every six months, and the control group received no fluoride application. At baseline, parents completed a questionnaire survey, and oral examinations were conducted at baseline, 7 months, and 16 months after the fluoride intervention to assess the incidence of new dental caries, new dmft, and new dmfs of children. Multivariate logistic regression analysis was used to analyze the relationship between fluoride application and new dental caries, with new dental caries as the dependent variable and local fluoride application, child's gender, age in months, parents' highest education level, frequency of sugary intake (desserts, candies, sweet beverages), age of toothbrushing initiation, frequency of daily toothbrushing, use of fluoride toothpaste, parental assistance in child’s toothbrushing, and daily use of dental floss as the independent variables. ResultsThere were no significant differences in baseline general conditions and oral health behaviors among group 1 (121 cases), group 2 (123 cases) and the control group (93 cases) (all P>0.05). After 16 months' intervention, three children were lost to follow-up due to transferring schools. The new caries rates of group 1 (120 cases), group 2 (121 cases) and the control group (93 cases) were 5.83%, 24.79% and 52.69%, respectively. The incidence of new caries was significantly lower in group 1 compared to group 2 and the control group (P<0.001), and it was also significantly lower in group 2 compared to the control group (P<0.001). The newly-increased caries of group 1, group 2 and the non-fluoride control group were all 0.12 0.52, 0.36 0.68 and 1.16 1.39, respectively. The mean increment of new caries was lower in group 1 compared to group 2 (P=0.040) and the non-fluoride control group (P<0.001), and it was lower in group 2 compared to the non-fluoride control group (P<0.001). After adjusting for factors such as gender, parents' education level and child's oral health behaviors by multivariate logistic regression, the results showed that fluoride application once every three months could significantly reduce the risk of dental caries (OR=0.04, P<0.001). ConclusionLocal use of fluoride has a certain effect on the prevention and treatment of dental caries in children with active caries. Fluoride application once every three months effectively reduces the incidence of new caries and slows down the progression of caries lesions. It is suggested that local application of fluoride should be implemented once every three months for children with active caries.

11.
Chinese Journal of Orthopaedic Trauma ; (12): 260-266, 2023.
Article in Chinese | WPRIM | ID: wpr-992706

ABSTRACT

Objective:To investigate the antibacterial and osteogenic properties of biomimetic mineralized iodine-loaded coating with micro-nano topography on the surface of bone implants.Methods:After the fiber network structure of sodium hydrogen titanate was constructed by alkali thermal reaction on the surface of Ti6Al4V (noted as AT), it was biomimetically mineralized in the modified simulated body fluid to form a micro-nano topology with high specific surface area (noted as AT-CaP), and finally loaded with PVPI to construct a novel antibacterial osseointegration coating (noted as AT-CaP-PVPI). The study was conducted in AT, AT-CaP, and AT-CaP-PVPI groups, in each of which 3 parallel experiments were performed. The morphology and colony counting of Staphylococcus aureus on the coating surface were observed to detect the in vitro antibacterial performance of the coating. Fifteen male SD rats were randomly divided into 3 groups ( n=5): AT, AT-CaP, and AT-CaP-PVPI. After intramedullary injection of Staphylococcus aureus into the lower end of the femur in the SD rats, titanium rods coated with AT, AT-CaP, and AT-CaP-PVPI were inserted into the marrow cavity. The osteogenesis, volume ratio of new bone mass and number of trabeculae on the surface of the femoral implants were compared between the 3 groups 4 weeks after operation. Results:In AT and AT-CaP groups, a large number of bacteria grew in their inherent elliptical or spherical shape on the implant surface and a large number of colonies were seen on the plate; in AT-CaP-PVPI group, the bacteria on the coating surface exhibited membrane deformation and depression, some of them were completely broken and dissolved, and a large number died. There was almost no new bone formation around the implants in AT group; new bone scattered around the implants with discontinuous distribution in AT-CaP group; a great amount of new bone was seen around the implants with even distribution but no signs of infection in AT-CaP-PVPI group. The volume ratio of new bone mass and the number of trabeculae on the implant surface in AT-CaP-PVPI group were 0.453±0.206 and 6.055±0.536, respectively, significantly higher than those in AT group (0.046±0.028 and 1.667±1.249) and AT-CaP group (0.188±0.052 and 3.804±0.889) ( P<0.05). Conclusion:Biomimetic mineralized iodine-loaded coating with micro-nano topography on the surface of bone implants shows good antibacterial and osteogenic properties.

12.
Acta Pharmaceutica Sinica B ; (6): 852-862, 2023.
Article in English | WPRIM | ID: wpr-971722

ABSTRACT

Cell membrane camouflaged nanoparticles have been widely used in the field of drug leads discovery attribute to their unique biointerface targeting function. However, random orientation of cell membrane coating does not guarantee effective and appropriate binding of drugs to specific sites, especially when applied to intracellular regions of transmembrane proteins. Bioorthogonal reactions have been rapidly developed as a specific and reliable method for cell membrane functionalization without disturbing living biosystem. Herein, inside-out cell membrane camouflaged magnetic nanoparticles (IOCMMNPs) were accurately constructed via bioorthogonal reactions to screen small molecule inhibitors targeting intracellular tyrosine kinase domain of vascular endothelial growth factor recptor-2. Azide functionalized cell membrane acted as a platform for specific covalently coupling with alkynyl functionalized magnetic Fe3O4 nanoparticles to prepare IOCMMNPs. The inside-out orientation of cell membrane was successfully verified by immunogold staining and sialic acid quantification assay. Ultimately, two compounds, senkyunolide A and ligustilidel, were successfully captured, and their potential antiproliferative activities were further testified by pharmacological experiments. It is anticipated that the proposed inside-out cell membrane coating strategy endows tremendous versatility for engineering cell membrane camouflaged nanoparticles and promotes the development of drug leads discovery platforms.

13.
Acta Pharmaceutica Sinica B ; (6): 327-343, 2023.
Article in English | WPRIM | ID: wpr-971700

ABSTRACT

Extended circulation of anticancer nanodrugs in blood stream is essential for their clinical applications. However, administered nanoparticles are rapidly sequestered and cleared by cells of the mononuclear phagocyte system (MPS). In this study, we developed a biomimetic nanosystem that is able to efficiently escape MPS and target tumor tissues. The fabricated nanoparticles (TM-CQ/NPs) were coated with fibroblast cell membrane expressing tumor necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL). Coating with this functionalized membrane reduced the endocytosis of nanoparticles by macrophages, but increased the nanoparticle uptake in tumor cells. Importantly, this membrane coating specifically induced tumor cell apoptosis via the interaction of TRAIL and its cognate death receptors. Meanwhile, the encapsulated chloroquine (CQ) further suppressed the uptake of nanoparticles by macrophages, and synergized with TRAIL to induce tumor cell apoptosis. The vigorous antitumor efficacy in two mice tumor models confirmed our nanosystem was an effective approach to address the MPS challenge for cancer therapy. Together, our TM-CQ/NPs nanosystem provides a feasible approach to precisely target tumor tissues and improve anticancer efficacy.

14.
Vitae (Medellín) ; 29(3): 1-12, 2022-08-18. Ilustraciones
Article in English | LILACS, COLNAL | ID: biblio-1393178

ABSTRACT

Background: This research was motivated by the complaints of tomato farmers about their crops that quickly rotted before being sold, as well as the many research results (raw materials and methods) that edible coating films could not be applied optimally. Objectives: The research was a practical recommendation by comparing the effectiveness of raw materials (polysaccharides, proteins, and lipids) with the dipping and spray methods. Materials and methods used in the comparison process were the application of Structural Equation Modeling (SEM) with the Partial Least Square (PLS) approach. Results: Dipping has a strong effect (f2 ≥ 0.35; p<0.05), while spray had a moderate effect (f2: 0.15-0.35; p<0.05). Thus, the role of dipping as a mediator was more dominant than spray. Compared to proteins and lipids, polysaccharides had the best effectiveness (ß:0.460-0.584; f2: 0.15-0.35; p<0.05). Conclusion: the three ingredients improved the quality of tomatoes, and the dipping method was easier to apply by farmers than the spray method, which had many obstacles in its application


Antecedentes: esta investigación está motivada por las quejas de los productores de tomate sobre sus cultivos que se pudren rápidamente antes de ser vendidos, así como por los muchos resultados de la investigación (materias primas y métodos) de que las películas de recubrimiento comestibles no se pudieron aplicar de manera óptima. Objetivos: La investigación consiste en recomendaciones prácticas mediante la comparación de la eficacia de las materias primas (polisacáridos, proteínas y lípidos) con los métodos de inmersión y aspersión. Métodos: El método utilizado en el proceso de comparación es la aplicación del modelo de ecuaciones estructurales (SEM) con el enfoque de mínimos cuadrados parciales (PLS). Resultados: La inmersión tiene un efecto fuerte (f2 ≥ 0,35; p<0,05), mientras que la pulverización tiene un efecto moderado (f2: 0,15-0,35; p<0,05). Por lo tanto, el papel de la inmersión como mediador es más dominante que el del rociado. Los polisacáridos tienen la mejor eficacia (ß:0,460-0,584; f2: 0,15-0,35; p<0,05) en comparación con las proteínas y los lípidos. Conclusión: es que los tres ingredientes pueden mejorar la calidad de los tomates, y el método de inmersión es más fácil de aplicar por los agricultores que el método de aspersión, que tiene muchos obstáculos en su aplicación


Subject(s)
Humans , Food Quality , Solanum lycopersicum , Immersion , Polysaccharides/administration & dosage , Effectiveness , Proteins/administration & dosage , Latent Class Analysis , Lipids/administration & dosage
15.
Braz. dent. j ; 33(1): 1-12, jan.-fev. 2022. graf
Article in English | LILACS-Express | LILACS, BBO | ID: biblio-1364486

ABSTRACT

Abstract Dental implants made of titanium (Ti) material is recognized as the leading treatment option for edentulous patients' rehabilitation, showing a high success rate and clinical longevity. However, dental implant surface acts as a platform for microbial adhesion and accumulation once exposed to the oral cavity. Biofilm formation on implant surfaces has been considered the main etiologic factor to induce inflammatory diseases, known as peri-implant mucositis and peri-implantitis; the latter being recognized as the key reason for late dental implant failure. Different factors, such as biofilm matrix production, source of carbohydrate exposure, and cross-kingdom interactions, have encouraged increased microbial accumulation on dental implants, leading to a microbiological community shift from a healthy to a pathogenic state, increasing inflammation and favoring tissue damage. These factors combined with the spatial organization of biofilms, reduced antimicrobial susceptibility, complex microbiological composition, and the irregular topography of implants hamper biofilm control and microbial killing. In spite of the well-known etiology, there is still no consensus regarding the best clinical protocol to control microbial accumulation on dental implant surfaces and treat peri-implant disease. In this sense, different coatings and Ti surface treatments have been proposed in order to reduce microbial loads and control polymicrobial infections on implantable devices. Therefore, this critical review aims to discuss the current evidence on biofilm accumulation on dental implants and central factors related to the pathogenesis process of implant-related infections. Moreover, the potential surface modifications with anti-biofilm properties for dental implant devices is discussed to shed light on further promising strategies to control peri-implantitis.


Resumo Implantes dentários em titânio (Ti) são reconhecidos como principal modalidade terapêutica para a reabilitação oral de pacientes edêntulos, demonstrando uma alta taxa de sucesso e longevidade clínica. No entanto, após inserção no ambiente bucal, os implantes dentários agem como substrato para adesão e acúmulo microbiano. A formação de biofilmes em implantes dentários tem sido considerada o principal fator etiológico para induzir doenças inflamatórias conhecidas como mucosite peri-implantar e peri-implantite, sendo está última reconhecida como principal razão para falha tardia dos implantes dentários. Diferentes fatores têm sido atribuídos por promover o acúmulo microbiano em implantes dentários, levando a uma mudança microbiológica e favorecendo o dano tecidual, como a matriz do biofilme, exposição a carboidratos e interação entre reinos. Esses fatores combinados com a organização espacial de biofilmes, reduzida suscetibilidade microbiana, complexa composição microbiológica e a superfície irregular dos implantes dificultam o controle do biofilme e a morte microbiana. Apesar da etiologia bem conhecida, ainda não há consenso sobre o melhor protocolo clínico para controlar o acúmulo microbiano nas superfícies dos implantes dentários e tratar a doença peri-implantar. Nesse sentido, diferentes coberturas e tratamentos de superfície no Ti têm sido desenvolvidos objetivando a redução dos níveis microbianos e o controle das infecções polimicrobianas em implantes. Portanto, essa revisão crítica objetiva discutir a atual evidência em relação ao acúmulo de biofilmes em implantes dentários e fatores chave relacionados ao processo patogênico das infecções peri-implantares. Além disso, o potencial de alterações de superfícies com propriedades antimicrobianas para implantes dentários é discutido para ressaltar futuras estratégias promissoras no controle da peri-implantite.

16.
International Journal of Biomedical Engineering ; (6): 104-111, 2022.
Article in Chinese | WPRIM | ID: wpr-954200

ABSTRACT

Objective:To investigate the antimicrobial properties of copper-loaded coatings on the surface of ureteral stents and their biocompatibility in order to determine the most suitable level of copper loading.Methods:Copper-loaded PDA coatings with different copper contents were constructed on the surface of polyurethane (PU) stents using polydopamine (PDA) and dimethylaminomethylborane (DMAB). The antibacterial property of the coating against Escherichia coli and Staphylococcus aureus was investigated by the plate counting method. The bacterial adhesion on the coating surface was studied by scanning electron microscopy. Using the live/dead evaluation, microbes were stained and observed by a fluorescence microscope. The biocompatibility of the copper-loaded coatings was detected by a cell proliferation assay incubated with L929 cells.Results:The antibacterial rates of the copper-loaded samples exceeded 90% after incubation with E. coli and S. aureus for 24 h, respectively, and the antibacterial performance increased with the increase of copper content in the coating. The amount of bacteria adhered to the surface of the copper-loaded samples was significantly lower, and most of them were dead bacteria. When the copper content in the coating preparation solution used was 0.25~1 g/L, the cell proliferation rate on the surface of the copper-loaded coating was higher than 80% and the material was not cytotoxic.Conclusions:A copper-loaded PDA coating with excellent antibacterial properties and good biocompatibility can be prepared with a copper content of 1 g/L in the coating preparation solution, forming a potential solution for the preparation of ureteral stent coatings.

17.
Braz. J. Pharm. Sci. (Online) ; 58: e19106, 2022. tab, graf
Article in English | LILACS | ID: biblio-1374575

ABSTRACT

Abstract In this work, polystyrene-b-poly (acrylic acid) (PS-b-PAA) nanovesicles were coated by modified chitosans aiming at studying its physicochemical parameters. The chitosan (CS) was chemically modified to add hydrophilic and/or hydrophobic groups, obtaining three modified chitosans. The PS-b-PAA nanovesicles were obtained by organic (1,4-dioxane) cosolvent method in water, resulting in nanovesicles with less than 150 nm of diameter (polydispersibility index - PDI at 90° = 0.106), measured by dynamic light scattering (DLS) and transmission electron microscopy (TEM), and negative zeta potential (-37.5 ± 3.2 mV), allowing the coating of its surface with oppositely charged polysaccharides, such as the CS and the modified chitosans. The coating process was made by mixing the colloidal suspensions with the CS and the modified chitosans at specific ENT#091;CS-xENT#093;/ENT#091;PS-b-PAAENT#093; ratios (0.001 to 1.0 wt %) and measuring the change in size and surface charge by DLS and zeta potential. Upon reaching maximum adsorption, the zeta potential parameter was positively stabilized (+26.7 ± 4.1 mV) with a hydrodynamic diameter slightly longer (< 200 nm of diameter). The encapsulation efficiency (EE) of minoxidil, quantified by capillary electrophoresis, was 50.7%, confirming their potential as drug delivery carriers and the coating process showed the possibility of controlling the surface charge nature of these nanovesicles


Subject(s)
Chitosan/metabolism , Minoxidil/analogs & derivatives , Microscopy, Electron, Transmission/methods , Efficiency/classification , Dynamic Light Scattering/instrumentation , Methods
18.
China Pharmacy ; (12): 891-896, 2022.
Article in Chinese | WPRIM | ID: wpr-923199

ABSTRACT

Enteric-soluble soft capsule is a kind of new preparation that does not disintegrate in the stomach ,but releases rapidly in the intestinal tract to play a pharmacodynamic role. It has the unique advantages of improving drug stability ,reducing drug irritation ,delivering drugs directionally to the intestinal tract ,and prolonging drug action time. In this paper ,the decomposition and release mechanism ,application advantages ,classification of enteric-soluble coating materials and preparation methods of enteric-soluble soft capsule are sorted and summarized ,in order to provide reference for further development of this type of preparation.

19.
Chinese Journal of Medical Instrumentation ; (6): 191-194, 2022.
Article in Chinese | WPRIM | ID: wpr-928886

ABSTRACT

Lubrication coating is widely used to reduce the friction between the interventional devices and the blood vessels, improves the surface biocompatibility of the interventional device, and also brings the coating stability problems and related risks. This paper describes the coating-related content from the equipment description, performance verification, technical requirements, etc., to reduce the risk of the coating to an acceptable level.


Subject(s)
Catheters , Coated Materials, Biocompatible , Friction , Lubrication
20.
Odontol. vital ; (35)dic. 2021.
Article in Spanish | LILACS, SaludCR | ID: biblio-1386457

ABSTRACT

Resumen La halitosis es considerada como una condición anómala frecuente en la salud bucal y se define como un olor desagradable que emite la cavidad oral, nariz, vías respiratorias o aparato digestivo. Objetivo: Determinar la prevalencia de halitosis y su relación con los factores asociados como: higiene oral, caries, placa lingual, tipo de respiración, edad y sexo en niños de 5 a 12 años que asisten a la Escuela Giordano Bruno, de la Provincia de Pichincha - Ecuador. Materiales y métodos: Estudio observacional, descriptivo, transversal realizado en una población de 178 estudiantes de 5 a 12 años, la muestra fue de 122 niños seleccionados mediante un muestreo probabilístico. Se solicitó el consentimiento informado para participar en el estudio. La prevalencia de halitosis se evaluó con un monitor que detecta compuestos volátiles de sulfuro. Los factores asociados se midieron por medio del IHOS, el índice de lengua saburral de Winkel, la prueba con el espejo bucal y el índice ceo-d y CPO-D. Los datos se analizaron con la prueba de Chi cuadrado con un valor de significación de 0,05 y un Análisis de Regresión Logística Binaria. Resultados: La prevalencia de halitosis fue del 50% en los niños y se relacionó con saburralingual, higiene bucal, edad y sexo (p<0,05), pero no hubo asociación entre la halitosis, el tipo de respiración y la presencia de caries dental. Los niños que presentan saburra lingual tienen 177 veces mayor riesgo de presentar halitosis mientras que los que muestran una higiene bucal regular tienen 205 veces más riesgo de presentar halitosis. Conclusión: La prevalencia de halitosis en niños es alta y los principales factores de riesgo son la saburra lingual y la higiene bucal regular.


Abstract Halitosis is considered a frequent anomaly in oral health that is defined as an unpleasant odor that emits from the oral cavity, nose, respiratory tract or digestive system. Objective: To determine the prevalence of halitosis and its relationship with associated factors such as: oral hygiene, tooth decay, tongue plaque, type of breathing, age and sex in children aged 5 to 12 years who attend the Giordano Bruno School of the Province of Pichincha - Ecuador. Materials and methods: Observational, descriptive, cross-sectional study carried out in a population of 178 students aged 5 to 12 years, the sample consisted of 122 children selected through probability sampling. Informed consent was requested to participate in the study. The prevalence of halitosis was evaluated with a monitor that detects volatile sulfur compounds and the associated factors were measured by means of the IHOS, the Winkel coated tongue index, the oral mirror test and the ceo-d and CPO-D index. The data were analyzed with the Chi square test with a significance value of 0.05 and a Binary Logistic Regression Analysis. Results: The prevalence of halitosis was 50% in children and it was related to tongue coating, oral hygiene, age, and sex (p <0.05), there was no association between halitosis, type of respiration and the presence of dental caries. Children with tongue coating have a 177 times greater risk of halitosis, while children with regular oral hygiene have a 205 times greater risk of halitosis. Conclusion: The prevalence of halitosis in children is high and the main risk factors are tongue coating and regular oral hygiene.


Subject(s)
Humans , Male , Female , Child , Oral Hygiene , Dental Caries , Halitosis/diagnosis , Ecuador
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