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1.
Journal of Public Health and Preventive Medicine ; (6): 17-20, 2024.
Artículo en Chino | WPRIM | ID: wpr-1016404

RESUMEN

Objectives To analyze the spatial and temporal aggregation of multidrug resistant pulmonary tuberculosis (MDR-TB) incidence in Nanning at the township / street scale from 2017 to 2021, to explore the spatial and temporal characteristics of the spread of MDR-TB in Nanning, and to provide a scientific reference basis for the health administrative departments to achieve the precise implementation of MDR-TB prevention and control. Methods Based on the data of MDR-TB cases in Nanning from 2017 to 2021, the spatial-temporal scanning analysis software SaTScan v9.7 was used to retrospectively detect and analyze the areas where MDR-TB cases gathered. Results Through simple spatial scanning analysis, it was found that there were three first-class aggregation areas (the aggregation center was Fujiayuan Street, Jiangnan District, 2017, Xinyang Street, Xixiangtang District, 2019, and Zhonghe Town, Yongning District, 2020), and one second-class aggregation area (the aggregation center was Jinchai Town, Mashan County, 2020). Simple time scanning showed that the clustering occurred from May 2019 to December 2020. Temporal and spatial aggregation analysis showed that Xinyang Street in Xixiangtang District was the center of the first-class aggregation area, Zhonghe Town in Yongning District was the center of the second-class aggregation area, and Jinchai Town in Mashan County was the center of the third-class aggregation area. Conclusion The multidrug resistant pulmonary tuberculosis epidemic in Nanning is distributed in an aggregated manner, especially in Xinyang Street, Xixiangtang District, which has the highest spatial and temporal aggregation. It is necessary to focus on and take regional prevention and control measures to control the epidemic.

2.
Journal of Prevention and Treatment for Stomatological Diseases ; (12): 216-222, 2024.
Artículo en Chino | WPRIM | ID: wpr-1006866

RESUMEN

Objective@#To explore an accurate method to obtain an intraoral model of patients with specific limited mouth opening (microstomia) due to systemic scleroderma.@*Methods@#This study followed medical ethics, and informed consent has been obtained from patients. A case of Ken's Type I mandibular dentition defect scleroderma with limited mouth opening was addressed with digital technology as the leading method combined with the traditional impression method of segmental impression. Individual trays were made based on the patient's left and right mandibular dentition, and segmented molds were obtained. Simultaneously, intraoral scanning was performed to obtain the morphological data of both the soft and hard tissues of the upper and lower mandibles. After each part of the model was obtained, the mandibular model was scanned and digitally aligned to form the final denture model, and the final removable partial denture was designed and made by computer aided design/computer aided manufacturing (CAD/CAM) technology. At the same time, combined with the literature, the diagnosis and treatment of removable partial denture in patients with limited mouth opening were retrospectively analyzed.@*Results@#The denture was well retained and achieved a good repair effect. The patients expressed satisfaction with the mastication efficiency and other functions of the denture. The findings of the literature review show that the integration of digital technology with the traditional impression method, along with computer fitting, can accurately obtain the patient's oral model and facilitate successful follow-up repairs. However, when the anterior mandibular dentition of the patient is absent, the margin of error is increased in this procedure, which deserves further exploration.@*Conclusion@#Utilizing digital technology as the leading method, combined with the traditional impression method of segmental impression, for the repair of dental defects in patients with limited mouth opening, has proven to be effective. Thus, patients report a positive medical experience with high satisfaction, indicating that this approach is worthy of clinical promotion.

3.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 175-182, 2024.
Artículo en Chino | WPRIM | ID: wpr-1005267

RESUMEN

ObjectiveTo explore the scientific connotation of fried charcoal survivability of Lonicerae Japonicae Flos(LJF) by analyzing the correlation between the color change and the intrinsic components during the processing of LJF Carbonisata(LJFC), and taking pH, charcoal adsorption and microscopic characteristics as indexes. MethodLJFC samples with different degrees of processing were prepared according to the stir-frying time of 0.0, 1.5, 3.0, 4.5, 6.0, 7.5, 9.0, 10.5 min(numbered S1-S8), and the contents of gallic acid, chlorogenic acid, cryptochlorogenic acid, rutin, luteoloside, isochlorogenic acid A and isochlorogenic acid C were determined by high performance liquid chromatography(HPLC), and the L*(brightness), a*(red-greenness) and b*(yellow-blueness) of LJFC samples with different degrees of processing were determined by spectrophotometer, and the correlation analysis and principal component analysis(PCA) between the contents of seven representative components and the color of the samples were carried out by SPSS 26. 0 and SIMCA-P 14.1. Then pH, adsorption force and characteristic structure of different samples of LJFC were detected and the processing pattern of LJFC was analyzed. ResultThe results of quantitative analysis revealed that the contents of luteoloside, rutin, chlorogenic acid and isochlorogenic acid A gradually decreased, and the contents of cryptochlorogenic acid, isochlorogenic acid C and gallic acid firstly increased and then decreased. The L* and b* of the sample powders decreased, and a* showed a trend of increasing and then decreasing. The L* and b* were positively correlated with the contents of chlorogenic acid, rutin, luteoloside, isochlorogenic acid A, b* was positively correlated with the content of gallic acid, and a* was positively correlated with the contents of cryptochlorogenic acid and isochlorogenic acid C. PCA revealed that samples could be clearly divided into 3 groups, S1-S2 as one group, S3-S5 as one group, and S6-S8 as one group, with S3 having the highest score. The results of regression analysis showed that only isochlorogenic acid C could be used to predict the contents of components by colorimetric values combined with regression equations. Physicochemical analysis showed that pH of LJFC increased with the increase of degree of charcoal stir-frying, while adsorption force showed a tendency of increasing and then decreasing, with the highest adsorption force in the S5 sample, and the non-glandular hairs, calcium oxalate clusters and pollen grains had a varying degree of decreasing with the deepening of processing degree, and the microstructures of S6-S8 samples were obviously charred with pollen grains almost invisible. ConclusionThe changes in chemical composition and color characteristics of LJFC during the processing have certain correlations, combined with the changes in physicochemical properties, S5 sample is found to be the optimal processed products, which can provide a reference for the processing standardization and quality evaluation of LJFC, and enrich the scientific connotation of fried charcoal survivability of LJF.

4.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469374

RESUMEN

Abstract The present study aimed to investigate the beneficial of prepared black rice anthocyanins nano-composite (An-AgNps) against hepatotoxicity induced by methotrexate (MTX) in rats. Anthocyanins nano-composite was prepared by silver as the metallic ion reduction and were characterized by IR and SEM. The rats in our experiment were divided into five groups. Serum lipid profile, serum transaminases (ALT and AST), ALP, LDH, TBA, GSH and SOD were examined. The results show that SEM of An-AgNps has average particle size from 70 to 130nm. In the group treated with MTX; TC, TG, LDL-c, ALT, AST, ALP, LDH and TBA levels were significantly (P0.05) increased than NC, while, HDL-c, SOD and GSH levels were significantly (P0.05) decreased. On the other hand, An-AgNps + MTX treated groups were reversed the levels of all biomarkers similar to NC. In conclusion, the results show that An-AgNps has a protective effect on MTX-induced hepatotoxicity and oxidative stress.


Resumo O presente estudo teve como objetivo investigar o benefício de nanocompósito de antocianinas de arroz preto preparado (An-AgNps) contra a hepatotoxicidade induzida por metotrexato (MTX) em ratos. O nanocompósito de antocianinas foi preparado a partir da prata por meio da redução do íon metálico e caracterizado por IR e SEM. Os ratos em nosso experimento foram divididos em cinco grupos, e foram examinados o perfil lipídico sérico, as transaminases séricas (ALT e AST), ALP, LDH, TBA, GSH e SOD. Os resultados mostram que SEM de An-AgNps tem tamanho médio de partícula de 70 a 130 nm. No grupo tratado com MTX, os níveis de TC, TG, LDL-c, ALT, AST, ALP, LDH e TBA aumentaram significativamente (P 0,05) do que NC, enquanto os níveis de HDL-c, SOD e GSH diminuíram significativamente (P 0,05). Por outro lado, nos grupos tratados com An-AgNps + MTX, foram revertidos os níveis de todos os biomarcadores semelhantes ao NC. Em conclusão, os resultados mostram que o An-AgNps tem um efeito protetor contra a hepatotoxicidade induzida pelo MTX e o estresse oxidativo.

5.
São Paulo med. j ; 142(4): e2023113, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1536910

RESUMEN

ABSTRACT BACKGROUND: To the best of our knowledge, this is the first study to evaluate the effectiveness of specific concentrations of antibiofilm agents, such as N-acetyl cysteine (NAC), rifampicin, and ozone, for the treatment of pan-resistant Klebsiella pneumoniae (PRKp). OBJECTIVES: We evaluated the effectiveness of antibiofilm agents, such as NAC, rifampicin, and ozone, on biofilm formation in PRKp at 2, 6, 24, and 72 h. DESIGN AND SETTING: This single-center experimental study was conducted on June 15, 2017, and July 15, 2018, at Istanbul Faculty of Medicine, Istanbul University, Turkey. METHODS: Biofilm formation and the efficacy of these agents on the biofilm layer were demonstrated using colony counting and laser-screened confocal microscopy. RESULTS: NAC at a final concentration of 2 μg/mL was administered to bacteria that formed biofilms (24 h), and no significant decrease was detected in the bacterial counts of all isolates (all P > 0.05). Rifampicin with a final concentration of 0.1 μg/mL was administered to bacteria that formed biofilm (24 h), and no significant decrease was detected in bacterial count (all P > 0.05). Notably, ozonated water of even 4.78 mg/L concentration for 72 h decreased the bacterial count by ≥ 2 log10. CONCLUSION: Different approaches are needed for treating PRKp isolates. We demonstrate that PRKp isolates can be successfully treated with higher concentrations of ozone.

6.
Braz. j. oral sci ; 23: e241938, 2024. ilus
Artículo en Inglés | LILACS, BBO | ID: biblio-1532506

RESUMEN

Aim: To evaluate changes in the surface roughness and morphology of a nanofilled composite following toothbrushing with a whitening (WT) or regular toothpaste (RT), alone or combined with 35% hydrogen peroxide bleaching (HP). Methods: Seventy disc-shaped nanofilled composite (Filtek Z350XT) specimens were randomly divided into groups (n=10): WT, RT, TB (without toothpaste ­ control) or the combinations WT/ HP, RT/HP, TB/HP and HP. All groups underwent toothbrushing simulation (60,000 cycles) and bleaching treatment (4 sessions). Mean surface roughness (Ra, µm) was measured before (T0) and after treatments (TB). Surface morphology was assessed by scanning electron microscopy (SEM) at TB. Mean Ra was analyzed using general mixed models and multiple comparisons by the Tukey-Kramer test (α=5%). Results: HP caused no surface roughness changes on the nanofilled composite after treatment (p>0.05). RT toothbrushing, combined or not with HP, increased the surface roughness (p<0.05). WT and WT/ HP protocols had no effect on the surface roughness of the composite (p>0.05). The nanofilled composite submitted to RT toothbrushing combined with HP (RT/HP) presented substantial surface alterations under SEM, showing deep depressions and round-shaped defects. Toothbrushing with RT combined with the bleaching agent increased exposure of the inorganic fillers. Conclusion: WT toothbrushing, regardless of HP combination, or the single HP protocol had no effect on the surface roughness of the nanofilled composite. However, RT combined with HP negatively affected surface roughness and presented the most noticeable surface changes among groups


Asunto(s)
Blanqueamiento de Dientes , Pastas de Dientes , Microscopía Electrónica de Rastreo , Resinas Compuestas , Peróxido de Hidrógeno
7.
Braz. dent. sci ; 27(1): 1-7, 2024. ilus, tab
Artículo en Inglés | LILACS, BBO | ID: biblio-1532450

RESUMEN

Objective: The aim of this study was to determine if SEM used with imaging software could be used to quantitatively determine the extent of dentine roughness due to tooth-brushing. Material and methods: Flat, polished dentine surfaces were subjected to 25,000 cycles of simulated tooth-brushing at 2 strokes per second with a load of 200 g. At the end of the brushing cycle, dentine surfaces were first assessed using profilometry and then subjected to SEM analysis. Ra (average roughness) readings were obtained for profilometric assessment. Using imaging software, the horizontal distance between adjacent characteristic grooves noted on micrographs was measured, ensuring that the middle of each crest of the associated groove was used as the reference point, the Crest-to-Crest distance (C-C distance). These two parameters were examined statistically for correlation. Results: When Spearman Rank tests were utilized the correlation between average Ra and crest to crest measurements was 0.709 (p <0.01). The Bland Altman plot, however, showed poor agreement between the two test parameters. Conclusion: Further work is needed to validate the use of this methodology in the quantitative assessment of tooth surface loss due to abrasion (AU)


Objetivo: O objetivo deste estudo foi determinar se o MEV usado com software de imagem poderia ser usado para determinar quantitativamente a extensão da rugosidade da dentina devido à escovação dentária. Material e Métodos: Superfícies dentinárias planas e polidas foram submetidas a 25.000 ciclos de escovação dentária simulada a 2 movimentos por segundo com uma carga de 200g. No final do ciclo de escovação, as superfícies dentinárias foram primeiro avaliadas por perfilometria e depois submetidas à análise MEV. Leituras de Ra (rugosidade média) foram obtidas para avaliação perfilométrica. Utilizando um software de imagem, foi medida a distância horizontal entre sulcos característicos adjacentes observados nas micrografias, garantindo que o meio de cada crista do sulco associado fosse usado como ponto de referência, a distância crista a crista (distância CC). Esses dois parâmetros foram examinados estatisticamente para correlação. Resultados: Quando foram utilizados os testes de Spearman Rank, a correlação entre a média de Ra e as medidas de crista a crista foi de 0,709 (p<0,01). O gráfico de Bland Altman, no entanto, mostrou fraca concordância entre os dois parâmetros de teste. Conclusão: Mais trabalhos são necessários para validar o uso desta metodologia na avaliação quantitativa da perda da superfície dentária devido à abrasão(AU)


Asunto(s)
Propiedades de Superficie , Abrasión de los Dientes , Cepillado Dental , Microscopía Electrónica de Rastreo , Dentina
8.
Rev. nav. odontol ; 50(2): 5-14, 20232010.
Artículo en Portugués, Inglés | LILACS-Express | LILACS | ID: biblio-1518550

RESUMEN

Considerando o uso de brocas para remoção da resina residual após descolagem do braquete e a possibilidade de injúrias à superfície do esmalte após o uso dessas brocas, este trabalho teve como objetivo realizar um estudo experimental, para avaliar a variação do aspecto superficial do esmalte de forma qualitativa, por meio da avaliação com imagens topográficas do esmalte dentário, utilizando-se a Microscopia Eletrônica de Varredura (MEV), a qual permitiu ilustrar e avaliar a superfície do esmalte após a fase de polimento final, realizada por dois métodos: taça de borracha ou escova Robinson. Foram utilizados 25 dentes pré-molares humanos, obtidos a partir de exodontias em pacientes que procuraram voluntariamente o curso de Residência em Cirurgia da Clínica Odontológica Universitária da Universidade Estadual de Londrina. Os dentes foram divididos em quatro grupos: A, B, C e D, contendo 6 dentes cada, de acordo com as brocas utilizadas para a remoção do remanescente adesivo e o polimento escolhido, além de um dente como "controle". Foi avaliada a rugosidade superficial do esmalte após a remoção da resina e a superfície do esmalte após o polimento com as duas opções apresentadas. Os resultados mostraram que, por observação e inspeção, as brocas removeram a resina residual de todos os dentes, porém, causaram riscos e ranhuras, como evidenciado nas imagens em MEV. Concluiu-se que não houve diferença estatística entre os métodos de polimento e que ambos foram importantes para a redução das marcas abrasivas, proporcionando uma superfície mais lisa do esmalte.


Considering the use of specific burs to remove residual resin after bracket debonding and the possibility of injuries to the dental enamel after using these burs, this study aimed to verify the variation in the enamel surface appearance in a qualitative way and evaluation with topographic images of the dental enamel. The use of Scanning Electron Microscopy (SEM) allowed to illustrate and evaluate the enamel surface after the final polishing phase using two methods: rubber cup or Robinson brush. Twenty-five human premolar teeth were obtained from extractions in patients who voluntarily sought the Oral Maxillofacial Surgery Residency at the Dental School from the State University of Londrina; the teeth were divided into four groups A, B, C and D containing 6 teeth each according to the burs used to remove the remaining adhesive and the chosen polishing, in addition to one tooth as a "control". Dental enamel surface roughness was evaluated after resin removal and enamel surface after polishing with the two methods presented. The results showed that by observation and inspection, the burs removed residual resin from all teeth, however, caused scratches and grooves as evidenced in the SEM images. Based on the results, there was no statistical difference between the polishing methods, and both were important for the reduction of abrasive marks and provided a smoother enamel surface.

9.
Indian J Ophthalmol ; 2023 Sep; 71(9): 3270
Artículo | IMSEAR | ID: sea-225253

RESUMEN

Background: Ophthalmic dirofilariasis is an uncommon zoonotic parasitic infection caused by species of Dirofilaria, a dog tapeworm that is transmitted to human by mosquitoes. Man is a dead?end host for the parasite. Ophthalmic involvement is rare and includes periorbital, subconjunctival, subtenon, and intra?ocular involvement. We report the removal of a subconjunctival worm and identification by light microscopy (LM) and scanning electron microscopy (SEM). Purpose: A 62?year?old female presented with complaints of redness, discharge, and foreign body sensation with difficulty in opening eyes in the left eye for the last 3 days. The patient is a non?vegetarian. On examination, her best corrected visual acuity in both eyes was 20/20. On slit lamp examination, there was a long, thin, round, coiled white subconjunctival live worm in the left eye superiorly. The rest of anterior segment evaluation, intra?ocular pressure, and fundus was normal in both eyes. The parasite was removed under local anesthesia from subconjunctival space [Video]. External surface morphology under LM revealed fine transverse cuticular striations with tapered cephalic and caudal ends. Uterus was long and coiled with indistinguishable masses inside. The finding was also confirmed by SEM. Synopsis: A subconjuctival parasite was removed and identified as Dirofilaria repens by characteristic LM and SEM findings. Highlight: Dirofilaria species may lodge in many tissues of human bodies including eye and adnexa. Dirofilaria is a natural parasite of carnivorous animals, mostly dogs, cats, and foxes.[1] The most common mode of transmission to human is usually by bite of mosquitoes like Culex and Aedes, which are considered as vectors, and it is often thought that parasitemia is because of accidental conduction.[1] Simple surgical removal of the worm is curative. After removal, the worm should be visualized directly under LM. All the internal structures of the transparent worm could be seen and compared with those under SEM.

10.
Int. j. morphol ; 41(4): 1219-1227, ago. 2023. ilus
Artículo en Inglés | LILACS | ID: biblio-1514335

RESUMEN

SUMMARY: In this study we describe the functional morphology of Cornu aspersum (Helix aspersa), spermatozoa using light, scanning (SEM) and transmission electron (TEM) microscopies. The studies were performed with sperm located in the frozen hermaphroditic duct. Our results showed that the head presents an elongated conical shape slightly coiled in a corkscrew, with the nucleus partially covered by an acrosome, where an apical vesicle is located at the lateralized apex. This peculiar shape suggests the helical displacement movement of the spermatozoa. The head and the nucleus are slightly larger size compared to those of other gastropod species. The intermediate tract is surrounded by a mitochondrial complex and a glycogen helix. The glycogen helix is coiled helically along the intermediate tract, presenting at least five twists of glycogen helices. The complexity of both the mitochondrial complex and the glycogen helix suggests a high metabolic consumption considering the long period of time until fertilization occurs. Our findings on the detailed characterization of Cornu aspersum spermatozoa, obtained from a frozen hermaphroditic duct can contribute to a better understanding of the functional morphology of sperm and serve as a reference for future studies.


En este estudio describimos la morfología funcional de Cornu aspersum (Helix aspersa), espermatozoides utilizando microscopías de luz, barrido (SEM) y electrónica de transmisión (TEM). Los estudios se realizaron con espermatozoides localizados en el conducto hermafrodita congelado. Nuestros resultados mostraron que la cabeza presenta una forma cónica alargada ligeramente enrollada en un tirabuzón, con el núcleo parcialmente cubierto por un acrosoma, donde se ubica una vesícula apical en el ápice lateralizado. Esta peculiar forma sugiere el movimiento de desplazamiento helicoidal de los espermatozoides. La cabeza y el núcleo son de un tamaño ligeramente mayor en comparación con los de otras especies de gasterópodos. El tracto intermedio está rodeado por un complejo mitocondrial y una hélice de glucógeno. La hélice de glucógeno se enrolla helicoidalmente a lo largo del tracto intermedio, presentando al menos cinco giros de hélices de glucógeno. La complejidad tanto del complejo mitocondrial como de la hélice de glucógeno sugiere un alto consumo metabólico considerando el largo período de tiempo hasta que ocurre la fecundación. Nuestros hallazgos sobre la caracterización detallada de los espermatozoides de Cornu aspersum, obtenidos de un conducto hermafrodita congelado, pueden contribuir a una mejor comprensión de la morfología funcional de los espermatozoides y servir como referencia para futuros estudios.


Asunto(s)
Animales , Caracoles , Espermatozoides/ultraestructura , Espermatozoides/fisiología , Microscopía Electrónica de Rastreo , Criopreservación , Microscopía Electrónica de Transmisión , Organismos Hermafroditas
11.
Odovtos (En línea) ; 25(2)ago. 2023.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1448738

RESUMEN

The aim of this study was to evaluate the whitening and abrasion effects of dentifrices containing different whitening agents on artificially stained and unstained enamel. 160 human dental enamel discs were distributed into four groups according to the type of dentifrices applied on them (n=40): Group I, non-whitening dentifrice (control group); Group II, dentifrice containing charcoal; Group III, dentifrice containing blue covarine; Group IV, dentifrice containing hydrogen peroxide. Half of the specimens in each group were immersed in coffee solution. Color measurements were evaluated from stained and unstained specimens before and after brushing by a spectrophotometer. The surface roughness of each unstained specimen was analyzed using a profilometer after the brushing and bleaching. The surface of one randomly selected specimen from each group was observed using a scanning electron microscope (SEM). Statistical analysis of the color change was performed using the Kruskal-Wallis test. The one-way ANOVA was used to evaluate surface roughness. Group III provided significantly higher recovery on ΔE00 values than other groups on the unstained enamel (p<0.05). Group IV showed significantly the highest ΔE00 values on stained enamel (p<0.05) and also Group IV showed the highest surface roughness values (p<0.05), SEM revealed a more irregular surface in groups III and IV. It can be stated that dentifrice containing blue covarine is both an effective and a safe way to provide whiter teeth with routine home tooth brushing.


El objetivo de este estudio fue evaluar los efectos de blanqueamiento y abrasión de los dentífricos que contienen diferentes agentes blanqueadores en el esmalte teñido y no teñido artificialmente. Se distribuyeron 160 discos de esmalte dental humano en cuatro grupos según el tipo de dentífrico aplicado sobre ellos (n=40): Grupo I, dentífrico no blanqueador (grupo control); Grupo II, dentífrico que contiene carbón vegetal; Grupo III, dentífrico que contiene azul; Grupo IV, dentífrico que contiene peróxido de hidrógeno. La mitad de los especímenes de cada grupo se sumergieron en una solución de café. Las mediciones de color se evaluaron a partir de especímenes teñidos y no teñidos antes y después del cepillado con un espectrofotómetro. La rugosidad de la superficie de cada muestra sin teñir se analizó utilizando un perfilómetro después del cepillado y del clareamiento. La superficie de un espécimen seleccionado al azar de cada grupo se observó utilizando un microscopio electrónico de barrido (MEB). El análisis estadístico del cambio de color se realizó utilizando la prueba de Kruskal-Wallis. Se utilizó el ANOVA para evaluar la rugosidad de la superficie. El grupo III proporcionó una recuperación significativamente mayor en los valores de ΔE00 que otros grupos en el esmalte no teñido (p<0,05). El Grupo IV mostró significativamente los valores más altos de ΔE00 en el esmalte teñido (p<0.05) y también el Grupo IV mostró los valores más altos de rugosidad superficial (p<0.05), el análisis en MEB reveló una superficie más irregular en los grupos III y IV. Se puede afirmar que el dentífrico que contiene azul es una forma efectiva y segura de proporcionar dientes más claros con el cepillado de rutina en el hogar.

12.
Odovtos (En línea) ; 25(2)ago. 2023.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1448740

RESUMEN

The first objective of this research was to evaluate the effectiveness of XP-Endo Finisher on dentinal tubule penetration of irrigation solution using confocal laser scanning microscopy. The main purpose of this research was to compare the effect of cold lateral condensation, continuous wave obturation and core-carrier based techniques on sealer penetration. Sixty mandibular premolars were prepared and allocated into two experimental groups (n=30) as the final irrigation technique and obturation technique experiment. In the final irrigation technique experiment, final irrigation was performed with XP-Endo Finisher, passive ultrasonic irrigation (PUI) and conventional needle irrigation (CNI) (n=10). The roots in the obturation technique experiment were also assigned into 3 groups and obturated with cold lateral condensation, continuous-wave obturation and core-carrier techniques (n=10). The most effective activation method, which emerged as a result of the first part of this study, was used as the final irrigation method in the obturation technique experiment. Then, all roots were sectioned in 1-mm-thick slices at 3mm from the apex for scanning. In terms of depth and percentage of material penetration, CNI exhibited significantly the lowest values and no significant difference was found between others. Also, there was no significant difference among obturation methods. In conclusion, XP-Endo Finisher and PUI are more effective than CNI on irrigant penetration. Sealer penetration into dentinal tubules is independent of obturation techniques.


El objetivo principal de esta investigación fue evaluar la eficacia de XP- Endo Finisher en la penetración de la solución de irrigación en los túbulos dentinarios mediante microscopía de láser confocal. Se prepararon sesenta premolares mandibulares y se distribuyeron en dos grupos experimentales (n=30) según el tipo de método de evaluación utilizado. En el experimento de la técnica de irrigación final, la irrigación final se realizó con XP-Endo Finisher, irrigación ultrasónica pasiva (PUI) e irrigación con aguja convencional (CNI) (n=10). Las raíces en el experimento de la técnica de obturación también se asignaron en 3 grupos y se obturaron con técnicas de condensación lateral fría, obturación de onda continua y portador de núcleo (n=10). El método de activación más eficaz, que surgió como resultado de la primera parte de este estudio, se utilizó como método de irrigación final en el experimento de la técnica de obturación. Luego, todas las raíces se seccionaron en muestras de 1mm de espesor. En términos de profundidad y porcentaje de penetración del material, CNI exhibió significativamente los valores más bajos y no se encontraron diferencias significativas entre los demás. Además, no hubo diferencias significativas entre los métodos de obturación. En conclusión, XP-Endo Finisher y PUI son más efectivos que CNI en la penetración del irrigante. La penetración del sellador en los túbulos dentinarios es independiente de las técnicas de obturación.

13.
Odovtos (En linea) ; 25(1)abr. 2023.
Artículo en Inglés | LILACS, SaludCR | ID: biblio-1422197

RESUMEN

This study evaluated selected structural and physical properties, such as degree of conversion (DC), Vickers hardness (VHN), and compression strength (CS), of three new dual-cure bulk-fill resin-based composites (RBCs; ACTIVA, HyperFIL, and Fill-Up) and compared them to those of a conventional RBC (Filtek Z250) at three clinically relevant depths. Samples (n=180) were prepared in three depths (2,4, and 6mm). Fourier-transform infrared spectroscopy (FTIR) analysis and VHN and CS tests were performed. The DC value was calculated by considering the relative change in the aliphatic C=C peaks. The fractured surfaces of representative samples were characterized using scanning electron microscopy (SEM). Data were statistically evaluated using two-way analysis of variance and post hoc Bonferroni tests (p<0.05). According to the VHN results, Filtek Z250 showed the highest bottom/top hardness ratio (97.94±1.01) at 2mm thickness and ACTIVA showed the lowest bottom/top hardness ratio (43.48±5.64) at 6mm thickness (p<0.001). According to the FTIR results, the DC decreased with increasing thickness in all materials (p<0.05). Filtek Z250 showed the highest (301±12.4 MPa) and ACTIVA exhibited the lowest (232±17.2 MPa) CS values at 2mm thickness (p<0.05). The lowest CS values were obtained for ACTIVA, and the highest values were obtained for Filtek Z250 for samples with thicknesses of 4 and 6mm, respectively (p<0.05). The structural features of restorative composites, such as the resin chemistry and filler type and content, and the operational parameters (i.e., material thickness and curing conditions) strongly affect crosslinking reactions and thus the DC, VHN, and CS values.


Este estudio evaluó propiedades físicas y estructurales, como el grado de conversión (DC), la dureza Vickers (VHN) y la resistencia a la compresión (CS), de tres nuevos compósitos a base de resina de curado dual tipo bulk (RBC; ACTIVA , HyperFIL y Fill-Up) y los comparó con los de una resina compuesta convencional (Filtek Z250) en tres profundidades clínicamente relevantes. Se prepararon muestras (n=180) en tres profundidades (2,4 y 6mm). Se realizaron análisis de espectroscopia infrarroja por transformada de Fourier (FTIR) y pruebas VHN y CS. El valor de DC se calculó considerando el cambio relativo en los picos alifáticos C=C. Las superficies fracturadas de muestras representativas se caracterizaron mediante microscopía electrónica de barrido (MEB). Los datos se evaluaron estadísticamente mediante análisis de varianza de dos vías y pruebas post hoc de Bonferroni (p<0,05). De acuerdo con los resultados de VHN, Filtek Z250 mostró la relación de dureza inferior/superior más alta (97,94±1,01) con un espesor de 2mm y ACTIVA mostró la relación de dureza inferior/superior más baja (43,48±5,64) con un espesor de 6mm (p<0,001). De acuerdo con los resultados de FTIR, la DC disminuyó al aumentar el espesor en todos los materiales (p<0,05). Filtek Z250 mostró los valores de CS más altos (301±12,4 MPa) y ACTIVA los más bajos (232±17,2 MPa) a 2mm de espesor (p<0,05). Los valores más bajos de CS se obtuvieron para ACTIVA y los valores más altos para Filtek Z250 para muestras con espesores de 4 y 6mm, respectivamente (p<0,05). Las características estructurales de las resinas compuestas de restauración, como la química; además del tipo y contenido del relleno, y los parámetros operativos (es decir, el espesor del material y las condiciones de curado) afectan en gran medida las reacciones de interacción química y, por lo tanto, los valores de DC, VHN y CS.


Asunto(s)
Microscopía Electrónica de Rastreo , Resinas Compuestas/análisis , Fuerza Compresiva
14.
Artículo | IMSEAR | ID: sea-222451

RESUMEN

Background: The laser therapy has been used as an adjuvant for conventional periodontal disease as they exhibit a bactericidal effect on scaling and root planning by its thermal and photo disruptive effects on the pathogens. This study focuses on the structural and compositional changes induced on the root surfaces of teeth following diode laser (DL) application with increasing quantum of exposure time. Objective: The objective of this study was to evaluate the structural and compositional changes on the root surface of extracted human permanent teeth after application of DLs (810 nm) with varying time interval. Materials and Methods: Twenty samples of single?rooted periodontally compromised extracted teeth were utilized for this study. Root planning was done and the roughness caused by the instrumentation was measured using profilometric analysis. Then, the samples were divided into four groups, with DL application time: Group 1 – laser application for 15 s, Group 2 – laser application for 30 s, Group 3 – laser application for 45 s, and Group 4 – laser application for 60 s. A scanning electron microscope was used to examine the cemental surface and energy?dispersive X?ray analysis software assesses the compositional changes of the teeth in each group. Results: This study reveals that on exposure of DL (810 nm) on the root surface when time of exposure increases, there were relative increases in surface irregularities and charring. There were significant changes in the chemical composition of the tooth surface.

15.
Braz. dent. j ; 34(1): 45-51, Jan.-Feb. 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS, BBO | ID: biblio-1420579

RESUMEN

Abstract Considering the side effects in the oral cavity and dental structures of radiotherapy (RDT) for head and neck cancer, this study aimed to evaluate the effects of RDT on the root dentin concerning the obliteration of dentinal tubules, the inorganic composition of intra-radicular dentin, and the integrity of collagen fibers. Thirty human canines were selected from a biobank and randomly divided into two groups (n=15). The samples were sectioned buccolingually, and a hemisection was used for structural analysis by scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometer (EDS). Low-vacuum SEM images were obtained at 2000-x magnification to observe the obliteration of the dentinal tubules. Moreover, compositional evaluation was performed using EDS. After RDT, the SEM and EDS analyses were repeated using the same methodology. RDT was applied fractionally at 2 Gy per day, 5 days per week, for 7 weeks, resulting in a total dose of 70 Gy. The collagen integrity of the irradiated and non-irradiated samples was analyzed using Masson's trichrome and picrosirius red staining polarization microscopy. Samples subjected to RDT exhibited dentinal tubule obliteration (p < 0.001); low integrity of type I and III collagen fibers (p < 0.05); compositional reduction of calcium (p = 0.012), phosphorus (p = 0.001), and magnesium (p < 0.001); an increased Ca/P ratio (p < 0.001). RDT affects the structure of dentinal tubules, the inorganic composition of intra-radicular dentin, and the collagen fiber integrity in the root dentin, which may interfere with the effectiveness and durability of dental procedures.


Resumo Considerando os efeitos colaterais na cavidade oral e estruturas dentárias da radioterapia (RDT) para o câncer de cabeça e pescoço, este estudo teve como objetivo avaliar os efeitos da RDT sobre a dentina radicular quanto à obliteração dos túbulos dentinários, a composição inorgânica da dentina intra-radicular e a integridade das fibras colágenas. Trinta caninos humanos foram selecionados de um biobanco e divididos aleatoriamente em dois grupos (n=15). As amostras foram seccionadas no sentido vestíbulo-lingual, e uma hemissecção foi utilizada para análise estrutural por microscopia eletrônica de varredura (MEV) e espectrômetro de raios X de dispersão de energia (EDS). Imagens de MEV de baixo vácuo foram obtidas com aumento de 2500x para observar a obliteração dos túbulos dentinários. Além disso, a avaliação composicional foi realizada usando EDS. Após a RDT, as análises em MEV e EDS foram repetidas usando a mesma metodologia. A RDT foi aplicada fracionada a 2 Gy por dia, 5 dias por semana, durante 7 semanas, resultando em uma dose total de 70 Gy. A integridade do colágeno das amostras irradiadas e não irradiadas foi analisada usando microscopia de polarização de coloração com tricrômio de Masson e picrosirius red. As amostras submetidas a RDT apresentaram obliteração dos túbulos dentinários (p < 0,001); baixa integridade das fibras colágenas tipo I e III (p < 0,05); redução composicional de cálcio (p = 0,012), fósforo (p = 0,001) e magnésio (p < 0,001); e uma relação Ca/P aumentada (p < 0,001). A RDT afeta a estrutura dos túbulos dentinários, a composição inorgânica da dentina intra-radicular e a integridade das fibras colágenas na dentina radicular, o que pode interferir na eficácia e durabilidade dos procedimentos odontológicos.

16.
China Tropical Medicine ; (12): 930-2023.
Artículo en Chino | WPRIM | ID: wpr-1016373

RESUMEN

@#Abstract: Objective To understand the morphological characteristics and ultrastructure of the dominant species of Rhipicephalus sanguineus in Hainan at different developmental stages, and provide theoretical basis for the identification of the lineage and control of Rhipicephalus sanguineus. Methods The external morphology of different developmental stages of the dominant species of Rhipicephalus sanguineus, including larva, nymph and adult tick in Hainan were observed by scanning electron microscope. Results The division between each segment of larva pedipalps was not obvious, and setae was serrated; dental formula type 2 | 2; 3 pairs of podomere; a pair of setae on the anal valve; none of anal groove, spiracular plate, porous area and genital aperture. There was a clear boundary at the beginning of each segment of nymph pedipalps; dental formula type 2 | 2; 4 pairs of podomere; 3 pairs of setae on the anal valve; anal groove; none of porous area and genital aperture. The male adult tick's trichotheca are covered by the pedipalps, and the whole bristles are conical; dental formula type 3 | 3; 4 pairs of podomere; anal groove and paraprocts; 7 setae on the anal valve; genital aperture was oval. The female of adult tick can be distinguished by dental formula 3 | 3; pairs of podomere; porous areas with 3 short setae; anal groove; 4 pairs of setae and 2 pores on the anal valve; genital pore was broadly U-shaped. In addition, the male adult's scutum occupies almost the entire dorsal surface, the basis capituli of larva, nymph and adult tick all were hexagonal, and the existence of Haller's organ was found on the first pair of legs. Conclusions Scanning electron microscopy observation of the different developmental stages of R.sanguineus revealed clear morphological features, preliminarily suggesting that R.sanguineus in Hainan Province may belong to the tropical lineage, which provide a certain experimental basis for the identification of the tick and the comprehensive prevention and control of local tick-borne diseases.

17.
Chinese Pharmacological Bulletin ; (12): 310-314, 2023.
Artículo en Chino | WPRIM | ID: wpr-1013858

RESUMEN

Aim To explore the mechanism of the natural phenolic compound pterostilbene(PTE)in the protection of liver ischemic/reperfusion. Methods A total of 40 C57 mice were divided into control group,model group,drug delivery group and treatment group and a 70% liver ischemic/reperfusion(ischemic 60 min)model was established,then primary LSECs were isolated by perfusion and digestion. Hepatic structural disruption was observed by HE staining. The ultrastructure of hepatic sinus endothelial cells was observed by transmission electron microscopy(TEM). The structure of LSECs fenestrae was observed by scanning electron microscopy(SEM). The expression level of heme oxygenase 1(HO-1)in LSECs was detected by Western blot. Results HE staining showed that PTE protected against hepatic ischemic injury. TEM observed that PTE had a protective effect on hepatic sinus endothelial cells,and the number of LSECs fenestrae in the blank control group was larger and the number of fenestrae in the liver I/R model group was reduced. The number of LSECs fenestrae in the liver I/R model group treated with PTE increased compared with the untreated liver I/R model group. Western blot result showed that PTE was able to induce HO-1 expression in LSECs. Conclusions PTE alleviates oxidative damage of endothelial cells in mouse hepatic sinus by inducing HO-1expression,and protects the liver from ischemia/reperfusion injury.

18.
Journal of Preventive Medicine ; (12): 989-991, 1012, 2023.
Artículo en Chino | WPRIM | ID: wpr-1013272

RESUMEN

Objective @#To investigate the spatiotemporal clustering characteristics of hand, foot, and mouth disease in Shangcheng District, Hangzhou City in 2021, so as to provide insights into prevention and control of hand, foot, and mouth disease. @*Methods@#Data pertaining to the incidence of hand, foot and mouth disease in Shangcheng District in 2021 were collected from Chinese Disease Prevention and Control Information System, spatial and temporal distribution of hand, foot and mouth disease were described, and the spatiotemporal clusters were identified.@*Results@#A total of 2 473 cases with hand, foot and mouth disease were reported in Shangcheng District in 2021, with a reported incidence rate of 186.86/105. The incidence of hand, foot and mouth disease appeared a bimodal distribution, with the first peak seen during the period between May and July (1 164 cases, 47.07%) and the second peak during the period between October and December (659 cases, 26.65%). Hand, foot and mouth disease was reported across all streets in Shangcheng District, with the highest incidence seen in Dinglan Street (398.84/105). There were one primary cluster and ten secondary clusters of hand, foot and mouth disease, and the primary cluster was centered in Jianqiao Street with 1.81 km in radius, which covered 9 communities in Jianqiao Street and was clustered during the period from March 19 and April 13. Of the 10 secondary clusters, there were three clusters in Dinglan Street, one in each of Jiubao, Sijiqing, Wangjiang and Kaixuan streets, and three clusters crossing streets. In addition, no spatiotemporal clusters of hand, foot and mouth disease were identified in Nanxing Street, Qingbo Street or Ziyang Street.@*Conclusion@#There was a remarkable spatiotemporal cluster in the incidence of hand, foot and mouth disease in Shangcheng District in 2021, with the peaks in incidence from May to July and from October to December, and the incidence of hand, foot and mouth disease was mainly clustered in the urban-rural junction and the central urban regions.

19.
Tropical Biomedicine ; : 392-399, 2023.
Artículo en Inglés | WPRIM | ID: wpr-1011282

RESUMEN

@#Blastocystis is a prevalent infectious agent found in the gastrointestinal tract of humans and animals. While the morphology of Blastocystis has been extensively studied, there is still a lack of comprehensive research on its ultrastructure, especially regarding surface characteristics and their correlation with pathogenic potential. Additionally, the subtyping of Blastocystis does not provide information on the isolate’s pathogenicity. This study aimed to examine the morphology and the cell surface of Blastocystis in avian and non-human primates, including peafowl, pheasant, and lion-headed tamarin. By employing light microscopy and scanning electron microscopy (SEM), this study provides the first evidence of the cellular and surface features of Blastocystis in these animal species. Our findings revealed distinct variations in cell size, shape, and surface morphology among the different host species. Notably, the isolates from peafowl exhibited larger cell sizes compared to the isolates from the pheasant. However, interestingly, both animal species were found to exhibit the same Blastocystis ST6. It was also observed that the surface structure of Blastocystis from different hosts displayed a diverse range of patterns, including mesh-like appearances, deep indentations, and attachments to bacteria. Additionally, findings also revealed the presence of a rough surface structure in peafowl, a characteristic that has been previously linked to pathogenicity and symptomatic infection in animals, as indicated by earlier studies. The findings contribute to our understanding of the morphological features and the surface characteristic of Blastocystis in different host species, shedding light on the parasite’s adaptations and potential implications for host health.

20.
Chinese Journal of Biotechnology ; (12): 3710-3723, 2023.
Artículo en Chino | WPRIM | ID: wpr-1007987

RESUMEN

As central players in cellular structure and function, proteins have long been central themes in life science research. Analyzing the impact of protein sequence variation on its structure and function is one of the important means to study proteins. In recent years, a technology called deep mutational scanning (DMS) has been widely used in the field of protein research. It introduces thousands of mutations in parallel in specific regions of proteins through high-abundance DNA libraries. After screening, high-throughput sequencing is employed to score each mutation, revealing sequence-function correlations. Due to its high-throughput, fast and easy, and labor-saving features, DMS has become an important method for protein function research and protein engineering. This review briefly summarizes the principle of DMS technology, highlighting its applications in mammalian cells. Moreover, this review analyzes the current technical bottlenecks, aiming to facilitate relevant research.


Asunto(s)
Animales , Mutación , Proteínas/química , Ingeniería de Proteínas , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Mamíferos/genética
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