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Objective: To investigate the color alterations in enamel following the use of different orthodontic bonding resins and adhesive residue–removal burs.Materials and Methods:Metal brackets were bonded to extracted human premolars (n = 175) by using an etch-and-rinse adhesive system, a self-etch adhesive system (SEP), or a resin-modified glass ionomer cement (RMGIC). After 24 hours of photoaging, the brackets were removed and the adhesive residue on the tooth surfaces was cleaned with either a tungsten carbide bur or a Stainbuster bur. Tooth colors were measured with a spectrophotometer at baseline, after adhesive removal, and after additional photoaging. Color evaluation was made, and color differences induced by photoaging were calculated. Statistical evaluation was made using the Kruskal-Wallis test and the Mann-Whitney U-test, with Bonferroni correction.Results:All specimens showed discoloration at varying levels. The highest color change was observed in the etch-and-rinse adhesive/tungsten carbide bur group. When the etch-and-rinse and self-etch adhesives were used, adhesive-remnant removal with Stainbuster burs resulted in significantly lower discoloration. The type of bur did not affect the extent of enamel discoloration in the RMGIC group.Conclusions:Orthodontic treatment alters the original color of enamel, and both the adhesive system and the resin-removal methods are responsible for this change. When brackets are bonded with the etch-and-rinse system or the SEP, cleaning the adhesive residuals with Stainbuster burs is recommended for minimal change. RMGIC can be safely cleaned with tungsten carbide burs. 相似文献
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Hacer Ilbilge Ertoy Karagol Dilek Yapar Odul Egritas Gurkan Sinan Sari Mustafa Necmi Ilhan Buket Dalgic Arzu Bakirtas 《The Turkish journal of gastroenterology》2021,32(4):365
BackgroundThere has been no valid and reliable Turkish scale that measures symptoms in children with eosinophilic esophagitis (EoE). The aim of the study is to test the validity and reliability of the Turkish version of Pediatric Eosinophilic Esophagitis Symptom Scores® (Tr-PEESS v2.0).Methods Relevant forms of Tr-PEESS v2.0 were applied to 2-18 years old children with EoE and to their parents. KINDL QoL patient and parent questionnaires and the GaziESAS scale developed in this study were used to test the convergent validity of Tr-PEESS v2.0. Discriminant validity was evaluated among 3 EoE treatment groups: under treatment, off treatment due to remission, and uncompliant with treatment. Reliability was evaluated by internal consistency, test–retest reliability, and item analysis.Results Fifty-two children/teens (mean age 130.2 ± 60.3 months) and 84 parents were interviewed twice one week apart. The mean duration of EoE was 47.2 ± 35.6 months. Tr-PEESS v2.0 reports correlated with GaziESAS (range 0.361-0.855) and KINDL QoL questionnaires (range −0.316 to 0.413). Parent report of Tr-PEESS v2.0 discriminated children uncompliant with treatment from the ones off treatment and undertreatment. Cronbach’s α values and intraclass correlation coefficients (ICC) values of Tr-PEESS v2.0 ranged from 0.614-0. 895 and 0.646-0.910, respectively.Conclusion Tr-PEESS v2.0 is a valid and reliable tool to use in Turkish children. GaziESAS is a new parent-proxy pediatric EoE scale with an additional adaptive behavior domain that passed scale developmental stages successfully for Turkish children with EoE. 相似文献
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Anggraini Permata Sari Nikko Darnindro Aryan Yohanes Muhammad Ikhsan Mokoagow 《Medicine》2021,100(12)
Rationale:Bacterial and fungal infections in Coronavirus Disease-19 (COVID-19) patients have been inadequately investigated and reported thus far. The safety profile of tocilizumab (TCZ) administration in candidemia patient still debatable.Patient concerns:A 54 year-old woman presenting with weakness on the left side of her body was diagnosed with COVID-19. After 7 days of admission, her condition worsened and developed respiratory distress and was having respiratory distress despite standard treatment.Diagnoses:Acute respiratory distress syndrome (ARDS) in COVID 19 was diagnoses based on real time-PCR swab, deterioration of PaO2/FiO2 and increased of acute phase reactants.Interventions:Anti Interleukin–6 (IL-6) was considered to tackle her inflammatory condition. Prior to TCZ administration, blood culture was performed and the result came with Candida tropicalis in the absence of bacterial growth.Outcomes:No major complications associated with intravenous antifungal or TCZ occurred. After 40 days of hospitalization, the patient''s clinical condition improved and was finally discharged.Lessons:This case underscores the safety profile of giving TCZ in candidemia as a secondary infection in severe COVID-19 patient. 相似文献
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Sachin Kochrekar Ajit Kalekar Shweta Mehta Pia Damlin Mikko Salomki Sari Granroth Niko Meltola Kavita Joshi Carita Kvarnstrm 《RSC advances》2021,11(32):19844
This study reports the electropolymerization of novel keto functionalized octaethyl metal porphyrins (Zn2+ and Ni2+) in the presence of 4,4′-bipyridine (4,4′-bpy) as a bridging nucleophile. The polymer films were characterized by electrochemical, spectroscopic (UV-Vis, XPS, FT-IR and Raman spectroscopy) and imaging (AFM and SEM) techniques. The absorption and electronic spectra confirm the presence of both porphyrin and 4,4′-bipyridine units in the film. The surface morphology reveals homogeneous film deposition with average roughness values of approx. 8 nm. The theoretical studies performed offered insights into the interplay of different metal centres (Zn2+ and Ni2+) and the keto functionality of the porphyrin unit in the formation of copolymer films. The electrochemical interaction of polymer films with CO2 suggests a reversible trap and release of CO2 with low energy barriers for both the polymers.Electropolymerization of keto functionalized porphyrins and 4,4′-bipyridine. 相似文献
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Ying Zhang Hanisha Ponnuru Qinting Jiang Hui Shan Hirbod Maleki Kheimeh Sari Wenbin Li Jingjing Wang Junhua Hu Jianhong Peng Xifei Li 《RSC advances》2022,12(16):9917
As a typical transition metal dichalcogenide (TMD), molybdenum disulphide (MoS2) has become one of the most promising anode materials for lithium-ion batteries (LIBs) due to its desirable electrochemical properties. But the development of commercial MoS2 is limited by the problem of agglomeration. Thus, the production of MoS2 nanosheets with few (<10) layers is highly desired but remains a great challenge. In this work, a facile and scalable approach is developed to prepare large-flake, few-layer (4–8) MoS2 nanosheets with the assistance of ultrasonics. Simultaneously, the as-prepared MoS2 nanosheets and commercial bulk MoS2 were analysed under multiple spectroscopic techniques and a series of electrochemical tests to understand the dependence of electrochemical performance on structural properties. When used as anode materials for LIBs, the obtained MoS2 nanosheets provide a reversible capacity of 716 mA h g−1 at 100 mA g−1 after 285 cycles, and demonstrated an excellent capacity retention rate of up to 80%. Compared with that of commercial MoS2 (14.8%), the capacity retention rate of our MoS2 nanosheets has a significant improvement. This work explored the ability of few-layered MoS2 nanosheets in the field of LIBs while suggesting the commercialization of the MoS2 by an ultrasonicated ball milling exfoliation technique.A facile and scalable approach is developed to prepare large-flake, few-layer (4–8) MoS2 nanosheets with the assistance of ultrasonics. 相似文献
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