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101.
Yuri Nagamine Urata Eduardo Carneiro de Lyra Maria Lucia Hirata Katayama Ricardo Alves Basso Paulo Eduardo Zuccolotto de Assis Ana Paula Torres Cardoso Rosimeire Aparecida Roela Suely Nonogaki João Carlos Guedes Sampaio Góes M. Mitzi Brentani Maria Aparecida Azevedo Koike Folgueira 《Clinical nutrition (Edinburgh, Scotland)》2014
102.
Renata Saraiva Guedes Chaiana Piovesan José Leopoldo Ferreira Antunes Fausto Medeiros Mendes Thiago Machado Ardenghi 《Quality of life research》2014,23(9):2521-2530
Purpose
It has been suggested that subjective measures of oral health are influenced by both individual and contextual characteristics. This study assessed the relationship between neighborhood and individual social networks and child oral health-related quality of life (COHRQoL).Methods
This study followed a cross-sectional design using a multistage sample of 478 children aged 1–5 years old. Caregivers completed the Brazilian version of the Early Childhood Oral Health Impact Scale (ECOHIS) and answered questions related to socioeconomic status and social network. The dental examination provided information on the prevalence of dental caries, dental trauma, and occlusion. Contextual social determinants included the presence of cultural community centers and of workers’ association in the neighborhood. Data analysis considered the total ECOHIS scores as the outcome and neighborhood/individual social networks as the independent variables. A multilevel Poisson regression model was used to investigate the association among individual and contextual characteristics and COHRQoL.Results
Total ECOHIS scores ranged from 0 to 41 (possible range 0–52). The mean ECOHIS score was low (mean = 1.8, SD = 3.9), and the functional domain presented the highest mean impact on COHRQoL (mean = 0.5, SD = 1.4). Following adjusted analysis, low household income, visiting a neighbor less than once a month, the presence of anterior open bite, dental trauma, and dental caries were identified as individual determinants of negative impact on a child’s quality of life. These variables remained associated with the outcome even after adding the contextual-level variables in the model. At the contextual level, the presence of community cultural centers was associated with overall mean ECOHIS score; higher impacts on COHRQoL were observed in those living in neighborhoods without cultural community centers.Conclusion
There is a significant association between individual and contextual social determinants and COHRQoL; unfavorable social conditions and poor socioeconomic status have a negative impact on caregiver reports of children’s oral health-related quality of life. 相似文献103.
104.
105.
Placebo controls play a critical role in the evaluation of any pharmacotherapy. This review surveys the placebo arm in 12 randomized controlled trials (RCTs) investigating burning mouth syndrome (BMS) and documents a positive placebo response in 6 of them. On average, treatment with placebos produced a response that was 72% as large as the response to active drugs. The lack of homogeneity in the use of placebos adds to the difficulty in comparing results and aggregating data. Future RCTs investigating BMS would benefit from larger sample sizes, adequate follow‐up periods, and use of a standard placebo. 相似文献
106.
Rodrigo Guedes de Amorim Soraya Coelho Leal Jan Mulder Nico H. J. Creugers Jo E. Frencken 《Clinical oral investigations》2014,18(1):117-124
Objectives
The aims of this study were to compare 2-year cumulative survival rates of amalgam and atraumatic restorative treatment (ART) restorations in primary molars and to investigate the determinants of the survival rate of restorations.Materials and methods
A controlled clinical trial using a parallel group design was carried out on 258 children aged 6–7 years old, allocated to two treatment groups: conventional restorative treatment using amalgam and ART using high-viscosity glass ionomer. A total of 364 amalgam restorations and 386 ART restorations were placed by three pedodontists in 126 and 158 children, respectively, and were evaluated after 0.5, 1, and 2 years. Restorations were placed in vital primary molars with neither pain nor signs of pulp involvement. The survival analysis was conducted using the proportional hazard rate regression model with frailty correction.Results
The 2-year cumulative survival rates for all amalgam (77.3 %) and ART (73.5 %) restorations were not statistically significantly different, but there was an effect of “type of surface” (single/multiple) and “cavity filling time” on the survival rates. Both amalgam and ART single-surface restorations had higher survival rates than multiple-surface restorations of the same material. Secondary caries was responsible for 36 and 38 % of failures in amalgam and ART restorations, respectively. Mean time for restoring all type of cavities with amalgam and ART restorations was 13.6 and 13.7 min, respectively.Conclusions
Amalgam and ART restorations presented similar survival rates over a 2-year period for all, single-surface, and multiple-surface restorations.Clinical relevance
In the cause of finding alternatives to amalgam, ART restorations using high-viscosity glass ionomer might be a suitable option for managing cavitated dentine carious lesions in vital primary molars. 相似文献107.
Chavee Laomeephol Marta Guedes Helena Ferreira Rui L. Reis Sorada Kanokpanont Siriporn Damrongsakkul Nuno M. Neves 《Journal of tissue engineering and regenerative medicine》2020,14(1):160-172
Silk fibroin (SF) hydrogels can be obtained via self‐assembly, but this process takes several days or weeks, being unfeasible to produce cell carrier hydrogels. In this work, a phospholipid, namely, 1,2‐dimyristoyl‐sn‐glycero‐3‐phospho‐(1′‐rac‐glycerol) sodium salt (DMPG), was used to induce and accelerate the gelation process of SF solutions. Due to the amphipathic nature and negative charge of DMPG, electrostatic and hydrophobic interactions between the phospholipids and SF chains will occur, inducing the structural transition of SF chains to the beta sheet and consequently a rapid gel formation is observed (less than 50 min). Moreover, the gelation time can be controlled by varying the lipid concentration. To assess the potential of the hydrogels as cell carriers, several mammalian cell lines, including L929, NIH/3T3, SaOS‐2, and CaSki, were encapsulated into the hydrogel. The silk‐based hydrogels supported the normal growth of fibroblasts, corroborating their cytocompatibility. Interestingly, an inhibition in the growth of cancer‐derived cell lines was observed. Therefore, DMPG‐induced SF hydrogels can be successfully used as a 3D platform for in situ cell encapsulation, opening promising opportunities in biomedical applications, such as in cell therapies and tissue regeneration. 相似文献
108.
109.
Snia Rocha Natlia Aniceto Rita C. Guedes Hlio M. T. Albuquerque Vera L. M. Silva Artur M. S. Silva Maria Luísa Corvo Eduarda Fernandes Marisa Freitas 《Nutrients》2022,14(2)
Glycogen phosphorylase (GP) is a key enzyme in the glycogenolysis pathway. GP inhibitors are currently under investigation as a new liver-targeted approach to managing type 2 diabetes mellitus (DM). The aim of the present study was to evaluate the inhibitory activity of a panel of 52 structurally related chromone derivatives; namely, flavonoids, 2-styrylchromones, 2-styrylchromone-related derivatives [2-(4-arylbuta-1,3-dien-1-yl)chromones], and 4- and 5-styrylpyrazoles against GP, using in silico and in vitro microanalysis screening systems. Several of the tested compounds showed a potent inhibitory effect. The structure–activity relationship study indicated that for 2-styrylchromones and 2-styrylchromone-related derivatives, the hydroxylations at the A and B rings, and in the flavonoid family, as well as the hydroxylation of the A ring, were determinants for the inhibitory activity. To support the in vitro experimental findings, molecular docking studies were performed, revealing clear hydrogen bonding patterns that favored the inhibitory effects of flavonoids, 2-styrylchromones, and 2-styrylchromone-related derivatives. Interestingly, the potency of the most active compounds increased almost four-fold when the concentration of glucose increased, presenting an IC50 < 10 µM. This effect may reduce the risk of hypoglycemia, a commonly reported side effect of antidiabetic agents. This work contributes with important considerations and provides a better understanding of potential scaffolds for the study of novel GP inhibitors. 相似文献
110.
目的:目前有关骨髓间充质干细胞向内皮细胞诱导分化的研究较少。本实验分离和培养人骨髓间充质干细胞,用带有VEGF165的质粒转染人骨髓间充质干细胞,探讨血管内皮生长因子对其体外诱导分化的作用。
方法:实验于2005—04/2006—04在吉林大学人兽共患病教育部重点实验室完成。取成人的已排除血液系统肿瘤疾病的新鲜骨髓(自愿提供),采用Percoll梯度分离培养骨髓间充质干细胞,于倒置显微镜下观察细胞形态变化和生长情况。原代细胞培养至增殖接近融合状态时,单克隆培养法分离传代培养,扩增骨髓间充质干细胞。采用流式细胞术检测细胞免疫学表型。在原核细胞大肠杆菌DH5α中复制扩增和提取,纯化、克隆pcDNA3.0-VEGF165质粒。用脂质体转染法转染骨髓间充质干细胞:应用流式细胞术检测诱导后骨髓间充质干细胞免疫学表型变化j并采用免疫荧光染色鉴定转染情况,并设质粒空载和未转染的骨髓间充质干细胞为对照。
结果:人骨髓间充质干细胞原代培养1周后,造血细胞消失,贴壁细胞体积增大,呈现梭形外观,有粗大的细胞突起伸出。2周后细胞融合成单层,梭形突起变长,排列有明显的方向性,细胞排列成旋涡状、网状、辐射状。流式细胞术显示,人骨髓间充质干细胞免疫学表型CD44、CD29阳性,CD34、CD31、CD45阴性。VEGF165诱导骨髓间充质千细胞后CD44表达明显降低,CD31明显升高。免疫荧光染色显示,用FITC标记后的VEGF抗体使细胞显现绿色荧光,用cy3标记的CD31抗体使细胞显现了红色荧光。
结论:转染后的骨髓间充质干细胞细胞表型发生明显转变,CD31表达率明显增高,呈现典型的内皮细胞的表型特征,这说明骨髓间充质干细胞具有向内皮细胞分化的潜能。 相似文献