97 research outputs found

    Effectiveness of Educational Intervention with non-wax and Virtual Typodont Methods in Practical Orthodontic course of Dental Students, Shahid Beheshti University of Medical Sciences

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    Objectives Considering the educational value of non-wax and virtual typodonts, in this study, the results of the evaluation were compared to quantify each of the indicators in the evaluation of knowledge, attitude, and performance. Methods All tenth-semester dental students were divided into 2 equal groups of 25 and were trained by two typodontists. A standard questionnaire with a Cronbach α of .830 was used to evaluate their knowledge and attitude, which was prepared based on a 7-point Likert scale. To analyze the data, the paired t test, independent t test, and analysis of covariance (ANOVA) were used with SPSS version 21. The significance level was set as 0.05. Results In each of the 2 educational methods, a significant increase in the overall score of the questionnaire completed by the students was observed after the educational intervention (P < 0.001).  Among the 17 questions related to students, only 1 question in the non-wax typodont group and 4 in the virtual typodont group did not show a significant effect of the intervention (P > 0.05). Conclusion Both typodonts had remarkable educational advantages and accounted for a large share of the points in the questionnaires. In cases where physical sense was important in education, non-wax typodont and in cases where spatial understanding of biomechanics was necessary in tooth movement, virtual typodont was superior

    Comparison of Properties of Breads Enriched with Omega-3 Oil Encapsulated in β-Glucan and Saccharomyces cerevisiae Yeast Cells

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      Background and objective: Flaxseed oil, as a potential source of polyunsaturated fatty acids, is susceptible to oxidation. Yeast cells of Saccharomyces cerevisiae and β-glucan can be used as biocompatible and biodegradable matrices for the protection of this nutritious oil from oxidation in foods enriched with omega-3 fatty acids. The aim of this study was to investigate quality properties of breads containing encapsulated and free flaxseed oils. Materials and methods: Flaxseed oil was encapsulated in either yeast cells or β-glucan. Functional wheat bread samples were prepared using unencapsulated and encapsulated flaxseed oils. These were compared with control samples in terms of dough rheological and bread quality parameters. Results and conclusion: Encapsulation significantly increased dough rheological properties (G′ and G″ values), firmness and density and decreased lightness, compared to control samples. Breads, containing flaxseed oil encapsulated in yeast cells, showed a lower peroxide index and a higher α-linolenic acid value, compared to two other samples containing oil samples. This showed a better protection of unsaturated fatty acids against deleterious oxidation reactions. Results of this study indicate that addition of microencapsulated flaxseed oil into breads helps preserve sensory properties of the control sample, compared to breads fortified with free flaxseed oil. Conflict of interest: The authors declare no conflict of interest

    Effects of Microbial Transglutaminase and Fermentation Type on Improvement of lysine Availability in Wheat Bread: A Response Surface Methodology

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    Background and objective: Lysine-glutamine crosslink formation catalyzed by microbial transglutaminase is supposed to affect improvement of lysine availability in wheat bread. Present study is done to investigate the effect of microbial transglutaminase and fermentation type in improvement of the lysine availability of wheat bread.Material and methods: Lysine-fortified wheat breads were formulated using response surface methodology with composite-face central design. Statistical models were used to predict the impact of defatted soy flour level (0-50% w w-1), microbial transglutaminase level (0-1.6% w w-1) and fermentation type (yeast or mixed fermentation based on sourdough). Further information was provided on the individual role of independent variables in nutritional and structural characteristics of optimized formulation and blank and control samples. Experiments were carried out in triplicate and the mean values were analyzed using one-way analysis of variance and Tukey’s test.Results and conclusion: The suggested formula contained 26.64% w w-1 of defatted soy flour and 0.55% w w-1 of microbial transglutaminase, which was fermented using sourdough-based mixed fermentation and provided 0.16 mg 100 g-1 of available lysine and 2.09 cm3 g-1 of specific volume. The highest lysine chemical score (22.79±0.16), essential amino acid index (35.31±0.37) and biological value (26.79±0.02) and the lowest lysine loss during the baking process seen in optimized formulation verified the effectiveness of microbial transglutaminase in lysine fortification of defatted soy flour/wheat breads (P≤0.05). Considering rheology parameters and textural analysis, microbial transglutaminase treatment increased elastic modulus and β-sheet structure. These structural changes decreased final products digestibility, which can increase using mixed fermentation based on sourdough.Conflict of interest: The authors declare no conflict of interest

    Electric field effects on proteins Novel perspectives on food and potential health implications

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    Electric fields (EF) technologies have been establishing a solid position in emergent food processing and have seen as serious alternatives to traditional thermal processing. During the last decades, research has been devoted to elucidation of technological and safety issues but also fundamental aspects related with interaction of electric fields (EF) with important macromolecules, such as proteins. Proteins are building blocks for the development of functional networks that can encompass health benefits (i.e. nutritional and bioactive properties) but may be also linked with adverse effects such as neurodegenerative diseases (amyloid fibrils) and immunological responses. The biological function of a protein depends on its tridimensional structure/conformation, and latest research evidences that EF can promote disturbances on protein conformation, change their unfolding mechanisms, aggregation and interaction patterns. This review aims at bringing together these recent findings as well as providing novel perspectives about how EF can shape the behavior of proteins towards the development of innovative foods, aiming at consumers health and wellbeing.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/ BIO/04469/2019 and UIDB 50006/2020 with funding from FCT/ MCTES through national funds, BioTecNorte operation (NORTE-01- 0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. This work was also supported by the projects AlleRiskAssess – PTDC/BAA-AGR/31720/2017 and NORTE-01-0145-FEDER-031720. Zita Avelar acknowledge the Foundation for Science and Technology (FCT) for its fellowship SFRH/BD/146347/2019info:eu-repo/semantics/publishedVersio

    Enhancing clenbuterol immunosensor based on poly(3,4-ethylenedioxythiophene)/multi-walled carbon nanotube performance by response surface methodology

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    Clenbuterol (CLB) is an illegal antibiotic for livestock, which is misused as a growth promoter drug. In this study, an immunosensor modified with poly(3,4-ethylenedioxythiophene) (PEDOT), multi-walled carbon nanotubes (MWCNT) and anti-clenbuterol antibody (Ab) was developed for the detection of CLB. A screen-printed carbon electrode (SPCE) was modified with PEDOT/MWCNT as a sensor platform before immobilizing Ab for specific CLB binding through a competitive-type immunoassay. Free CLB in the sample solution competed with clenbuterol-horseradish peroxide (CLB–HRP) to bind with Ab. A high current signal was obtained after optimization of the electrochemical immunoassay conditions (pH, incubation temperature, antigen (Ag) incubation time and % blocking) using the response surface methodology/central composite design (RSM/CCD). The developed immunosensor is highly reproducible and sensitive with good storage stability, which are necessary for practical application. In real sample application, this immunosensor produces comparable results with liquid chromatography-mass spectrometry; thus, it is useful for CLB screening and monitoring in real meat samples
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