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排序方式: 共有480条查询结果,搜索用时 203 毫秒
21.
Aída J. Velarde-Salcedo Alberto Barrera-Pacheco Samuel Lara-González Gabriela M. Montero-Morán Agustín Díaz-Gois Elvira González de Mejia Ana P. Barba de la Rosa 《Food chemistry》2013
Bioactive compounds present in foods could potentially have beneficial effects on human health. In this study we report the in vitro inhibitory capacity of peptides released from amaranth seed proteins after enzymatic digestion, against dipeptidyl peptidase IV (DPPIV); an enzyme known to deactivate incretins, hormones involved in insulin secretion. Other seeds, such as soybean, black bean, and wheat were also tested. The highest inhibition of DPPIV was observed with amaranth peptides released after simulated gastrointestinal digestion, showing an IC50 of 1.1 mg/mL in a dose-dependent manner. In silico tryptic digestion of amaranth globulins was carried out releasing peptides larger than 13 residues. Some of these peptides were used for the in silico prediction of their binding modes with DPPIV. Docking models showed that the possible mechanism of globulin peptides to inhibit DPPIV was through blocking the active dimer formation. Peptides were also found inside the major cavity where the natural substrates reach the catalytic site of the enzyme. This is the first report of the identification of inhibitory DPPIV peptides from amaranth hydrolysates and the prediction of their binding modes at the molecular level, leading to their possible use as functional food ingredients in the prevention of diabetes. 相似文献
22.
水系绿道 以米兰北部V'Arco Villoresi项目为例 总被引:1,自引:0,他引:1
以米兰北部的V’Arco Villoresi项目为例,探讨了水系绿道对协调各类用地的关系,提升公共土地的环境,保护水体,修复受损的生态环境,实现生态廊道的积极作用,并可为环境、景观和社区使用提供优质清洁的水源,并总结了项目在实施过程中得到的经验和遇到的障碍。 相似文献
23.
Elvira Sondo Federico Cresta Cristina Pastorino Valeria Tomati Valeria Capurro Emanuela Pesce Mariateresa Lena Michele Iacomino Ave Maria Baffico Domenico Coviello Tiziano Bandiera Federico Zara Luis J. V. Galietta Renata Bocciardi Carlo Castellani Nicoletta Pedemonte 《International journal of molecular sciences》2022,23(6)
Loss-of-function mutations of the CFTR gene cause cystic fibrosis (CF) through a variety of molecular mechanisms involving altered expression, trafficking, and/or activity of the CFTR chloride channel. The most frequent mutation among CF patients, F508del, causes multiple defects that can be, however, overcome by a combination of three pharmacological agents that improve CFTR channel trafficking and gating, namely, elexacaftor, tezacaftor, and ivacaftor. This study was prompted by the evidence of two CF patients, compound heterozygous for F508del and a minimal function variant, who failed to obtain any beneficial effects following treatment with the triple drug combination. Functional studies on nasal epithelia generated in vitro from these patients confirmed the lack of response to pharmacological treatment. Molecular characterization highlighted the presence of an additional amino acid substitution, L467F, in cis with the F508del variant, demonstrating that both patients were carriers of a complex allele. Functional and biochemical assays in heterologous expression systems demonstrated that the double mutant L467F-F508del has a severely reduced activity, with negligible rescue by CFTR modulators. While further studies are needed to investigate the actual prevalence of the L467F-F508del allele, our results suggest that this complex allele should be taken into consideration as plausible cause in CF patients not responding to CFTR modulators. 相似文献
24.
25.
Francesca Bugli Federica Massaro Francesco Buonocore Paolo Roberto Saraceni Stefano Borocci Francesca Ceccacci Cecilia Bombelli Maura Di Vito Rosalba Marchitiello Melinda Mariotti Riccardo Torelli Maurizio Sanguinetti Fernando Porcelli 《International journal of molecular sciences》2022,23(4)
The increasing resistance of fungi to antibiotics is a severe challenge in public health, and newly effective drugs are required. Promising potential medications are lipopeptides, linear antimicrobial peptides (AMPs) conjugated to a lipid tail, usually at the N-terminus. In this paper, we investigated the in vitro and in vivo antifungal activity of three short myristoylated and non-myristoylated peptides derived from a mutant of the AMP Chionodracine. We determined their interaction with anionic and zwitterionic membrane-mimicking vesicles and their structure during this interaction. We then investigated their cytotoxic and hemolytic activity against mammalian cells. Lipidated peptides showed a broad spectrum of activity against a relevant panel of pathogen fungi belonging to Candida spp., including the multidrug-resistant C. auris. The antifungal activity was also observed vs. biofilms of C. albicans, C. tropicalis, and C. auris. Finally, a pilot efficacy study was conducted on the in vivo model consisting of Galleria mellonella larvae. Treatment with the most-promising myristoylated peptide was effective in counteracting the infection from C. auris and C. albicans and the death of the larvae. Therefore, this myristoylated peptide is a potential candidate to develop antifungal agents against human fungal pathogens. 相似文献
26.
Abstract The aim of this work is to model the drying kinetics of mushrooms under several operational conditions, to evaluate the effective diffusivity coefficient of moisture removing by a drying model and inverse calculus method in finite differences and to study the effect on the final quality of dehydrated mushrooms. Different ways of microwave vacuum drying were compared to freeze-drying. Results show that a decrement of the applied pressure produces a certain increase in the drying rate together with a lower moisture in the dehydrated product at the end. Temperature control inside the sample helps to ensure a better quality in the dehydrated product, than when controlled at the surface. Diffusivity coefficients show a correspondence with product temperature during drying. The microwave dried samples obtained with moderate power and temperature control of product shown an important degree of quality similar to that obtained by freeze-drying. 相似文献
27.
Rodrigo F. P. Martins Arman Ahnood Nuno Correia Luís M. N. P. Pereira Raquel Barros Pedro M. C. B. Barquinha Ricardo Costa Isabel M. M. Ferreira Arokia Nathan Elvira E. M. C. Fortunato 《Advanced functional materials》2013,23(17):2153-2161
The ability to process and dimensionally scale field‐effect transistors with and on paper and to integrate them as a core component for low‐power‐consumption analog and digital circuits is demonstrated. Low‐temperature‐processed p‐ and n‐channel integrated oxide thin‐film transistors in the complementary metal oxide semiconductor (CMOS) inverter architecture are seamlessly layered on mechanically flexible, low‐cost, recyclable paper substrates. The possibility of building these circuits using low‐temperature processes opens the door to new applications ranging from smart labels and sensors on clothing and packaging to electronic displays printed on paper pages for use in newspapers, magazines, books, signs, and advertising billboards. Because the CMOS circuits reported constitute fundamental building blocks for analog and digital electronics, this development creates the potential to have flexible form factor computers seamlessly layered onto paper. The holistic approach of merging low‐power circuitry with a recyclable substrate is an important step towards greener electronics. 相似文献
28.
Alberto García‐Peñas José M Gómez‐Elvira María U de la Orden María L Cerrada Ernesto Pérez 《Polymer International》2016,65(5):596-604
The influence of crystallization rate on the interesting polymorphism of random isotactic poly(propylene‐co‐1‐heptene) copolymers was studied, with particular attention to the conditions for obtaining the mesomorphic phase. Owing to the important decrease of cooling rate involved as the 1‐heptene content increases, the mesophase can be clearly observed by DSC for co‐unit contents above about 5 mol%. Furthermore, only the mesophase (or the amorphous phase) was found for the copolymer with 13.9 mol% 1‐heptene at common cooling rates of the calorimeter. Additionally, the copolymer with 21.4 mol% co‐units was found to be completely amorphous under any thermal treatment analyzed. Variable‐temperature diffraction experiments were carried out to ascertain unambiguously the nature of the phases involved. Finally, a remarkable transparency was attained (above 80% transmittance in the visible light region) at intermediate and high 1‐heptene contents, using easily accessible cooling rates. © 2016 Society of Chemical Industry 相似文献
29.
Fire-fighters, paramedics, and emergency medical technicians routinely confront potentially traumatic events in the course of their jobs. The mediation role of coping strategies and collective efficacy in the relationship between stress appraisal and quality of life was examined (compassion satisfaction, compassion fatigue, and burnout) in a correlational study. Participants were 463 Italian rescue workers (fire fighters and different categories of emergency health care professionals). Participants filled out measures of stress appraisal, collective efficacy, coping strategies, and quality of life. The results showed that emotion and support coping, self-blame coping, and self-distraction mediated the relationship between stress appraisal and compassion fatigue. Moreover, collective efficacy, self-blame coping, and religious coping mediated the relationship between stress appraisal and burnout. Finally, collective efficacy, self-blame coping, and problem-focused coping mediated the relationship between stress appraisal and compassion satisfaction. Cognitive restructuring and denial did not mediate the relation between stress appraisal and any of the quality of life dimensions. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
30.