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排序方式: 共有1253条查询结果,搜索用时 15 毫秒
81.
Fabio Forghieri Giovanni Riva Ivana Lagreca Patrizia Barozzi Francesca Bettelli Ambra Paolini Vincenzo Nasillo Beatrice Lusenti Valeria Pioli Davide Giusti Andrea Gilioli Corrado Colasante Laura Galassi Hillary Catellani Francesca Donatelli Annalisa Talami Rossana Maffei Silvia Martinelli Leonardo Potenza Roberto Marasca Enrico Tagliafico Rossella Manfredini Tommaso Trenti Patrizia Comoli Mario Luppi 《International journal of molecular sciences》2021,22(17)
The C-terminal aminoacidic sequence from NPM1-mutated protein, absent in normal human tissues, may serve as a leukemia-specific antigen and can be considered an ideal target for NPM1-mutated acute myeloid leukemia (AML) immunotherapy. Different in silico instruments and in vitro/ex vivo immunological platforms have identified the most immunogenic epitopes from NPM1-mutated protein. Spontaneous development of endogenous NPM1-mutated-specific cytotoxic T cells has been observed in patients, potentially contributing to remission maintenance and prolonged survival. Genetically engineered T cells, namely CAR-T or TCR-transduced T cells, directed against NPM1-mutated peptides bound to HLA could prospectively represent a promising therapeutic approach. Although either adoptive or vaccine-based immunotherapies are unlikely to be highly effective in patients with full-blown leukemia, these strategies, potentially in combination with immune-checkpoint inhibitors, could be promising in maintaining remission or preemptively eradicating persistent measurable residual disease, mainly in patients ineligible for allogeneic hematopoietic stem cell transplant (HSCT). Alternatively, neoantigen-specific donor lymphocyte infusion derived from healthy donors and targeting NPM1-mutated protein to selectively elicit graft-versus-leukemia effect may represent an attractive option in subjects experiencing post-HSCT relapse. Future studies are warranted to further investigate dynamics of NPM1-mutated-specific immunity and explore whether novel individualized immunotherapies may have potential clinical utility in NPM1-mutated AML patients. 相似文献
82.
Stevioside, a potent sweetener obtained from leaves of Stevia rebaudiana (Bertoni), is the glycone of steviol. However, despite its natural origin, there has been concern about stevioside toxicity due to hydrolysis to the carcinogenic steviol. To approve it as an additive, the FAO/WHO committee on food additives has required further information about hydrolytic stability of the steviol glycoside in acidic foods and beverages. In this study, aqueous solutions of stevioside at different pH values were monitored in real time by direct infusion ESI-MS. Owing to the high speed and sensitivity of ESI-MS monitoring, fast hydrolysis of the stevioside molecule to steviol in aqueous acidic solutions was observed, particularly in acidic juices. 相似文献
83.
Ronaldo C. Gurgel‐Loureno Leonardo M. Pinto Luis A. V. Bezerra Jorge I. Snchez‐Botero 《河流研究与利用》2020,36(7):1353-1359
Several fish species from Central America and other regions have been introduced into Brazil. In this study, we evaluated the bioecological aspects of a non‐native cichlid of the genus Amatitlania (convict cichlid) and its possible establishment in high‐altitude forest enclaves of semi‐arid Northeastern Brazil. Specimens of Amatitlania nigrofasciata (Günther, 1867) were captured in a local stream displaying abiotic conditions like those of its natural range of distribution. The individuals collected were predominantly adult, insectivorous and displayed normal length–weight relationships, although we observed some phenotypical plasticity (variation in body depth, and a morphologically abnormal dorsal fin in three cases). Our results indicate that A. nigrofasciata has successfully colonized an Atlantic forest enclave in the Brazilian semi‐arid region, making it necessary to adopt measures to prevent the species from spreading to other water bodies in the surroundings. 相似文献
84.
85.
Karolien Verhaegen Leonardo Meeus Ronnie Belmans 《Renewable & Sustainable Energy Reviews》2009,13(1):208-215
In Europe, a common framework for renewable energy sources (RES) is aspired. Tradable green certificates (TGCs) are a market-based cost-efficient means to stimulate electricity production from RES. Since TGCs are the most widespread support scheme in Europe together with feed-in tariffs, chances are that a common European framework could well be based on TGCs. However, while integrating currently existing different national TGC systems, any remaining differences should be carefully considered. Just how difficult the creation of an international TGC market would be is illustrated in this paper by the case of Belgium, where no less than 4 different TGC systems exist nowadays. The example of Belgium illustrates that harmonizing different TGC systems is easier said than done and represents a serious challenge. This clearly illustrates that a single European support scheme for RES, however desirable, is still far in the future. 相似文献
86.
Heloiza Vieira Rodrigues Pereira Karina Peixoto Saraiva Lucia Maria Jaeger Carvalho Leonardo Rodrigues Andrade Cristiana Pedrosa Anna Paola Trindade Rocha Pierucci 《Food research international (Ottawa, Ont.)》2009,42(1):115-121
This study evaluated the use of pea (Pisum sativum) and cowpea (Vigna unguiculata) protein isolates (PPI and CPI) in the microencapsulation of ascorbic acid (AA), by spray drying. PPI and CPI were used pure or mixed with maltodextrin (M) as wall materials of AA. The process yield was improved from 66% to 86% by the addition of M (CPI/M and PPI/M); also, AA particles yield was 79%. The AA retention from the drying process was higher in PPI/M (69%) than in CPI/M (66%), and this was attributed to PPI proteolysis profile, demonstrated by the SDS–PAGE electrophoresis. Scanning electron microscopy revealed that AA particles were similarly spherical and shriveled. Mean particle sizes of PPI/M/AA and CPI/M/AA were 7 and 8 μm, respectively. This study showed the exploration of protein isolates from legumes in the development of a microparticulate system containing AA with great potential for use in human health. 相似文献
87.
Occurrence patterns of alien freshwater turtles in a large urban pond ‘Archipelago’ (Rome,Italy): Suggesting hypotheses on root causes 下载免费PDF全文
Maria Paola Di Santo Leonardo Vignoli Giuseppe M. Carpaneto Corrado Battisti 《Lakes & Reservoirs: Research and Management》2017,22(1):56-64
The patterns of the occurrence and distribution of alien freshwater turtle species in an urban pond archipelago (Rome, Italy) were analysed, with the aim of exploring the role of a set of factors (type of ponds, landscape context, size area, distance from the nearest road) with a generalized linear model approach. A total of 311 ponds subdivided in three types (fountains, small basins, lakes) embedded in different landscape contexts (public parks, private parks, urban areas) at differing distances from the nearest road were sampled. Six non‐native freshwater turtle species in 31 sites were recorded (9.97%). Lakes exhibited the highest occurrence rates of alien freshwater turtles, compared to small basins and fountains. Freshwater turtle species in urbanized areas were only observed in parks (both public and private). In both the public and private parks, the lakes exhibited the highest percentage of occupied sites, with fountains being the lowest. A direct and significant relationship was observed between pond size and species richness. The distance from the nearest road did not appear to affect species richness. A first interpretation of the data from this study facilitated the postulation of two a posteriori hypotheses that should be tested, as follows: (i) the causal process of turtle release is random, and the rate of extinction (and recapture) is higher in smaller ponds, thus producing the observed pattern; and (ii) the turtle release is not random, and people actively select the ponds they consider more suitable for their pet animals. In this study, it appears the lakes were perceived by those who abandon their pets as the most ecologically suitable habitats among other pond types to accommodate the different species of turtles. Knowledge of people's attitudes in regard to releasing pet animals also might assist managers of public green spaces to develop strategies aimed to preserve local biodiversity, and to educate the public about the conservation issue represented by the alien species. 相似文献
88.
Monica Scordino Francesco Lazzaro Marco A. Borzì Leonardo Sabatino Pasqualino Traulo Giacomo Gagliano 《Food Additives and Contaminants: Part B: Surveillance Communications》2018,11(1):75-81
This paper reports the occurrence of dehydroacetic acid in cheese and cheese coatings collected in Italy during Agricultural Ministry Official control. Dehydroacetic acid is an antimicrobial substance not allowed to be used in EU countries as a food additive, with unknown effects on human health. Dehydroacetic acid was measured by a validated HPLC method according to Commission Decision 2002/657/EC criteria in terms of specificity, linearity, precision and accuracy, limit of detection, and limit of quantification. The method was successfully applied to 129 samples of commercial cheese coatings and related treated cheeses collected in Italy during 2017. The overall results demonstrated that about 40% of the investigated cheese coatings contained dehydroacetic acid, ranging from 0.010% to 2.5% w/w, evidencing illicit employment of this substance. Moreover, about 25% of treated cheeses contained dehydroacetic acid, from 5 to 250 mg/Kg, proving transfer of this substance from crust to cheese. 相似文献
89.
Tiago Augusto Catelani Dayana Borges Bittar Leonardo Pezza Helena Redigolo Pezza 《Food Analytical Methods》2016,9(9):2552-2559
This paper describes the development of a rapid and clean method for the determination of hydrolysable tannins in honey samples, focusing on an easy and green sample pretreatment and low generation of waste. The proposed method is based on the reaction between KIO3 and hydrolysable tannin compounds in acetate buffer medium (pH 4.75), with formation of a colored product measured at 525 nm. The analytical conditions were optimized using experimental design (central composite design). The linear range obtained was 40.0–740 mg L?1 (r?=?0.998), and the detection (LOD) and quantification (LOQ) limits were 12.2 and 40.8 mg L?1, respectively. Acetate buffer was used to ensure formation of the colored product obtained by reaction between the chromogenic reagent and the analyte. The method showed good results when applied to honey samples, with recoveries in the range of 78.3–96.1 %, and the use of diffuse reflectance spectroscopy coupled with spot test analysis provided low reagent consumption and minimized waste generation. The results obtained with the proposed method were confirmed by a spectrophotometric method. 相似文献
90.
Leonardo Dallegrave Afonso Viviana Cocco Mariani Leandro dos Santos Coelho 《Expert systems with applications》2013,40(9):3794-3802
System reliability analysis and optimization are important to efficiently utilize available resources and to develop an optimal system design architecture. System reliability optimization has been solved by using optimization techniques including meta-heuristics. Meanwhile, the development of meta-heuristics has been an active research field of the reliability optimization wherein the redundancy, the component reliability, or both are to be determined. In recent years, a broad class of stochastic meta-heuristics, such as simulated annealing, genetic algorithm, tabu search, ant colony, and particle swarm optimization paradigms, has been developed for reliability-redundancy optimization of systems. Recently, a new kind of evolutionary algorithm called Imperialist Competitive Algorithm (ICA) was proposed. The ICA is based on imperialistic competition where the populations are represented by countries, which are classified as imperialists or colonies. However, the trade-off between the exploration (i.e. the global search) and the exploitation (i.e. the local search) of the search space is critical to the success of the classical ICA approach. An improvement in the ICA by implementing an attraction and repulsion concept during the search for better solutions, the AR-ICA approach, is proposed in this paper. Simulations results demonstrates the AR-ICA is an efficient optimization technique, since it obtained promising solutions for the reliability redundancy allocation problem when compared with the previously best-known results of four different benchmarks for the reliability-redundancy allocation problem presented in the literature. 相似文献