Although gut diseases such as inflammatory bowel disease, mucositis and the alimentary cancers share similar pathogenetic features, further investigation is required into new treatment modalities. An ...imbalance in the gut microbiota, breached gut integrity, bacterial invasion, increased cell apoptosis to proliferation ratio, inflammation and impaired immunity may all contribute to their pathogenesis. Probiotics are defined as live bacteria, which when administered in sufficient amounts, exert beneficial effects to the gastrointestinal tract. More recently, probiotic-derived factors including proteins and other molecules released from living probiotics, have also been shown to exert beneficial properties. In this review we address the potential for probiotics, with an emphasis on probiotic-derived factors, to reduce the severity of digestive diseases and further discuss the known mechanisms by which probiotics and probiotic-derived factors exert their physiological effects.
Mucositis, characterized by ulcerative lesions along the alimentary tract, is a common consequence of many chemotherapy regimens. Chemotherapy negatively disrupts the intestinal microbiota, resulting ...in increased numbers of potentially pathogenic bacteria, such as Clostridia and Enterobacteriaceae, and decreased numbers of "beneficial" bacteria, such as Lactobacilli and Bifidobacteria. Agents capable of restoring homeostasis in the bowel microbiota could, therefore, be applicable to mucositis. Prebiotics are indigestible compounds, commonly oligosaccharides, that seek to reverse chemotherapy-induced intestinal dysbiosis through selective colonization of the intestinal microbiota by probiotic bacteria. In addition, evidence is emerging that certain prebiotics contribute to nutrient digestibility and absorption, modulate intestinal barrier function through effects on mucin expression, and also modify mucosal immune responses, possibly via inflammasome-mediated processes. This review examines the known mechanisms of prebiotic action, and explores their potential for reducing the severity of chemotherapy-induced mucositis in the intestine.
Reliable techniques for the cryopreservation of both sperm and oocytes of the blue mussel
Mytilus galloprovincialis
Lamarck would increase the availability of seed supplies out-of-season and enhance ...efficiency in selective breeding. We have investigated the optimal cryo-technique for blue mussel oocytes. The toxicity of three cryoprotective agents (CPAs) dimethyl sulfoxide (DMSO), ethylene glycol (EG) and propylene glycol (PG) at different concentrations (1–5 M) and exposure times (0.25–30 min) were investigated for mussel oocytes at room temperature (20 °C) or on ice. The same CPAs (1, 1.5 and 2 M) as well as three different cryoprotectant mixtures 1.5 M EG + 0.2 M trehalose + 100 % Milli-Q water (EGTM); 1.5 M EG + 0.2 M trehalose + 75 % Milli-Q water + 25 % seawater; 1.5 M EG + 0.2 M sucrose + 100 % Milli-Q water were tested by comparing the post-thaw oocyte fertilization rate after using the slow-cooling method. Vitrification was also examined; however, this method failed to produce any post-thaw surviving oocytes. Among the tested CPAs, EG was the least toxic to oocytes. There was a tendency for the equilibration of CPAs on ice to achieve a higher oocyte fertilization rate compared with that at room temperature, and this difference was significant at concentrations of 3 and 4 M (
P
< 0.01). The DMSO, EG and PG treatments all resulted in post-thaw fertilization, with EGTM achieving the highest number of surviving oocytes (32 %). At the optimal seeding temperature (−7 °C), the addition of 0.2 M trehalose to EG resulted in a better fertilization rate of post-thawed oocytes than the addition of 0.2 M sucrose. All of the treatments evaluated produced D-larvae from post-thawed oocytes, although the rates were low.
With the explosion of information, recommendation systems have become important for users to find their interested information. Existing recommendation methods mainly utilize user historical ...interaction with items or user ratings to capture user past preferences. However, there is ignorance of various personalized reasons for users preferring an item, in which the reasons always dominate users’ preference strengths on the item. In addition, the linear nature of traditional recommendation methods makes them less effective in dealing with complex data. With the development of deep learning methods, graph neural networks provide an unprecedented opportunity for recommendations, since the user-item interactions can be naturally represented as a graph and the method can extract high-order complex relationships between users and items. In this paper, we propose a novel method leveraging the
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ne-
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rained user preferences with
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raph
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eural
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etworks (FigGNN) for recommendation to tackle these issues. More specifically, user-item interactions with user annotated tags and user ratings are constructed as a graph. In the process of graph message propagation, the user annotated tags are incorporated for understanding user preference reasons on items, and heterogeneous user rating levels are utilized for recognizing user preference strengths on items. Experiments have been conducted on the MovieLens dataset and the results show a superior performance of FigGNN over baselines in terms of precision and recall, which demonstrates the effectiveness of the proposed method.
In recent years, the establishment of a substantial amount of academic groups on scientific social network has brought new opportunities for the collaboration among researchers. In this situation, ...conducting paper recommendation to these academic groups is of terrific necessity in that it can further facilitate group activities. However, when producing group recommendation, existing methods fail to make full use of the abundant group information, from which a great deal of valuable information can be inferred to facilitate the recommendation performance. In addition, those methods tend to assign an equal weight to each group member when aggregating their recommendations, which is unreasonable in practice. Although some improvements have been made to remedy this problem by assigning different weights to group members, they fail to take into account the reliabilities of group members. Therefore, a group-oriented paper recommendation method based on probabilistic matrix factorization and evidential reasoning (GPMF_ER) is proposed in this article to tackle these problems. More specifically, the group and paper content information are integrated into the probabilistic matrix factorization model to enhance the accuracy of individual recommendation. Afterward, evidential reasoning rule is introduced in the aggregation step to consider both the weights and reliabilities of group members. Extensive experiments have been conducted on the real world CiteULike dataset and the results demonstrate the effectiveness of the proposed method.
Faecalibacterium prausnitzii (Fp) and Escherichia coli Nissle 1917 (EcN) are probiotics, which have been reported to ameliorate certain gastrointestinal disorders. We evaluated the effects of ...supernatants (SN) derived from Fp and EcN on 5-fluorouracil (5-FU)-treated intestinal cells and in a rat model of mucositis. In vitro: IEC-6, Caco-2, and T-84 cells were analyzed for viability and monolayer permeability. In vivo: Female dark agouti rats were gavaged with Fp or EcN SN and injected intraperitoneally with saline (control) or 5-FU to induce mucositis. Rats were euthanized and intestinal tissues collected for myeloperoxidase assay and histological analyses. In vitro: Caco-2 cell viability was further reduced when treated with Fp SN + 5-FU compared to 5-FU controls. In both Caco-2 and T-84 cells, Fp SN partially prevented the decrease in transepithelial electrical resistance (TER) caused by 5-FU administration. In vivo: 5-FU-injected rats administered Fp SN or EcN SN partly prevented body weight loss and normalized water intake compared to 5-FU controls. These results suggest a growth inhibitory mechanism of Fp SN action on transformed epithelial cells that could be mediated by effects on tight junctions. Factors derived from Fp SN and EcN SN could have a role in reducing the severity of intestinal mucositis.
Proteases, lipases and carbohydrases are digestive enzyme sub-classes that influence the digestive capacity of abalone. In a 12-week study, the effects of age, water temperature and dietary protein ...levels on digestive enzyme activity in greenlip abalone (Haliotis laevigata) were investigated. One- and 2-year old abalone were fed diets with crude protein (CP) levels from 24 to 36% (18.0–28.6% digestible protein) and cultured at 14, 18 and 22°C. Diets were formulated to be isoenergetic (12.5MJkg−1 digestible energy) and isolipidic (3.6% crude lipid). Trypsin, α-amylase and lipase activities were measured, and were influenced differently by abalone age, water temperature and dietary protein levels. Lipase and α-amylase activities significantly increased as water temperatures were raised. In contrast, trypsin activity was not affected by water temperature. Trypsin activity of 2-year old abalone was significantly lower (53%) than that of 1-year old abalone. The α-amylase activities of 1-year old abalone were significantly up-regulated as dietary protein levels increased. In contrast, 2-year old abalone down-regulated α-amylase activity by 55% when fed 33% CP, compared to abalone fed 30% CP. The significant trypsin activity down-regulation in 2-year old abalone compared to 1-year old animals provides further support to reducing dietary protein for 2-year old abalone to optimise cultured greenlip abalone production. Significantly higher α-amylase activity in 1-year old abalone as starch levels were reduced indicates a compensatory effect in abalone fed carbohydrate deficient diets. Further research is recommended to optimise the protein to energy ratio for different age classes of greenlip abalone, especially when fed high dietary protein levels.
Statement of relevance: Results may contribute to further diet development research
•Abalone enzyme activities were influenced differently by age, temperature and protein levels.•Trypsin activities of 2-year old abalone were significantly lower (53%) than 1-year old abalone.•Results may contribute to further diet development research for greenlip abalone.
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