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101.
Michele Brauner de Mello Patrícia da Silva Malheiros Adriano Brandelli Nádya Pesce da Silveira Márcia Monks Jantzen Amanda de Souza da Motta 《Probiotics and antimicrobial proteins》2013,5(1):43-50
Encapsulation may provide increased stability and antimicrobial efficiency to bacteriocins. In this work, the antilisterial peptide pediocin was encapsulated in nanovesicles prepared from partially purified soybean phosphatidylcholine. The maintenance of antimicrobial activity and properties of free and encapsulated pediocin was observed during 13 days at 4 °C, and after this period, the encapsulated pediocin retained 50 % its initial activity. The maintenance of the bioactive properties of free and encapsulated pediocin was observed against different species of Listeria, inhibiting Listeria monocytogenes, Listeria innocua and Listeria ivanovii. The size of vesicles containing pediocin was determined by dynamic light scattering as an average of 190 nm, with little change throughout the observation period. Polydispersity index values were around 0.201 and are considered satisfactory, indicating an adequate size distribution of liposomes. The efficiency of encapsulation was 80 %. Considering these results, the protocol used was appropriate for the encapsulation of this bacteriocin. Results demonstrate the production of stable nanoparticulate material. The maintenance of the properties of pediocin encapsulated in liposomes is fundamental to prospect the stability in different conditions of the food matrix. 相似文献
102.
Food web response to species loss has been investigated in several ways in the previous years. In binary food webs, species go secondarily extinct if no resource item remains to be exploited. In this work, we considered that species can go extinct before the complete loss of their resources and we introduced thresholds of minimum energy requirement for species survival. According to this approach, extinction of a node occurs whenever an initial extinction event eliminates its incoming links so it is left with an overall energy intake lower than the threshold value. We tested the robustness of 18 real food webs by removing species from most to least connected and considering different scenarios defined by increasing the extinction threshold. Increasing energy requirement threshold negatively affects food web robustness. We found that a very small increase of the energy requirement substantially increases system fragility. In addition, above a certain value of energy requirement threshold we found no relationship between the robustness and the connectance of the web. Further, food webs with more species showed higher fragility with increasing energy threshold. This suggests that the shape of the robustness–complexity relationship of a food web depends on the sensitivity of consumers to loss of prey. 相似文献
103.
Agostina Puppo Alexander Bello Anna Manfredi Giulia Cesi Elena Marrocco Michele Della Corte Settimio Rossi Massimo Giunti Maria Laura Bacci Francesca Simonelli Enrico Maria Surace Gary P. Kobinger Alberto Auricchio 《PloS one》2013,8(3)
Recombinant adeno-associated viral (AAV) vectors are known to safely and efficiently transduce the retina. Among the various AAV serotypes available, AAV2/5 and 2/8 are the most effective for gene transfer to photoreceptors (PR), which are the most relevant targets for gene therapy of inherited retinal degenerations. However, the search for novel AAV serotypes with improved PR transduction is ongoing. In this work we tested vectors derived from five AAV serotypes isolated from porcine tissues (referred to as porcine AAVs, four of which are newly identified) for their ability to transduce both the murine and the cone-enriched pig retina. Porcine AAV vectors expressing EGFP under the control of the CMV promoter were injected subretinally either in C57BL/6 mice or Large White pigs. The resulting retinal tropism was analyzed one month later on histological sections, while levels of PR transduction were assessed by Western blot. Our results show that all porcine AAV transduce murine and porcine retinal pigment epithelium and PR upon subretinal administration. AAV2/po1 and 2/po5 are the most efficient porcine AAVs for murine PR transduction and exhibit the strongest tropism for pig cone PR. The levels of PR transduction obtained with AAV2/po1 and 2/po5 are similar, albeit not superior, to those obtained with AAV2/5 and AAV2/8, which evinces AAV2/po1 and 2/po5 to be promising vectors for retinal gene therapy. 相似文献
104.
Gary G. Bennett Dori M. Steinberg Michele G. Lanpher Sandy Askew Ilana B. Lane Erica L. Levine Melody S. Goodman Perry B. Foley 《PloS one》2013,8(8)
Objective
Offering calories on restaurant websites might be particularly important for consumer meal planning, but the availability of and ease of accessing this information are unknown.Methods
We assessed websites for the top 100 U.S. chain restaurants to determine the availability of and ease of access to calorie information as well as website design characteristics. We also examined potential predictors of calorie availability and ease of access.Results
Eighty-two percent of restaurants provided calorie information on their websites; 25% presented calories on a mobile-formatted website. On average, calories could be accessed in 2.35±0.99 clicks. About half of sites (51.2%) linked to calorie information via the homepage. Fewer than half had a separate section identifying healthful options (46.3%), or utilized interactive meal planning tools (35.4%). Quick service/fast casual, larger restaurants, and those with less expensive entrées and lower revenue were more likely to make calorie information available. There were no predictors of ease of access.Conclusion
Calorie information is both available and largely accessible on the websites of America’s leading restaurants. It is unclear whether consumer behavior is affected by the variability in the presentation of calorie information. 相似文献105.
Stefano Forte Alfredo Pagliuca Eugenia T. Maniscalchi Rosario Gulino Giovanna Calabrese Lucia Ricci-Vitiani Roberto Pallini Michele Signore Rosalba Parenti Ruggero De Maria Massimo Gulisano 《PloS one》2013,8(12)
The term astrocytoma defines a quite heterogeneous group of neoplastic diseases that collectively represent the most frequent brain tumors in humans. Among them, glioblastoma multiforme represents the most malignant form and its associated prognosis is one of the poorest among tumors of the central nervous system. It has been demonstrated that a small population of tumor cells, isolated from the brain neoplastic tissue, can reproduce the parental tumor when transplanted in immunodeficient mouse. These tumor initiating cells are supposed to be involved in cancer development and progression and possess stem cell-like features; like their normal counterpart, these cells remain quiescent until they are committed to differentiation. Many studies have shown that the role of the tumor suppressor protein PTEN in cell cycle progression is fundamental for tumor dynamics: in low grade gliomas, PTEN contributes to maintain cells in G1 while the loss of its activity is frequently observed in high grade gliomas. The mechanisms underlying the above described PTEN activity have been studied in many tumors, but those involved in the maintenance of tumor initiating cells quiescence remain to be investigated in more detail. The aim of the present study is to shed light on the role of PTEN pathway on cell cycle regulation in Glioblastoma stem cells, through a cell differentiation model. Our results suggest the existence of a molecular mechanism, that involves DUB3 and WEE1 gene products in the regulation of Cdc25a, as functional effector of the PTEN/Akt pathway. 相似文献
106.
107.
Gianluca
E.M. Boari Giulia Chiarini Silvia Bonetti Paolo Malerba Gianluca Bianco Cristina Faustini Federico Braglia-Orlandini Daniele Turini Vittoria Guarinoni Michele Saottini Sara Viola Giulia Ferrari-Toninelli Giancarlo Pasini Cristina Mascadri Bianca Bonzi Paolo Desenzani Claudia Tusi Eros Zanotti Matteo Nardin Damiano Rizzoni 《Bioscience reports》2020,40(12)
The aim of the present study was to simultaneously assess several potential predictors of outcome (co-morbidity, previous and in-hospital treatment, radiologic Brixia score) in patients with COVID-19.This retrospective cohort study included 258 consecutive patients with confirmed COVID-19 admitted to a medical ward at Montichiari Hospital, Brescia, Italy from February 28th to April 30rd, 2020. Patients had SARS-CoV-2 related pneumonia with respiratory failure, and were treated with hydroxychloroquine and lopinavir plus ritonavir. In some patients, additional treatment with tocilizumab, dexamethasone and enoxaparin was adopted. Outcomes (death or recovery) were assessed at the end of the discharge period or at the end of the follow-up (August 2020).During hospitalization, 59 patients died, while 6 died after discharge. The following variables were demonstrated to be associated with a worse prognosis: Radiologic Brixia score higher than 8, presence at baseline of hypertension, diabetes, chronic obstructive pulmonary disease, heart disease, cancer, previous treatment with ACE-inhibitors or anti-platelet drugs. Anticoagulant treatment during hospital admission with enoxaparin at a dose higher than 4000 U once daily was associated with a better prognosis.In conclusion, our study demonstrates that some co-morbidities and cardiovascular risk factors may affect prognosis. The radiologic Brixia score may be a useful tool to stratify the risk of death at baseline. Anticoagulant treatment with enoxaparin might be associated to a clinical benefit in terms of survival in patients with COVID-19. 相似文献
108.
Vanessa Castelli Francesco Melani Claudio Ferri Michele d'Angelo Mariano Catanesi Davide Grassi Elisabetta Benedetti Antonio Giordano Annamaria Cimini Giovambattista Desideri 《Journal of cellular biochemistry》2020,121(12):4862-4869
Oxidative stress is considered the common effector of the cascade of degenerative events in many neurological conditions. Thus, in this paper we tested different nutraceuticals in H2O2 in vitro model to understand if could represent an adjuvant treatment for neurological diseases. In this study, nutraceuticals bacopa, lycopene, astaxanthin, and vitamin B12 were used alone or in combination in human neuronal differentiated SH-SY5Y cells upon hydrogen peroxide-induced injury and neuroprotective, neuronal death pathways were analyzed. The nutraceuticals analyzed were able to protect H2O2 cytotoxic effects, through increasing cell viability and proteins involved in neuroprotection pathways and restoring proteins involved in cell death pathways. On this basis, it is possible to propose the use of these compounds as dietary supplement for the prevention or as adjuvant to the only symptomatic treatments so far available for neurodegenerative diseases. 相似文献
109.
Irreversible prey diapause as an optimal strategy of a physiologically extended Lotka–Volterra model
Kateřina Staňková Alessandro Abate Maurice W. Sabelis 《Journal of mathematical biology》2013,66(4-5):767-794
We propose an optimal control framework to describe intra-seasonal predator–prey interactions, which are characterized by a continuous-time dynamical model comprising predator and prey density, as well as the energy budget of the prey over the length of a season. The model includes a time-dependent decision variable for the prey, representing the portion of the prey population in time that is active, as opposed to diapausing (a state of physiological rest). The predator follows autonomous dynamics and accordingly it remains active during the season. The proposed model is a generalization of the classical Lotka–Volterra predator–prey model towards non-autonomous dynamics that furthermore includes the effect of an energy variable. The model has been inspired by a specific biological system of predatory mites (Acari: Phytoseiidae) and prey mites (so-called fruit-tree red spider mites) (Acari: Tetranychidae) that feed on leaves of apple trees—its parameters have been instantiated based on laboratory and field studies. The goal of the work is to understand the decisions of the prey mites to enter diapause (a state of physiological rest) given the dynamics of the predatory mites: this is achieved by solving an optimization problem hinging on the maximization of the prey population contribution to the next season. The main features of the optimal strategy for the prey are shown to be that (1) once in diapause, the prey does not become active again within the same season and hence diapause is an irreversible process; (2) for the vast majority of parameter space, the portion of prey individuals entering diapause within the season does not decrease in time; (3) with an increased number of predators, the optimal population strategy for the prey is to start diapause earlier and to enter diapause more gradually. This optimal population strategy will be studied for its ESS properties in a sequel to the work presented in this article. 相似文献
110.
Anna Maria Di Giacomo Luana Calabrò Riccardo Danielli Ester Fonsatti Erica Bertocci Isabella Pesce Carolina Fazio Ornella Cutaia Diana Giannarelli Clelia Miracco Maurizio Biagioli Maresa Altomonte Michele Maio 《Cancer immunology, immunotherapy : CII》2013,62(6):1021-1028