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Ana Laura CIMADOR Emeli Luciana GALANTE Lucila Ibel MUÑOZ Patricia Silvia ROMANO Antonella Denisse LOSINNO María Cristina VANRELL 《Biocell》2019,43(1):13-20
Trypanosoma rangeli and T. cruzi are both parasitic unicellular species that infect humans. Unlike T. cruzi,
the causative agent of Chagas disease, T. rangeli is an infective and non-pathogenic parasite for humans, but pathogenic
for vectors from the Rhodnius genus. Because both species can coexist in different hosts and overlap their infective
cycles but very little is known about the infection of T. rangeli in mammalian cells, we decided to characterize both the
development of this parasite in cell culture and the effect of therapeutic agents with potential trypanocidal action on
it. We found that T. rangeli exhibits a cycle of infection in Vero cells similar to that for T. cruzi and that the repurposed
drug, 17-AAG, and the natural extract Artemisia sp. essential oil produce a toxic effect on epimastigotes showing
a trypanocidal action from the fifth day of culture. Both treatments also affected the infection of trypomastigotes
and reduced the capacity of replication of amastigotes of T. rangeli. Since T. cruzi / T. rangeli coinfection cases have
been reported, the finding of drugs with potential activity against both species could be significant in the future.
Furthermore, studies of susceptibility of both species to drugs could also help to know the different mechanisms of
pathogenicity in humans displayed by T. cruzi that are absent in T. rangeli 相似文献
104.
Alejandra Vesga-Baron Claudia Etchebehere M. Cristina Schiappacasse Rolando Chamy Estela Tapia-Venegas 《International Journal of Hydrogen Energy》2021,46(7):5074-5084
The oxidation-reduction potential (ORP) is an important factor in H2 production via dark fermentation however its effect over microbial diversity in an acidogenic sludge has not, been well studied. This work studies the effect of ORP controlled by hydrogen peroxide and potassium ferricyanide on continuous hydrogen production and microbial diversity in an acidogenic sludge fed (HRT 12 h and pH 5.5) with glycerol. Results show that the more oxidizing ORP control environment (?540 mV) improves H2 yield by 50–70% (0.31–0.51 molH2/mol glycerol) over non-ORP control conditions. Oxidizing ORP values were shown to enrich microorganisms of the genus Clostridium, which have been linked to high H2 yields. Therefore, controlling ORP in an acidogenic sludge was shown to directly modify microbial diversity at the genus level, and could likely to indirectly regulate metabolic function. Additionally, metabolic pathways were regulated by the kind of agent used. 相似文献
105.
Cristina Porojan Simon M. Mitrovic Darren C. J. Yeo 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(10):1570-1586
Blue-green algae are responsible for the production of different types of toxins which can be neurotoxic, hepatotoxic, cytotoxic and dermatotoxic and that can affect both aquatic and terrestrial life. Since its discovery the neurotoxin β-methylamino-L-alanine (BMAA) has been a cause for concern, being associated with the neurodegenerative disease amyotrophic lateral sclerosis/Parkinsonism–dementia complex (ALS/PDC). The initial focus was on Guam where it was observed that a high number of people were affected by the ALS/PDC complex. Subsequently, researchers were surprised to find levels of BMAA in post mortem brains from Canadian patients who also suffered from ALS/PDC. Recent research demonstrates that BMAA has been found at different levels in the aquatic food web in the brackish waters of the Baltic Sea. There is emerging evidence to suggest that sand-borne algae from Qatar can also contain BMAA. Furthermore, there is now concern because BMAA has been found not only in warmer regions of the world but also in temperate regions like Europe. The aim of this review is to focus on the methods of extraction and analysis of the neurotoxic non-protein amino acid BMAA. We also consider the neurotoxicity, aetiology, and diverse sources and routes of exposure to BMAA. In recent years, different methods have been developed for the analysis of BMAA. Some of these use HPLC-FD, UPLC-UV, UPLC-MS and LC-MS/MS using samples that have been derivatised or underivatised. To date the LC-MS/MS approach is the most widely used analytical technique as it is the most selective and sensitive method for BMAA determination. 相似文献
106.
Felipe Sánchez Carrillo Linda Saucier Cristina Ratti 《International Journal of Food Properties》2017,20(3):573-584
Thermal properties of duck fatty liver (foie gras), foie gras emulsion and fatty liver fat, as well as regular duck fat, were determined as a function of temperature. Density of foie gras and foie gras fat and emulsion at 20°C was measured as 947, 836, and 928 kg/m3, respectively. Differential scanning calorimetry thermograms for foie gras fat resulted in melting points ranging from –20 to 40°C. Values for the specific heat at 65°C for the fatty liver, its emulsion and fat, and duck fat were 1.79, 2.38, 1.71, and 2.48 J/g°C, respectively. Thermal conductivity of foie gras (organ) and its emulsion at 40°C was determined as 0.330 and 0.428 W/m°C, respectively. Mathematical models based on composition and temperature were developed for all the thermal properties obtained in this work. 相似文献
107.
Efficacy of non-thermal technologies and sanitizer solutions on microbial load reduction and quality retention of strawberries 总被引:1,自引:0,他引:1
Elisabete M.C. AlexandreTeresa R.S. Brandão Cristina L.M. Silva 《Journal of food engineering》2012,108(3):417-426
The effect of non-thermal technologies (ozone in aqueous solution, ultrasound and ultraviolet C radiation) and washings with chemical solutions (sodium hypochlorite and hydrogen peroxide) on safety and quality features of strawberries was studied. These treatments were applied before fruit storage at two different temperatures (4 and 15 °C). The overall impact on microbial loads (total mesophiles, and yeasts and moulds) and selected quality attributes (colour, firmness, pH, total anthocyanins and ascorbic acid content) was assessed.During storage under refrigerated temperature, washing with hydrogen peroxide solutions resulted in strawberries with lower microbial loads, when compared to the other treatments. However, it produced significant key quality attributes losses, such as colour and total anthocyanins content.The results presented show that ozone and ultrasound are promising alternatives to thermal treatments. The application of such technologies, before refrigerated storage of strawberries, allowed a satisfactory retention of all quality characteristics analysed, while being efficient in controlling microbial contamination. 相似文献
108.
Cristina Arruti 《国际通用系统杂志》2013,42(4):461-469
The search for “complexity signatures” in natural laws is a main concern for researchers working in many different fields, going from physics to biology. Very simple laws are able to produce unforeseen behaviors, and from their “simplicity” sometimes it is not possible to predict anything about the potential complexities they are able to produce when applied to random initial conditions. Here elementary cellular automata (ECA) are used to illustrate this idea. In fact, using a recently developed approach to establish a correspondence between ECA rules and logical functions that constitute their structure (logical spectra) we analyzed ECA groups represented by automata 120 and 164. The automaton governed by rule 120 generates complex patterns under certain random initial conditions, whereas the one corresponding to rule 164 is known as a simple law when it is evaluated at random initial conditions. However, slight changes in the initial conditions of both ECA produce dramatic “simplicity–complexity transitions”, as it is shown here. These examples show that complexity, even in very simple formal systems, results from a subtle interplay between the structure of the laws and the initial conditions. Moreover, they draw attention to the importance of investigating if analogous comportments hold in large-scale natural phenomena as the yet enigmatic genotype–phenotype mapping. 相似文献
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Cristina Jansen-Alves Karina F. Fernandes Michele M. Crizel-Cardozo Fernanda D. Krumreich Caroline D. Borges Rui C. Zambiazi 《Food and Bioprocess Technology》2018,11(7):1422-1436
Propolis presents several health benefits due to the presence of bioactive compounds, mainly phenolic compounds; however, its application in food is limited due to undesirable odor and low water solubility. The bioactive compounds are usually susceptible to degradation by exposure to light, heat, or oxygen or by interaction with other compounds, which may limit its biological activity. The study aimed the propolis extract microencapsulation using rice, pea, soybean, and ovoalbumin proteins as wall material by spray drying and to analyze their in vitro digestion. The propolis extract presented a high concentration of apigenin. Encapsulation efficiency was greater than 70%, and it was maintained the antioxidant activity of propolis (88% inhibition of DPPH for propolis extract and >?73% for the microparticles). The DSC, ATR-FTIR, and X-ray diffraction techniques confirmed the encapsulation. The microparticles showed different shapes, sizes, and physical characteristics. The microparticles encapsulated with pea protein could be used in formulations of Minas Frescal cheese due to the controlled released, whereas the other microparticles could be used in pudding formulations. 相似文献