PubMed | Institute Higiene, Hospital Of Clinicas and UdelaR
Type: Journal Article | Journal: Parasitology research | Year: 2016
Fasciolosis, caused by the liver fluke Fasciola hepatica, is a major parasitic disease of livestock that causes significant economic losses worldwide. Although drugs are effective against liver flukes, they do not prevent reinfection, and continuous treatment is costly. Moreover, resistant fluke strains are emerging. In this context, vaccination is a good alternative since it provides a cost-effective long-term prevention strategy to control fasciolosis. In this paper, we evaluate the Fhmuc peptide as a potential vaccine against fasciolosis. This peptide derives from a mucin-like protein highly expressed in the infective stage of Fasciola hepatica. Mucin-like molecules expressed by parasites can contribute to several infection processes by protecting the parasite from host proteases and recognition by the immune system. We show that the Fhmuc peptide induces Th1-like immune responses specific for F. hepatica excretion-secretion products (FhESP) with a high production of IFN. We also investigated whether this peptide could protect animals from infection, and present preliminary data indicating that animals treated with Fhmuc exhibited reduced liver damage compared to non-immunised animals and that this protection was associated with a recruitment of B and T lymphocytes in the peritoneum, as well as eosinophils and mature dendritic cells. These results suggest that the mucin-like peptide Fhmuc could constitute a potential vaccine candidate against fasciolosis and pave the way towards the development of vaccines against parasites.
Rodriguez E.,Laboratory of Immunomodulation and Vaccine Development |
Noya V.,Laboratory of Immunomodulation and Vaccine Development |
Cervi L.,National University of Cordoba |
Chiribao M.L.,UdelaR |
And 4 more authors.
PLoS Neglected Tropical Diseases | Year: 2015
Helminths express various carbohydrate-containing glycoconjugates on their surface, and they release glycan-rich excretion/secretion products that can be very important in their life cycles, infection and pathology. Recent evidence suggests that parasite glycoconjugates could play a role in the evasion of the immune response, leading to a modified Th2-polarized immune response that favors parasite survival in the host. Nevertheless, there is limited information about the nature or function of glycans produced by the trematode Fasciola hepatica, the causative agent of fasciolosis. In this paper, we investigate whether glycosylated molecules from F. hepatica participate in the modulation of host immunity. We also focus on dendritic cells, since they are an important target of immune-modulation by helminths, affecting their activity or function. Our results indicate that glycans from F. hepatica promote the production of IL-4 and IL-10, suppressing IFNγ production. During infection, this parasite is able to induce a semi-mature phenotype of DCs expressing low levels of MHCII and secrete IL-10. Furthermore, we show that parasite glycoconjugates mediate the modulation of LPS-induced maturation of DCs since their oxidation restores the capacity of LPS-treated DCs to secrete high levels of the pro-inflammatory cytokines IL-6 and IL-12/23p40 and low levels of the anti-inflammatory cytokine IL-10. Inhibition assays using carbohydrates suggest that the immune-modulation is mediated, at least in part, by the recognition of a mannose specific-CLR that signals by recruiting the phosphatase Php2. The results presented here contribute to the understanding of the role of parasite glycosylated molecules in the modulation of the host immunity and might be useful in the design of vaccines against fasciolosis. © 2015 Rodríguez et al.
Diaz V.,Udelar |
Teliz E.,Udelar |
Ruiz F.,CONICET |
Ruiz F.,Bariloche Atomic Center |
And 3 more authors.
International Journal of Hydrogen Energy | Year: 2013
In the present investigation, the effect of the Mo in the LaNi 3,6Co0,7Mn(0.4-x)Al0,3Mo x AB5-type hydrogen storage alloys was studied. The alloys structural and microstructural characterizations were performed by means of X-ray diffraction phase analysis and scanning electron microscopy. The electrochemical properties were studied through the measurements of discharge capacity, activation process, rate capability and electrochemical impedance spectroscopy of the electrodes. The replacement of manganese by molybdenum, in the intermediate concentration tested (2% w/w) has a positive effect. This alloy presents the greatest discharge capacity, the closest potential to system equilibrium potential and therefore the lowest overpotentials. This alloy also has the best behavior for high-rate dischargeability and in concordance, the lowest charge transfer resistance. This improvement is thought to be due to an increase in the active area. © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Borteiro C.,Seccion Herpetologia |
Cruz J.C.,University of the Republic of Uruguay |
Kolenc F.,Seccion Herpetologia |
Manuel Verdes J.,University of the Republic of Uruguay |
And 5 more authors.
Journal of Wildlife Diseases | Year: 2014
We present gross and histologic evidence of coinfection in amphibians by fungal-like parasites of the order Dermocystidia (Amphibiocystidium sp.) and the fungus Batrachochytrium dendrobatidis. The condition was observed in frogs Hypsiboas pulchellus (Hylidae) from Uruguay in 2009 to 2012. This report is the first of dermocystids in Neotropical amphibians since 1940. © Wildlife Disease Association 2014.
PubMed | Queen's University of Belfast, University of Liverpool, UDELAR, University of Valencia and 2 more.
Type: Journal Article | Journal: Molecular & cellular proteomics : MCP | Year: 2015
Extracellular vesicles (EVs) released by parasites have important roles in establishing and maintaining infection. Analysis of the soluble and vesicular secretions of adult Fasciola hepatica has established a definitive characterization of the total secretome of this zoonotic parasite. Fasciola secretes at least two subpopulations of EVs that differ according to size, cargo molecules and site of release from the parasite. The larger EVs are released from the specialized cells that line the parasite gastrodermus and contain the zymogen of the 37 kDa cathepsin L peptidase that performs a digestive function. The smaller exosome-like vesicle population originate from multivesicular bodies within the tegumental syncytium and carry many previously described immunomodulatory molecules that could be delivered into host cells. By integrating our proteomics data with recently available transcriptomic data sets we have detailed the pathways involved with EV biogenesis in F. hepatica and propose that the small exosome biogenesis occurs via ESCRT-dependent MVB formation in the tegumental syncytium before being shed from the apical plasma membrane. Furthermore, we found that the molecular machinery required for EV biogenesis is constitutively expressed across the intramammalian development stages of the parasite. By contrast, the cargo molecules packaged within the EVs are developmentally regulated, most likely to facilitate the parasites migration through host tissue and to counteract host immune attack.
Casanova S.,University of the Republic of Uruguay |
Verdes J.M.,UdelaR |
Okada K.,Volunteer of Japan International Cooperation Agency JICA
Ciencia Rural | Year: 2014
The presence of Cryptosporidium spp. was detected in broiler chickens of 32-40 days of age, colonizing the bursa of Fabricius. The histologic study with haematoxylin and eosin staining was done on specimens of trachea, complete intestinal tract and bursa. Samples of intestinal content were also studied using Kinyoun staining technique. All birds with signs of illness were positive to the presence of parasite, showing a hypertrophic bursa of Fabricius, filled with caseous content. The bursal epithelial cells were full of different developmental stages of Cryptosporidium spp. This note describing the presence of Cryptosporidium spp. in industrial flocks of broiler chickens, is the first report of this parasite in Uruguay. © 2014, Universidade Federal de Santa Maria. All rights reserved.
PubMed | University of the Republic of Uruguay, Institute Mecanica Of Los Fluidos E Ingenieria Ambiental Imfia, CSIC - National Institute of Aerospace Technology, Centro Universitario Of La Region Este Cure Udelar and UDELAR
Type: | Journal: Environmental pollution (Barking, Essex : 1987) | Year: 2016
Beaches are social-ecological systems that provide several services improving human well-being. However, as one of the major coastal interfaces they are subject to plastic pollution, one of the most significant global environmental threats at present. For the first time for Uruguayan beaches, this study assessed and quantified the accumulation of plastic and microplastic debris on sandy beaches of the major touristic destination Punta del Este during the austral spring of 2013. Aiming to provide valuable information for decision-making, we performed a detailed analysis of plastic debris, their eventual transport pathways to the coast (from land and sea), and the associated persistent pollutants. The results indicated that the smallest size fractions (<20mm) were the dominant size range, with fragments and resin pellets as types with the highest number of items. PAHs and PCBs were found in plastic debris, and their levels did not differ from baseline values reported for similar locations. The abundance of plastic debris was significantly and positively correlated with both the presence of possible land-based sources (e.g. storm-water drains, beach bars, beach access, car parking, and roads), and dissipative beach conditions. The analysis of coastal currents suggested some potential deposition areas along Punta del Este, and particularly for resin pellets, although modeling was not conclusive. From a local management point of view, the development and use of indices that allow predicting trends in the accumulation of plastic debris would be critically useful. The time dimension (e.g. seasonal) should also be considered for this threat, being crucial for locations such as Uruguay, where the use of beaches increases significantly during the summer. This first diagnosis aims to generate scientific baseline, necessary for improved management of plastic litter on beaches and their watersheds.
Freire T.,UdelaR |
Freire T.,Institute Pasteur Montevideo |
Osinaga E.,UdelaR |
Osinaga E.,Institute Pasteur Montevideo
Immunotherapy | Year: 2012
Carbohydrate signatures on tumor cells have functional implications in tumor growth and metastasis and constitute valuable tools in cancer diagnosis and immunotherapy. Increasing data regarding the mechanisms by which they are recognized by the immune system are facilitating the design of more efficient immunotherapeutic protocols based on cancer-associated glycan structures. Recent molecular and proteomic studies revealed that carbohydrates are recognized, not only by B cells and antibodies, but also by cells from the innate arm of immunity, as well as by T cells, and are able to induce specific T-cell immunity and cytotoxicity. In this review, we discuss and update the different strategies targeting tumor-associated carbohydrate antigens that are being evaluated for antitumor immunotherapy, an approach that will be highly relevant, especially when combined with other strategies, in the future fight against cancer. © 2012 Future Medicine Ltd.
Bazerque J.A.,UTE |
Monzon P.,University of the Republic of Uruguay |
Pena P.,University of the Republic of Uruguay |
2015 IEEE PES Innovative Smart Grid Technologies Latin America, ISGT LATAM 2015 | Year: 2015
This paper advances a new method to predict trajectories of rotor angles and bus voltages in dynamic power systems, with data collected by phasor measurement units. The predictor incorporates real time data adaptively, leveraging the algebraic differential equations describing the system, while being able to accommodate model inaccuracies. Numerical tests on a one machine infinite bus system are carried out to illustrate the predictor properties. Then, further results are presented on a classical networked testbed of nine buses and three generators. © 2015 IEEE.
Aristoy G.,University of the Republic of Uruguay |
Isaurralde S.,University of the Republic of Uruguay |
Font E.,University of the Republic of Uruguay |
2015 IEEE PES Innovative Smart Grid Technologies Latin America, ISGT LATAM 2015 | Year: 2015
This article studies an algorithm for state estimation in electric power networks, adding information from phasor measurement units (PMU) to the classical SCADA data. This work describes the implementation in MatLab of one of the algorithms found in the literature and the migration of the code to C++ in order to test its time performance. The algorithm was tested on the 39 bus IEEE case study. A good tracking of the waveforms was achieved even in cases of three phase short-circuits or drastic load changes. Execution times obtained in C++ in regular desk computers where short enough to predict a suitable real time performance. © 2015 IEEE.