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Microalgae are considered an efficient accumulator and promising source of Se for feed additive purposes. This study aimed at investigating, for the first time, the effect of phosphorus limitation on Se accumulation and uptake efficiency in N. oceanica. A range of phosphorus concentrations (0–2470 µM) were tested in either the presence or absence of sodium selenite (0, 5, 30 µM). Se accumulation was increased up to 16-fold and Se uptake efficiency was increased up to 3.6-fold under phosphorus growth-limiting concentrations. N. oceanica was then cultivated in a 1.8 L flat-panel photobioreactor in batch operation under two phosphorus growth-limiting concentrations (250 and 750 µM) where the accumulation of Se in the microalgal biomass, as well as its presence in the spent medium were analysed. This study is the first to investigate the effect of phosphorus limitation for increasing Se accumulation in microalgae, and to prevent the release of Se in wastewater.

Recent discoveries show that fungi can take up environmental RNA, which can then silence fungal genes through environmental RNA interference. This discovery prompted the development of Spray-Induced Gene Silencing (SIGS) for plant disease management. In this study, we aimed to determine the efficacy of SIGS across a variety of eukaryotic microbes. We first examined the efficiency of RNA uptake in multiple pathogenic and non-pathogenic fungi, and an oomycete pathogen. We observed efficient double-stranded RNA (dsRNA) uptake in the fungal plant pathogens Botrytis cinerea, Sclerotinia sclerotiorum, Rhizoctonia solani, Aspergillus niger, and Verticillium dahliae, but no uptake in Colletotrichum gloeosporioides, and weak uptake in a beneficial fungus, Trichoderma virens. For the oomycete plant pathogen, Phytophthora infestans, RNA uptake was limited, and varied across different cell types and developmental stages. Topical application of dsRNA targeting virulence-related genes in the pathogens with high RNA uptake efficiency significantly inhibited plant disease symptoms, whereas the application of dsRNA in pathogens with low RNA uptake efficiency did not suppress infection. Our results have revealed that dsRNA uptake efficiencies vary across eukaryotic microbe species and cell types. The success of SIGS for plant disease management can largely be determined by the pathogen RNA uptake efficiency.

This study aims to investigate radiolabeled Cefpodoxime Proxetil loaded chitosan (CP–CS) nanoparticles as nuclear imaging infection agent to Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli). The encapsulation efficiency of Cefpodoxime Proxetil was found 82 ± 2%. CP and CP–CS nanoparticles were radiolabeled with Tc-99 m. The radiochemical purity of 99mTc–CP and 99mTc–CP–CS nanoparticles were determined by RTLC as 89 ± 3% and 94 ± 2% respectively. In vitro bindings of 99mTc–CP–CS nanoparticles to S. aureus and E. coli were found higher than 99mTc–CP bindings. © 2020, Akadémiai Kiadó, Budapest, Hungary.

The effects of different concentrations of P and N, added separately or combined, on the Cr(III) accumulation capacity of P. stratiotes were studied. Plants and pond water with the addition of contaminant(s) were placed in plastic aquaria. Cr concentration was 5 mg L-1, while P and N concentrations were 5 mg L-1 or 10 mg L-1. Nutrient addition significantly favoured Cr removal and enhanced Cr translocation to leaves. In Cr treatments a high detritus formation from loss of root biomass was observed probably due to its toxicity. Cr was mainly accumulated in the detrital fraction, whereas P and N were retained fundamentally in leaves. A toxic effect was observed in the Cr+P10 and Cr+N10 treatments. These results could be applied to enhance Cr removal efficiency of constructed wetlands using P. stratiotes, where nutrient enrichment could be attained by treating sewage together with the industrial effluents. Fil: Di Luca, Gisela Alfonsina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Laboratorio de Química Analítica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Hadad, Hernán Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Laboratorio de Química Analítica; Argentina Fil: Mufarrege, María de Las Mercedes. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Laboratorio de Química Analítica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Maine, Maria Alejandra. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Laboratorio de Química Analítica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Sanchez, Gabriela Cristina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Laboratorio de Química Analítica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina

Faba bean (Vicia faba L.) is one of the most important food legumes grown in Morocco under rainfed conditions. This crop requires phosphorus (P) fertilizers to produce higher yields. However, many farmers use low quantities of P because of its cost and the risk of drought. Consequently, the use of varieties with high P use efficiency (PUE) can improve productivity and farmers' income under erratic conditions where the application of high amounts of P is not economically justified. The genetic variation of PUE among Moroccan faba bean varieties was studied under different levels of available phosphorus to orientate the choice of adapted varieties. Two experiments were conducted, under rainfed conditions, at the experiment station of Douyet (Morroco) in 2000-2001 (year 1) and 2002-2003 (year 2). In both years, four P treatments 0, 40, 80 and 120 kg P 2O 5 ha -1 as fertilizer and four faba bean varieties (G) were tested. In year 1, the varieties tested were Aguadulce, Defès, Karabiga and Lobab. The same varieties were used in year 2 with the exception of Aguadulce, which was replaced by a determinate genotype with smaller straw production. Results showed that the G effect on PUE was significant in year 1, but not in year 2. In the conditions of the moderate P availability (year 1), the variety Defes had the highest PUE and grain yield. Where P availability was lower (year 2), the highest PUE was reached by Karabiga; however, the difference with Defes was not significant. Data showed also that PUE was positively correlated with harvest index (HI) and phosphorus harvest index (PHI). In year 1, genotypic variation for PUE was mainly explained by phosphorus utilization efficiency; but not by phosphorus uptake efficiency. From this study, we can conclude that for rainfed conditions, the breeding strategy is to develop genotypes like Defes with high HI and improved PUE. © 2012 Copyright Taylor and Francis Group, LLC.

The aim of this work was to compare Cr(III) and Cr(VI) removal kinetics from water by Pistia stratiotes and Salvinia herzogii. The accumulation in plant tissues and the effects of both Cr forms on plant growth were also evaluated. Plants were exposed to 2 and 6 mg L−1 of Cr(III) or Cr(VI) during 30 days. At the end of the experiment, Cr(VI) removal percentages were significantly lower than those obtained for Cr(III) for both macrophytes. Cr(III) removal kinetics involved a fast and a slow component. The fast component was primarily responsible for Cr(III) removal while Cr(VI) removal kinetics involved only a slow process. Cr accumulated principally in the roots. In the Cr(VI) treatments a higher translocation from roots to aerial parts than in Cr(III) treatments was observed. Both macrophytes demonstrated a high ability to remove Cr(III) but not Cr(VI). Cr(III) inhibited the growth at the highest studied concentration of both macrophytes while Cr(VI) caused senescence. These results have important implications in the use of constructed wetlands for secondary industrial wastewater treatment. Common primary treatments of effluents containing Cr(VI) consists in its reduction to Cr(III). Cr(III) concentrations in these effluents are normally below the highest studied concentrations in this work. Fil: Maine, Maria Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Laboratorio de Química Analitica; Argentina Fil: Hadad, Hernán Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Laboratorio de Química Analitica; Argentina Fil: Sánchez, Gabriela Cristina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Laboratorio de Química Analitica; Argentina Fil: Caffaratti, Sandra Ester. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Laboratorio de Química Analitica; Argentina Fil: Pedro, María del Carmen. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Laboratorio de Química Analitica; Argentina

Background: Cancer is the leading cause of death in human disease and is a major public health problem around the world. Exosomes are a promising cancer biomarker and therapy target. Recent evidence demonstrate that tumor cells could inhibit natural killer (NK) cells’ immune surveillance function by releasing exosomes into tumor microenvironment. The intercelluar uptake of tumor cell-derived exosomes by NK cells is vital for using these exosomes in tumor diagnose and therapy. We aimed to investigate the efficiency of NK cell uptake of tumor exosomes. Methods: Exosomes derived from different tumor cells, RAW264.7 cells and NK cells were labeled by fluorescent dye and co-cultured with NK cells. The uptake rates of NK cells were observed by fluorescence microscope and analyzed by flow cytometry. Results: NK cells could take up more exosomes from themselves and cell lines originating from bone marrow. Epithelial cell lines can take up more exosomes from epithelial cells. There was no significant difference in uptake efficiency between Jurkat cells and RAW264.7 cells by NK cells, indicating that maybe the origin other than species affects the efficiency of recipient cell uptake of exosomes. Different tumor cells derived exosomes had different uptake efficiency by NK cells. Conclusion: There is certain pattern of NK cells uptake tumor exosomes, which provide important insights on how tumors affect NK cells and develop appropriate countermeasures. In addition, it can be also helpful to select and design proper exosomes as a drug carrier in future.