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1.
Ecotoxicol Environ Saf ; 170: 538-547, 2019 Apr 15.
Article in English | MEDLINE | ID: mdl-30572249

ABSTRACT

Chemical environmental pollution is currently one of the most concerning environmental problem on a global scale, due to the high risks posed to ecological systems and human health. Risk assessment methodologies are valuable tools for preventive management and the mitigation of human health risks. However, the application of these methodological tools involves several steps and the knowledge of many variables, which can hinder its correct implementation. The main objective of this work was the development of the computational code for human health risk assessment: HHRISK (Human Health Risk). This code allows for an agile and accurate risk assessment based on the methodology established by the U.S. Environmental Protection Agency (U.S. EPA). Different from other published methods, the HHRISK code includes a new spatiotemporal matrix for the analysis of the aggregated risk (for multiple exposure pathways) and the cumulative (for exposure to multiple chemicals). HHRISK was applied to two case studies published dealing with the assessment of risk to human health through exposure to toxic metals, obtaining satisfactory results. The concordance between the average results obtained with the HHRISK and those reported by the authors confirm the validity of the implemented model. The inclusion of a greater spatiotemporal detail of the risks allowed to carry out a more accurate analysis and to propose new subsidies for a more efficient risk mitigation management by affected place and period of time.


Subject(s)
Environmental Exposure/analysis , Environmental Monitoring/methods , Environmental Pollutants , Risk Assessment/methods , Environmental Pollutants/chemistry , Environmental Pollutants/toxicity , Humans , United States , United States Environmental Protection Agency
2.
Int J Syst Evol Microbiol ; 68(5): 1608-1615, 2018 May.
Article in English | MEDLINE | ID: mdl-29557767

ABSTRACT

Three morphologically similar thermo-acidophilic strains, USBA-GBX-501, USBA-GBX-502 and USBA-GBX-503T, were isolated from acidic thermal springs at the National Natural Park Los Nevados (Colombia). All isolates were spore-forming, Gram-stain-positive and motile, growing aerobically at 25-55 °C (optimum ~45 °C) and at pH 1.5-4.5 (optimum pH ~3.0). Phylogenetic analysis of the 16S rRNA gene sequences of these isolates showed an almost identical sequence (99.0 % similarity) and they formed a robust cluster with the closest relative Alicyclobacillus tolerans DSM 16297T with a sequence similarity of 99.0 %. Average similarity to other species of the genus Alicyclobacillus was 93.0 % and average similarity to species of the genus Effusibacillus was 90 %. In addition, the level of DNA-DNA hybridization between strain USBA-GBX-503T and Alicyclobacillus tolerans DSM 16297T was 31.7 %. The genomic DNA G+C content of strain USBA-GBX-503T was 44.6 mol%. The only menaquinone was MK-7 (100.0 %). No ω-alicyclic fatty acids were detected in strain USBA-GBX-503T, and the major cellular fatty acids were C18 : 1ω7c, anteiso-C17 : 0 and iso-C17 : 0. Based on phenotypic and chemotaxonomic characteristics, phylogenetic analysis and DNA-DNA relatedness values, along with low levels of identity at the whole genome level (ANIb and ANIm values of <67.0 and <91.0 %, respectively), it can be concluded that strain USBA-GBX-503T represents a novel species of the genus Alicyclobacillus, for which the name Alicyclobacillus montanus sp. nov. is proposed. The type strain is USBA-GBX-503T (=CMPUJ UGB U503T=CBMAI1927T).


Subject(s)
Alicyclobacillus/classification , Hot Springs/microbiology , Phylogeny , Alicyclobacillus/genetics , Alicyclobacillus/isolation & purification , Bacterial Typing Techniques , Base Composition , Colombia , DNA, Bacterial/genetics , Fatty Acids/chemistry , Nucleic Acid Hybridization , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Vitamin K 2/analogs & derivatives , Vitamin K 2/chemistry
3.
Persoonia ; 41: 39-55, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30728598

ABSTRACT

Over the past few years, symptoms akin to late blight disease have been reported on a variety of crop plants in South America. Despite the economic importance of these crops, the causal agents of the diseases belonging to the genus Phytophthora have not been completely characterized. In this study, a new Phytophthora species was described in Colombia from tree tomato (Solanum betaceum), a semi-domesticated fruit grown in northern South America. Comprehensive phylogenetic, morphological, population genetic analyses, and infection assays to characterize this new species, were conducted. All data support the description of the new species, Phytophthora betacei sp. nov. Phylogenetic analyses suggest that this new species belongs to clade 1c of the genus Phytophthora and is a close relative of the potato late blight pathogen, P. infestans. Furthermore, it appeared as the sister group of the P. andina strains collected from wild Solanaceae (clonal lineage EC-2). Analyses of morphological and physiological characters as well as host specificity showed high support for the differentiation of these species. Based on these results, a complete description of the new species is provided and the species boundaries within Phytophthora clade 1c in northern South America are discussed.

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