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1.
Persoonia ; 52: 44-93, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39161630

RESUMO

Oceanic islands have been recognized as natural laboratories in which to study a great variety of evolutionary processes. One such process is evolutionary radiations, the diversification of a single ancestor into a number of species that inhabit different environments and differ in the traits that allow them to exploit those environments. The factors that drive evolutionary radiations have been studied for decades in charismatic organisms such as birds or lizards, but are lacking in lichen-forming fungi, despite recent reports of some lineages showing diversification patterns congruent with radiation. Here we propose the Ramalina decipiens group as a model system in which to carry out such studies. This group is currently thought to be comprised of five saxicolous species, all of them endemic to the Macaronesian region (the Azores, Madeira, Selvagens, Canary and Cape Verde islands). Three species are single-island endemics (a rare geographic distribution pattern in lichens), whereas two are widespread and show extreme morphological variation. The latter are suspected to harbor unrecognized species-level lineages. In order to use the Ramalina decipiens group as a model system it is necessary to resolve the group's phylogeny and to clarify its species boundaries. In this study we attempt to do so following an integrative taxonomy approach. We constructed a phylogenetic tree based on six molecular markers, four of which are newly developed and generated competing species hypotheses based on molecular (species discovery strategies based on both single locus and multilocus datasets) and phenotypic data (unsupervised clustering algorithms based on morphology, secondary chemistry and geographic origin). We found that taxonomic diversity in the Ramalina decipiens group has been highly underestimated in previous studies. In consequence, we describe six new species, most of them single-island endemics and provide a key to the group. Phylogenetic relationships among species have been reconstructed with almost full support which, coupled with the endemic character of the group, makes it an excellent system for the study of island radiations in lichen-forming fungi. Citation: Blázquez M, Pérez-Vargas I, Garrido-Benavent I, et al. 2024. Endless forms most frustrating: disentangling species boundaries in the Ramalina decipiens group (Lecanoromycetes, Ascomycota), with the description of six new species and a key to the group. Persoonia 52: 44-93. https://doi.org/10.3767/persoonia.2024.52.03 .

2.
J Biotechnol ; 360: 192-197, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36343756

RESUMO

Ionic liquids (ILs) are widely applied in many bioprocesses involving microorganisms due to their unique properties. In this work, the toxicity of imidazolium and pyrrolidinium ionic liquids towards E. coli., a bacterium for which there are limited toxicity data in the literature, was determined. For its simplicity, the nephelometry method was used to estimate ionic liquid toxicity values. The influence of the cation and the alkyl chain length of the cation and anion was analysed. Pyrrolidinium cations were seen to be less toxic than imidazolium cations, while an increase in the alkyl chain length of both pyrrolidinium and imidazolium cations increased the toxicity. Among the anions studied, dimethylphosphate ([Me2PO4]) was the less toxic, while the EC50 for the ionic liquid 1-butyl-3-methylpyrrolidinium dimethylphosphate ([C1C4Pyr][Me2PO4]) was close to 200 mM. Furthermore, a dicationic ionic liquid based on imidazolium and pyrrolidinium cations was synthetized and its toxicity toward E. coli was analysed, maintaining a growth rate of 100 % in the range 0-0.76 mM. The methodology used in this work allows to easily find the less toxic ionic liquids that are biocompatible with E. coli to be used in new bioprocesses.


Assuntos
Líquidos Iônicos , Líquidos Iônicos/toxicidade , Escherichia coli , Cátions
4.
Sci Total Environ ; 770: 144557, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33508664

RESUMO

Soils can influence climate by sequestering or emitting greenhouse gases (GHG) such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). We are far from understanding the direct influence of cryptogamic covers on soil GHG fluxes, particularly in areas free of potential anthropogenic confounding factors. We assessed the role of well-developed cryptogamic covers in soil attributes, as well as in the in-situ exchange of GHG between Antarctic soils and the atmosphere during the austral summer. We found lower values of soil organic matter, total organic carbon, and total nitrogen in bare areas than in soils covered by mosses and, particularly, lichens. These differences, together with concomitant decreases and increases in soil temperature and moisture, respectively, resulted in increases in in-situ CO2 emission (i.e. ecosystem respiration) and decreases in CH4 uptake but no significant changes in N2O fluxes. We found consistent linear positive and negative relationships between soil attributes (i.e. soil organic matter, total organic carbon and total nitrogen) and CO2 emissions and CH4 uptake, respectively, and polynomial relationships between these soil attributes and net N2O fluxes. Our results indicate that any increase in the area occupied by cryptogams in terrestrial Antarctic ecosystems (due to increased growing season and increasingly warming conditions) will likely result in parallel increases in soil fertility as well as in an enhanced capacity to emit CO2 and a decreased capacity to uptake CH4. Such changes, unless offset by parallel C uptake processes, would represent a paradigmatic example of a positive climate change feedback. Further, we show that the fate of these terrestrial ecosystems under future climate scenarios, as well as their capacity to exchange GHG with the atmosphere might depend on the relative ability of different aboveground cryptogams to thrive under the new conditions.


Assuntos
Gases de Efeito Estufa , Regiões Antárticas , Dióxido de Carbono/análise , Ecossistema , Gases de Efeito Estufa/análise , Metano/análise , Óxido Nitroso/análise , Solo
5.
Environ Technol ; 40(18): 2425-2435, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29455622

RESUMO

Microbial fuel cells (MFCs) are a promising technology that generates electricity from several biodegradable substrates and wastes. The main drawback of these devices is the need of using a catalyst for the oxygen reduction reaction at the cathode, which makes the process relatively expensive. In this work, two low cost materials are tested as catalysts in MFCs. A novel iron complex based on the ligand n-phenyledenparaethoxy aniline has been synthesized and its performance as catalyst in single chamber MFCs containing ionic liquids has been compared with a commercial inorganic material such as Raney nickel. The results show that both materials are suitable for bioenergy production and wastewater treatment in the systems. Raney nickel cathodes allow MFCs to reach a maximum power output of 160 mW.m-3 anode, while the iron complex offers lower values. Regarding the wastewater treatment capacity, MFCs working with Raney nickel-based cathodes reach higher values of chemical oxygen demand removal (76%) compared with the performance displayed by the cathodes based on Fe-complex (56%).


Assuntos
Fontes de Energia Bioelétrica , Catálise , Eletricidade , Eletrodos , Águas Residuárias
6.
Sci Total Environ ; 634: 116-126, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29627534

RESUMO

The present study analysed potential adverse effects of discontinuous sources of contamination, namely the discharge of a combined sewer overflow (CSO) and of runoff in an urban area, the Bay of Santander (North Iberian Peninsula). Water samples and caged mussels were used to analyse concentrations of contaminants and biological responses. Mussels (Mytilus galloprovincialis) were transplanted to a marina receiving runoff from a petrol station and to a CSO discharge site. Samples were collected in synchrony with heavy rains along 62days. Lysosomal membrane stability (LMS) and acyl-CoA oxidase (AOX) activity were measured as core biomarkers and were analysed at all sampling times. Histopathology of digestive gland and gonads, transcription levels of vitellogenin gene, volume density of black silver deposits and micronuclei formation were measured at initial and final stages of the transplant. Chemical analyses of metals, polycyclic aromatic hydrocarbons (PAHs) and endocrine disruptors were performed in water samples and mussel flesh. Mussels accumulated low concentrations of contaminants, which is in accordance with results obtained from exposure biomarkers. AOX activity decreased in all transplanted mussels after the first heavy rain, but this change seems to be related to the seasonal pattern of the enzyme activity. Mussels located close to the CSO discharge site showed a reduction in LMS after the first rain event, when compared to mussels before the transplant and to mussels from the reference location. However, this was attributable to natural environmental changes rather than to pollution. Values of the rest of analysed biomarkers were below threshold values reported for the study area.


Assuntos
Monitoramento Ambiental/métodos , Mytilus/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Biomarcadores/metabolismo , Disruptores Endócrinos/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Vitelogeninas/metabolismo
7.
Int J Phytoremediation ; 20(13): 1354-1361, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30666892

RESUMO

The remediation of contaminated dredged sediments is necessary to eliminate the risk towards human beings or the environment when there is disposal on land. A greenhouse experiment was carried out to evaluate the chemically assisted phytoextraction to clean up dredged sediment contaminated with Cr, Cu, Pb, and Zn. The ability of castor bean and chicory to absorb, translocate, and accumulate metals from sediment to root and shoot was evaluated by applying EDTA (5 mM), NTA (5 mM), and citric acid (60 mM) to sediment, before the harvest. Citric acid 60 mM was the most effective treatment in increasing Cr, Cu, and Pb in castor bean and chicory shoot. Chicory could accumulate 1730 mg Cr kg-1 in shoot, and had greater values than one for the bioaccumulation and translocation factors when citric acid was added to the sediment. But, the Cr percentages removed per harvest of chicory were 0.05% and were lower for Cu, Pb, and Zn due to low biomass obtained. Citric acid-assisted phytoextraction with chicory can be a promising short time solution to reduce Cr concentration in sediment and reach the Cr level guide for industrial land use only if suitable agronomic practices could be implemented to increase crop yield.


Assuntos
Cichorium intybus , Metais Pesados/análise , Ricinus communis , Poluentes do Solo/análise , Biodegradação Ambiental , Ácido Cítrico , Ácido Edético , Humanos , Ricinus
8.
Rev. chil. endocrinol. diabetes ; 10(4): 131-136, oct. 2017. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-998986

RESUMO

OBJECTIVE: To study the efficacy and safety of degludec insulin in Type 1 diabetic patients. PATIENTS AND METHOD: In a prospective study, 230 type 1 diabetics patients, average aged 34 years age and 14 years of diagnosis of diabetes and treated with two doses of insulin glargine U-100, were changed to degludec. Patients had glycosylated hemoglobins (HbA1c) greater than 10 percent. Results were recorded at 3 and 6 months with parameters clinical, biochemical, insulin requirements per kilogram of weight (U/kg/wt) and hypoglycemia. Capillary glycemia was evaluated three times a day and the dose of insulin degludec every two weeks. The statistical analysis used was average and rank, standard deviation, normal Swilk test, categorical Chi2 and continuous ANOVA or Kwallis, and p < 0.05. A psychological survey was conducted to evaluate satisfaction with the new treatment. RESULTS: Fasting blood glucose decreased from 253 (range 243-270) at 180 mg/dl (172-240) at 3 months and at 156 (137-180) at 6 months after the change insulin (p < 0.05). HbA1c, initially 10.6 percent (10.4-12.2) decreased to 8.7 percent (9.3-10.1) and 8.3 percent (8.7-9.7) at 3 and 6 months, respectively (p < 0.05). There was a decrease in basal insulin requirements from 0.7 to 0.4 U/kg/60 percent reduction in hypoglycaemia; both mild and moderate and severe. Isolated nocturnal hypoglycaemias were recorded in only 4 patients in this group. CONCLUSION: Six months of treatment with degludec insulin reduces fasting blood glucose, glycosylated hemoglobin and hypoglycemia, both mild and moderate severe and nocturnal, which makes this new ultra-long acting basal insulin a safe and effective tool for the management of type 1 diabetics patients


Assuntos
Humanos , Masculino , Adolescente , Adulto , Insulina de Ação Prolongada/uso terapêutico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Fatores de Tempo , Glicemia/efeitos dos fármacos , Inquéritos e Questionários , Seguimentos , Satisfação do Paciente , Insulina de Ação Prolongada/administração & dosagem , Insulina de Ação Prolongada/efeitos adversos , Insulina Glargina/administração & dosagem , Insulina Glargina/efeitos adversos , Hipoglicemia/induzido quimicamente
9.
J Hazard Mater ; 321: 484-499, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-27669390

RESUMO

Volatile organic compounds (VOCs) comprise a wide variety of carbon-based materials which are volatile at relatively low temperatures. Most of VOCs pose a hazard to both human health and the environment. For this reason, in the last years, big efforts have been made to develop efficient techniques for the recovery of VOCs produced from industry. The use of ionic liquids (ILs) is among the most promising separation technologies in this field. This article offers a critical overview on the use of ionic liquids for the separation of VOCs both in bulk and in immobilized form. It covers the most relevant works within this field and provides a global outlook on the limitations and future prospects of this technology. The extraction processes of VOCs by using different IL-based assemblies are described in detail and compared with conventional methods This review also underlines the advantages and limitations posed by ionic liquids according to the nature of the cation and the anions present in their structure and the stability of the membrane configurations in which ILs are used as liquid phase.

10.
Mar Environ Res ; 121: 49-63, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27017466

RESUMO

Data obtained in a pollution survey performed in estuarine areas were integrated using multivariate statistics. The sites selected for the study were areas affected by treated and untreated urban discharges, harbours or industrial activities as well as reference sites. Mussels were transplanted to each site and after different times of exposure, samples of water, sediments and mussels were collected. Biomarkers were analysed on mussels after 3 and 21 days of transplant whereas concentrations of contaminants were measured in water, sediments and mussels after 21 days of transplant. The structure of macroinvertebrate benthic communities was studied in sediment samples. Studied variables were organised into 5 datasets, each one constituting a line of evidence (LOE): contaminants in water, contaminants in sediments, contaminants accumulated by transplanted mussels, biomarkers in transplanted mussels and changes in the structure of macroinvertebrate benthic communities of each sampling site. Principal Component Analysis (PCA) identified the variables of each LOE best explaining variability among sites. In order to know how LOEs relate to each other, Pearson's correlations were performed. Contaminants in sediments were not correlated with the rest of LOEs. Contaminants in water were significantly correlated with contaminants and biomarkers in mussels and with structure of macroinvertebrate benthic communities. Similarly, significant correlations were found between contaminants and biomarkers in mussels and between biomarkers in mussels and structure of macroinvertebrate benthic communities. In conclusion, biomarker responses give relevant information on pollution in estuarine areas and provide a link between chemical and ecological statuses of water bodies in the context of the Water Framework Directive.


Assuntos
Bivalves/fisiologia , Ecossistema , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Animais , Estuários , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos
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