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Silver nanoparticles (AgNPs) are among the most produced nanomaterials in the world and are incorporated into several products due to their biocide and physicochemical properties. Since freshwater bodies are AgNPs main final sink, several consequences for biota are expected to occur. With the hypothesis that AgNPs can interact with environmental factors, we analyzed their ecotoxicity in combination with humic acids and algae. In addition to the specific AgNPs behavior in the media, we analyzed the mortality, growth, and phototactic behavior of Chydorus eurynotus (Cladocera) as response variables. While algae promoted Ag+ release, humic acids reduced it by adsorption, and their combination resulted in an intermediated Ag+ release. AgNPs affected C. eurynotus survival and growth, but algae and humic acids reduced AgNPs lethality, especially when combined. The humic acids mitigated AgNP effects in C. eurynotus growth, and both factors improved its phototactic behavior. It is essential to deepen the study of the isolated and combined influences of environmental factors on the ecotoxicity of nanoparticles to achieve accurate predictions under realistic exposure scenarios.
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This study analyzed total mercury (THg), and selenium (Se) in edible tissues of white shrimp (Litopenaeus vannamei), blue shrimp (L. stylirostris) and brown shrimp (F. californiensis), from three states of the Northwest of Mexico in September and October 2017. Concentrations of THg and Se in the muscle were between 0.026 and 0.829 and 0.126-1.741 µg/g dry weight (dw), respectively. Significant differences were observed among Hg concentration of Sonora and Nayarit and among Se concentration of Sinaloa and Nayarit. In addition, the health risk assessment (HQ) in the three species of shrimp was between 0.550 and 0.607. All Se:Hg molar ratios were > 1 and positive HBVSe values that showed that shrimp from Northwest of Mexico does not represent a risk to human health.
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Mercúrio , Penaeidae , Selênio , Poluentes Químicos da Água , Humanos , Animais , Mercúrio/análise , Selênio/toxicidade , Selênio/análise , México , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Medição de Risco , Monitoramento AmbientalRESUMO
The last eukaryotic common ancestor had two classes of introns that are still found in most eukaryotic lineages. Common U2-type and rare U12-type introns are spliced by the major and minor spliceosomes, respectively. Relatively few splicing factors have been shown to be specific to the minor spliceosome. We found that the maize (Zea mays) RNA binding motif protein 48 (RBM48) is a U12 splicing factor that functions to promote cell differentiation and repress cell proliferation. RBM48 is coselected with the U12 splicing factor, zinc finger CCCH-type, RNA binding motif, and Ser/Arg rich 2/Rough endosperm 3 (RGH3). Protein-protein interactions between RBM48, RGH3, and U2 Auxiliary Factor (U2AF) subunits suggest major and minor spliceosome factors required for intron recognition form complexes with RBM48. Human RBM48 interacts with armadillo repeat containing 7 (ARMC7). Maize RBM48 and ARMC7 have a conserved protein-protein interaction. These data predict that RBM48 is likely to function in U12 splicing throughout eukaryotes and that U12 splicing promotes endosperm cell differentiation in maize.
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Proteínas de Plantas/metabolismo , Splicing de RNA , RNA Nuclear Pequeno/metabolismo , Spliceossomos , Zea mays/genética , Diferenciação Celular , Endosperma/genética , Endosperma/fisiologia , Íntrons/genética , Fenótipo , Proteínas de Plantas/genética , RNA Nuclear Pequeno/genética , Motivos de Ligação ao RNA , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Zea mays/fisiologiaRESUMO
Cadmium (Cd2+) and copper (Cu2+) are considered immunotoxic metals and their presence in combination in the aquatic environment may cause effects on shrimp species as Litopenaeus vannamei. Thus, this research evaluates the combined effects of Cd2+ and Cu2+ on shrimp inoculated with Vibrio harveyi bacteria. The experiments were performed at 96-h of exposure to sublethal concentrations of both metals. No mortality was observed in organisms exposed to the sum of Criterion of Continuous Concentration (ΣCCC) in Cd + Cu mixture and those inoculated with V. harveyi. Higher clotting times were recorded in Cd + Cu + V. harveyi treatment at higher metal concentrations. No significant differences (P > 0.05) were recorded in hemocyanin content between shrimp exposed to metals and those experimentally infected. Significantly higher (P < 0.05) total hemocyte count (THC) was recorded at 96 h exposure in the ΣCCC and 10% treatments of Cd + Cu + V. harveyi experiment. Regarding Cd + Cu + V. harveyi bioassay, the highest phenoloxidase (PO) activity was recorded in shrimp inoculated with V. harveyi (0.326 ± 0.031 PO units/mg protein) at 96-h exposure. The lowest PO activity was observed in organisms exposed to Cd + Cu + V. harveyi. Regarding superoxide dismutase (SOD) activity, shrimp exposed to higher metal concentrations at 96 h showed the lowest hemolymph activity (6.03 ± 0.62 SOD units/mL). Protein decrease was observed in organisms exposed to metal mixture. The results showed that L. vannamei could be more susceptible to V. harveyi when exposed to Cd + Cu.
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Cádmio , Penaeidae , Animais , Cádmio/toxicidade , Cobre/toxicidade , Hemocianinas/farmacologia , Monofenol Mono-Oxigenase , Superóxido Dismutase/farmacologia , VibrioRESUMO
This paper discusses the minimization of the total annual operative cost for a planning period of 20 years composed by the annualized costs of the energy purchasing at the substation bus summed with the annualized investment costs in photovoltaic (PV) sources, including their maintenance costs in distribution networks based on their optimal siting and sizing. This problem is presented using a mixed-integer nonlinear programming model, which is resolved by applying a master-slave methodology. The master stage, consisting of a discrete-continuous version of the Vortex Search Algorithm (DCVSA), is responsible for providing the optimal locations and sizes for the PV sources-whereas the slave stage employs the Matricial Backward/Forward Power Flow Method, which is used to determine the fitness function value for each individual provided by the master stage. Numerical results in the IEEE 33- and 69-node systems with AC and DC topologies illustrate the efficiency of the proposed approach when compared to the discrete-continuous version of the Chu and Beasley genetic algorithm with the optimal location of three PV sources. All the numerical validations were carried out in the MATLAB programming environment.
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To more sustainably mitigate the impact of crop diseases on plant health and productivity, there is a need for broader spectrum, long-lasting resistance traits. Defense response (DR) genes, located throughout the genome, participate in cellular and system-wide defense mechanisms to stave off infection by diverse pathogens. This multigenic resistance avoids rapid evolution of a pathogen to overcome host resistance. DR genes reside within resistance-associated quantitative trait loci (QTL), and alleles of DR genes in resistant varieties are more active during pathogen attack relative to susceptible haplotypes. Differential expression of DR genes results from polymorphisms in their regulatory regions, that includes cis-regulatory elements such as transcription factor binding sites as well as features that influence epigenetic structural changes to modulate chromatin accessibility during infection. Many of these elements are found in clusters, known as cis-regulatory modules (CRMs), which are distributed throughout the host genome. Regulatory regions involved in plant-pathogen interactions may also contain pathogen effector binding elements that regulate DR gene expression, and that, when mutated, result in a change in the plants' response. We posit that CRMs and the multiple regulatory elements that comprise them are potential targets for marker-assisted breeding for broad-spectrum, durable disease resistance.
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Melhoramento Vegetal , Locos de Características Quantitativas , Resistência à Doença/genética , Haplótipos , Doenças das Plantas/genética , Plantas/genética , Locos de Características Quantitativas/genéticaRESUMO
Concentrations of Ag, Cr, Mn and Ni were measured in tissues of two whale sharks (Rhincodon typus) stranded in La Paz Bay (LAP) and Punta Bufeo (PB), Gulf of California, during 2017 and 2018. The concentration range of Ni (0.012-1.12 µg/g ww) and Cr (0.16-5.21) in the epidermis of both specimens was lower compared to the concentrations found in the epidermis of whale sharks from East Africa. The whale shark from LAP exhibited higher levels of Mn (4.45 µg/g ww), Ni (0.284 µg/g ww) and Cr (5.21 µg/g ww) in the muscle compared to another filter feeder shark, the megamouth, from Taiwan and from Brazil. The highest concentrations of Ag were found in the heart (3.70) of the individual from LAP and in the filtering pads (1.93) of the shark from PB. Chromium in all selected tissues and the Mn found in the skeletal muscle, testicles (0.50), liver (Right lobe, 1.28; Left lobe, 1.63) and gills (1.54) of both sharks exceeded the limit established by the FAO/WHO for fish products.
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Níquel , Tubarões , Animais , Epiderme , Manganês , PrataRESUMO
RNA splicing of U12-type introns functions in human cell differentiation, but it is not known whether this class of introns has a similar role in plants. The maize ROUGH ENDOSPERM3 (RGH3) protein is orthologous to the human splicing factor, ZRSR2. ZRSR2 mutations are associated with myelodysplastic syndrome (MDS) and cause U12 splicing defects. Maize rgh3 mutants have aberrant endosperm cell differentiation and proliferation. We found that most U12-type introns are retained or misspliced in rgh3 Genes affected in rgh3 and ZRSR2 mutants identify cell cycle and protein glycosylation as common pathways disrupted. Transcripts with retained U12-type introns can be found in polysomes, suggesting that splicing efficiency can alter protein isoforms. The rgh3 mutant protein disrupts colocalization with a known ZRSR2-interacting protein, U2AF2. These results indicate conserved function for RGH3/ZRSR2 in U12 splicing and a deeply conserved role for the minor spliceosome to promote cell differentiation from stem cells to terminal fates.
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Genes de Plantas , Splicing de RNA , RNA Nuclear Pequeno , Zea mays/genética , Processamento Alternativo , Sequência de Aminoácidos , Sequência Conservada , Endosperma/genética , Células Eucarióticas/metabolismo , Regulação da Expressão Gênica de Plantas , Humanos , Íntrons , Mutação , Motivos de Nucleotídeos , Fosforilação , Matrizes de Pontuação de Posição Específica , Transporte Proteico , Isoformas de RNA , Sítios de Splice de RNA , Fator de Processamento U2AF/genética , Fator de Processamento U2AF/metabolismo , Zea mays/metabolismoRESUMO
INTRODUCTION: the secretion of antigens from the diet into breast milk has been extensively documented. The transfer of gliadin could be critical for the development of an immune response. OBJECTIVES: to investigate the presence of immunogenic gluten peptides in the feces of infants fed with different diets. MATERIAL AND METHODS: a blind, prospective, controlled, collaborative study was performed in three hospitals, between September 2016 and January 2017. The study protocol was approved by the Ethics Committee of the hospitals in Seville prior to starting the study. RESULTS: the cohort was divided into three groups of 30 infants: an experimental group (average age 9.2 ± 2.8 weeks) with exclusive breastfeeding, a control group 1 (average age 10.3 ± 3.3 weeks) exclusively fed with onset formula and a control group 2 (average age 56 ± 3.7 weeks) with infants that consumed gluten on a regular basis. The peptide 33-mer of gliadin was negative in all feces samples from both the experimental and control group 1. With regard to control group 2, the peptide 33-mer of gliadin was negative in 23% of cases (seven children). There was no difference in the amount of gluten ingested by these children compared to those who excreted the 33-mer peptide. CONCLUSIONS: the failure to detect gluten in the feces of infants that were exclusively breastfed indicates that it is probably below the limits of detection. Healthy children who consume gluten may not excrete it in feces.
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Fezes/química , Gliadina/análise , Glutens/análise , Leite Humano/química , Aleitamento Materno , Estudos de Casos e Controles , Feminino , Glutens/administração & dosagem , Glutens/imunologia , Humanos , Lactente , Fórmulas Infantis , Masculino , Leite Humano/imunologia , Estudos Prospectivos , Método Simples-Cego , EspanhaRESUMO
Three-dimensional transthoracic echocardiography (3DTTE) may have a role in predicting final left ventricular volumes and clinical response after the surgical ventricular reconstruction (SVR) of left ventricular aneurysms and pseudoaneurysms. Left ventricle final volumes can be calculated through "virtual aneurysmectomy." We present a patient with a huge ventricular dilation combined with myocardial dissection, localized wall rupture, and aneurysm of the left ventricular apex after acute myocardial infarction in which accurate predictions from 3DTTE suggest potential clinical value.
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Procedimentos Cirúrgicos Cardíacos/métodos , Volume Cardíaco/fisiologia , Ecocardiografia Doppler em Cores/métodos , Ecocardiografia Tridimensional/métodos , Aneurisma Cardíaco/cirurgia , Ventrículos do Coração/diagnóstico por imagem , Procedimentos de Cirurgia Plástica/métodos , Adulto , Seguimentos , Aneurisma Cardíaco/diagnóstico , Aneurisma Cardíaco/fisiopatologia , Humanos , Masculino , Período Pós-OperatórioRESUMO
The impact of nanomaterials in the environment and human health is a cause of big concern and even though intensive studies are currently being carried out, there is still a lot to elucidate. The development of validated methods for the characterization and quantification of nanomaterials and their impact on the environment should be encouraged to achieve a proper, safe, and sustainable use of nanoparticles (NPs). Recently, CE emerged as a well-adapted technique for the analysis of environmental samples. This review presents the application of NPs together with CE systems for environmental pollutants analysis, as well as the application of CE techniques for the analysis of various types of NPs.
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Poluentes Ambientais/análise , Nanopartículas/análise , Nanoestruturas/análise , Eletroforese Capilar/métodosRESUMO
INTRODUCTION: Capsule Endoscopy (CE) in children has limitations based mainly on age. The objective of this consensus was reviewing the scientific evidence. MATERIAL AND METHODS: Some experts from the Spanish Society of Gastroenterology (SEPD) and Spanish Society for Pediatric Gastroenterology, Hepatology, and Nutrition (SEGHNP) were invited to answer different issues about CE in children. These sections were: a) Indications, contraindications and limitations; b) efficacy of CE in different clinical scenarios; c) CE performance; d) CE-related complications; e) Patency Capsule; and f) colon capsule endoscopy. They reviewed relevant questions on each topic. RESULTS: The main indication is Crohn's disease (CD). There is no contraindication for the age and in the event that the patient not to swallow it, it should be administered under deep sedation with endoscopy and specific device. The CE is useful in CD, for the management of OGIB in children and in Peutz-Jeghers syndrome (in this indication has the most effectiveness). The main complication is retention, which should be specially taken into account in cases of CD already diagnosed with malnutrition. A preparation regimen based on a low volume of polyethylene glycol (PEG) the day before plus simethicone on the same day is the best one in terms of cleanliness although does not improve the results of the CE procedure. CONCLUSIONS: CE is safe and useful in children. Indications are similar to those of adults, the main one is CD to establish both a diagnosis and disease extension. Moreover, only few limitations are detected in children.
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Endoscopia por Cápsula , Doença de Crohn/diagnóstico por imagem , Hemorragia Gastrointestinal/diagnóstico por imagem , Intestino Delgado/diagnóstico por imagem , Síndrome de Peutz-Jeghers/diagnóstico por imagem , Adolescente , Endoscopia por Cápsula/efeitos adversos , Endoscopia por Cápsula/métodos , Criança , Colo/diagnóstico por imagem , Contraindicações , Hemorragia Gastrointestinal/etiologia , HumanosRESUMO
Endosperm and embryo development are coordinated via epigenetic regulation and signaling between these tissues. In maize (Zea mays), the endosperm-embryo signals are not known, but endosperm cellularization is a key event for embryos to form shoots and roots. We screened seed mutants for nonautonomous functions in endosperm and embryo development with genetically nonconcordant seeds and identified the recessive mutant rough endosperm3 (rgh3). The wild-type Rgh3 allele is required in the endosperm for embryos to develop and has an autonomous role in embryo and seedling development. Endosperm cell differentiation is defective in rgh3. Results from endosperm cell culture indicate that rgh3 mutants remain in a proliferative state through mid-seed development. Rgh3 encodes the maize U2AF(35) Related Protein (URP), an RNA splicing factor involved in both U2 and U12 splicing. The Rgh3 allele produces at least 19 alternative splice variants with only one isoform encoding a full-length ortholog to URP. The full-length RGH3α isoform localizes to the nucleolus and displays a speckled pattern within the nucleoplasm, and RGH3α colocalizes with U2AF(65). A survey of alternatively spliced transcripts found that, in the rgh3 mutant, a fraction of noncanonical splicing events are altered. Our findings suggest that differentiation of maize endosperm cell types is necessary for embryos to develop. The molecular cloning of Rgh3 suggests that alternative RNA splicing is needed for cell differentiation, development, and plant viability.
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Processamento Alternativo , Diferenciação Celular , Endosperma/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Zea mays/embriologia , Zea mays/genética , Agrobacterium tumefaciens/genética , Agrobacterium tumefaciens/metabolismo , Alelos , Sequência de Aminoácidos , Biomarcadores/metabolismo , Técnicas de Cultura de Células , Nucléolo Celular/genética , Nucléolo Celular/metabolismo , Clonagem Molecular , Cruzamentos Genéticos , Endosperma/embriologia , Endosperma/genética , Endosperma/metabolismo , Genes de Plantas , Teste de Complementação Genética , Dados de Sequência Molecular , Fenótipo , Células Vegetais/metabolismo , Proteínas de Plantas/genética , Polinização , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Alinhamento de Sequência , Translocação Genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismoRESUMO
The human body possesses a remarkable ability to heal itself from injuries [...].
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The skin is the largest organ of the body, and it acts as a protective barrier against external factors. Chronic wounds affect millions of people worldwide and are associated with significant morbidity and reduced quality of life. One of the main factors involved in delayed wound healing is oxidative injury, which is triggered by the overproduction of reactive oxygen species. Oxidative stress has been implicated in the pathogenesis of chronic wounds, where it is known to impair wound healing by causing damage to cellular components, delaying the inflammatory phase of healing, and inhibiting the formation of new blood vessels. Thereby, the treatment of chronic wounds requires a multidisciplinary approach that addresses the underlying causes of the wound, provides optimal wound care, and promotes wound healing. Among the promising approaches to taking care of chronic wounds, antioxidants are gaining interest since they offer multiple benefits related to skin health. Therefore, in this review, we will highlight the latest advances in the use of natural polymers with antioxidants to generate tissue regeneration microenvironments for skin wound healing.
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The present study analyzed the content of total mercury (THg) and selenium (Se) in the muscle of shrimp collected from local markets in the 11 Pacific coastal states of Mexico. Methylmercury (MeHg) concentration, Se:Hg ratio, health benefits value from selenium consumption (HBVSe) and the permissible weekly consumption were estimated to assess the health risk to consumers. All THg and Se concentrations were below the maximum permissible limits. All hazard quotient (HQ) values were <1, however in Hermosillo, Culiacán and Guadalajara, the Se:Hg ratio and HBVSe were <1 and negative, due to the low concentrations of Se. As a general conclusion, there is no risk nor benefit from the consumption of shrimp from the Pacific coast of Mexico due to its Hg and Se content.
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Mercúrio , Compostos de Metilmercúrio , Selênio , Poluentes Químicos da Água , Animais , Mercúrio/análise , Selênio/análise , México , Poluentes Químicos da Água/análise , CrustáceosRESUMO
The synthesis of monodispersed magnetic silica nanoparticles (MSN) is described using a water-in-oil reverse microemulsion system that does not require the use of co-surfactants. Sodium silicate, Tween 20 as a neutral surfactant and 1-butanol as the organic phase were used. There are several advantages of the proposed method including a saturation magnetization value of 10 emu/g for the particles obtained, uniformity of size and that they are easily functionalized to bind urease covalently. Moreover, the intra-day, inter-day and long-term stability results confirm that the procedure was successful and the enzyme-linked MSNs were stable over repeated uses and storage retaining more than 75% activity after 4 months.
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Emulsões , Enzimas Imobilizadas/metabolismo , Magnetismo , Nanopartículas , Dióxido de Silício , Urease/metabolismo , Biotecnologia/métodos , Estabilidade Enzimática , Enzimas Imobilizadas/química , Urease/químicaRESUMO
Cannabis sativa L. has been used as medicine for thousands of years. Since the early identification of tetrahydrocannabinol (THC) in 1960, pharmacological activities were attributed to a group of unique structures named cannabinoids. For decades, research and development were applied to determine different cannabinoids and their medicinal properties. Nowadays there is evidence that the therapeutic benefits of the plant are based on the synergy of cannabinoids and other secondary metabolites such as terpenes and flavonoids. Differences between the medical performance of isolated compounds like cannabidiol (CBD) or THC and full-spectrum plant extracts are notable. Indeed, the superiority of the last one is provoked by the synergy between various different compounds. This improved medicinal effect is called the entourage effect. Chromatography has become the method of choice for the determination of cannabinoids, terpenes, and flavonoids, so it represents an excellent tool for a proper characterization of the plant and plant derived products. The objective of characterization relies not only in analyzing the fingerprint of cannabis, but also to identify different chemotypes for medical purposes. To understand the contributions of each natural product to this "entourage effect", this review presents an in-depth analysis of the utilization of High-performance liquid chromatography (HPLC), Gas chromatography (GC) and other methods for the analysis of phytocomponents of Cannabis sativa L. In this sense, a representative number of examples and advances made in the field together with limitations and future needs are provided. It can be concluded that standardized protocols and quality control policies and procedures are necessary for the comprehensive analysis of cannabis extracts and derivatives.
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Canabidiol , Canabinoides , Cannabis , Humanos , Cannabis/química , Cannabis/metabolismo , Metabolismo Secundário , Canabinoides/análise , Canabinoides/química , Canabinoides/farmacologia , Canabidiol/farmacologia , Terpenos/análise , Flavonoides/metabolismo , Cromatografia Gasosa , Dronabinol/análise , Dronabinol/metabolismo , Dronabinol/farmacologiaRESUMO
The green synthesis of nanomaterials is nowadays gaining great attention owing to several beneficial aspects in terms of the low toxicity of reagents and by-products, low damage to the health and the environment, sustainability of energy savings and rational use of natural resources. The intrinsic complexity offered by the biological sources (plants, microorganisms, animal products) and the conditions applied in the synthetic procedures forms various nanomaterials with different sizes, morphologies and surface properties that strongly determine their functionality and applications. A deep understanding of the role of biological components, the mechanism of nanostructure formation and growth, and the effects of green synthesis conditions is of paramount importance to achieving the desired nanomaterial for the required application. In this context, this review aims to provide an overview of the structural and functional complexity of nanomaterials achieved by using green synthesis procedures, with a special focus on the role of biological sources and parameters in controlling the complexity and benefit of nanomaterial applications.
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Nanoestruturas , Animais , Nanoestruturas/química , Propriedades de SuperfícieRESUMO
Silver nanoparticles (AgNPs) are applied in diverse industries due to their biocide and physicochemical properties; therefore, they can be released into aquatic systems, interact with environmental factors, and ultimately exert adverse effects on the biota. We analyzed AgNPs effects on Ceriodaphnia reticulata (Cladocera) through mortality and life-history traits, considering the influence of food (Tetradesmus obliquus, Chlorophyceae) presence and concentration. C. reticulata was exposed to AgNPs in acute (absence and two algae concentrations plus five AgNPs treatments) and chronic assays (two algae concentrations plus three AgNPs treatments). AgNPs did not affect algae flocculation but increased Ag+ release, being these ions less toxic than AgNPs (as proved by the exposure to AgNO3). A reduction in AgNPs acute toxicity was observed when algae concentration increased. Acute AgNP exposure decreased C. reticulata body size and heart rate. The chronic AgNP exposure reduced C. reticulata molt number, growth, heart rate, and neonate size:number ratio, being these effects mitigated at the highest algae concentration. Increases in relative size and number of neonates were observed in AgNP treatments suggesting energy trade off. The increased Ag+ release with food presence suggests that the AgNP-algae interaction might be responsible of the decreased toxicity. Although algae reduced AgNP toxicity, they still exerted adverse effects on C. reticulata below predicted environmental concentrations. Since algae presence reduces AgNP effects but increases Ag+ release, studies should be continued to provide evidence on their toxicity to other organisms.