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1.
PLoS One ; 18(12): e0295534, 2023.
Article in English | MEDLINE | ID: mdl-38096159

ABSTRACT

The study aims to understand the dispersal patterns of non-indigenous Tubastraea spp. (Sun Coral) larvae in the Brazil Current (BC), specifically in the Cape Frio recurrent cyclonic eddy (CFE) scenario. For this, the Regional Ocean Model System was used to simulate the hydrodynamic fields in a high-resolution nested grid, where a model of lagrangian floats, in a good approximation of the larvae properties and considering massive planulation events, was coupled with surface larval release from the Campos Basin area. The simulation was representative of mesoscale features compared to similar studies, ARGO vertical profiles and a py-eddy-track algorithm was used to obtain eddy variables, such as radius, rotational and translational velocities. These parameters are fundamental to access when an eddy tends to trap or not the water, heat and plankton in its interior. CFE turned out to be highly nonlinear, with a strong tendency to trap larvae in its core, acting as a dispersal constrictor when compared with the organisms in the axis of the higher speed of BC. A strong negative correlation (-0.75) was found between the days that larvae were inside the eddy and their distance from the origin. None of the 48,000 larvae released during simulated experiment a 16-day spawning event reached the coast. There are two different patterns for the dispersal, one along the shelf break and another, with higher larval density, off from the 1000 m isobath. The CFE's presence allows larvae to remain in the same region for longer periods, although in offshore areas. Therefore, as there is considerable availability of fixed substrates on oil rig structures, larvae could settle on them resulting in a possible inter-platforms connectivity between populations of Tubastraea spp. Also, regions in the CFE that present downward vertical velocities (downwelling), may move young larvae to depths of about 60 m suggesting that subsurface colonizations are possible due to specific dynamics of propagating cyclonic eddies. So, identifying the main factors that affect the dispersion of propagules is essential to subsidize management policies for controlling bioinvasion associated with exploitation of hydrocarbon resources in offshore areas.


Subject(s)
Anthozoa , Physiological Phenomena , Animals , Larva , Brazil , Computer Simulation
2.
Biomolecules ; 12(6)2022 06 07.
Article in English | MEDLINE | ID: mdl-35740921

ABSTRACT

Plastics are a group of synthetic materials made of organic polymers and some additives with special characteristics. Plastics have become part of our daily life due to their many applications and uses. However, inappropriately managed plastic waste has raised concern regarding their ecotoxicological and human health risks in the long term. Due to the non-biodegradable nature of plastics, their waste may take several thousands of years to partially degrade in natural environments. Plastic fragments/particles can be very minute in size and are mistaken easily for prey or food by aquatic organisms (e.g., invertebrates, fishes). The surface properties of plastic particles, including large surface area, functional groups, surface topography, point zero charge, influence the sorption of various contaminants, including heavy metals, oil spills, PAHs, PCBs and DDT. Despite the fact that the number of studies on the biological effects of plastic particles on biota and humans has been increasing in recent years, studies on mixtures of plastics and other chemical contaminants in the aquatic environment are still limited. This review aims to gather information about the main characteristics of plastic particles that allow different types of contaminants to adsorb on their surfaces, the consequences of this adsorption, and the interactions of plastic particles with aquatic biota. Additionally, some missing links and potential solutions are presented to boost more research on this topic and achieve a holistic view on the effects of micro- and nanoplastics to biological systems in aquatic environments. It is urgent to implement measures to deal with plastic pollution that include improving waste management, monitoring key plastic particles, their hotspots, and developing their assessment techniques, using alternative products, determining concentrations of micro- and nanoplastics and the contaminants in freshwater and marine food-species consumed by humans, applying clean-up and remediation strategies, and biodegradation strategies.


Subject(s)
Environmental Pollutants , Water Pollutants, Chemical , Biodegradation, Environmental , Ecosystem , Microplastics , Plastics/chemistry , Plastics/toxicity , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
3.
J Hazard Mater ; 436: 129064, 2022 08 15.
Article in English | MEDLINE | ID: mdl-35580497

ABSTRACT

Freshwater ecosystems are subjected to plastic extensive pollution because they are the direct link between plastic wastes and marine ecosystems. The aim of this study was to assess the impacts of different sizes of polyethylene plastics (micro: µPs and macroplastics: PBs) on freshwater decomposers of plant litter. We exposed leaf associated microbial assemblages to µPs (0.5 or 1.5 g L-1) and discs of PBs as follows: green plastic bags (PB-G) alone or in mixtures with transparent plastic bags (PB-Mix). Then, we conducted a feeding preference experiment with the invertebrate shredder Limnephilus sp. to assess their capacity to distinguish leaf discs from PB discs of the same size (12 mm). Leaf decomposition, activities of fungal enzymes and sporulation were inhibited by µPs and PB-Mix, and shifts in fungal community composition were observed. The invertebrate shredders preferred to feed on leaves treated with µPs avoiding those exposed to PB-G/PB-Mix. Our results demonstrated that plastics can have a direct effect on stream-dwelling microbial decomposers and an indirect effect on higher trophic levels (shredders), highlighting that trophic transfer is a route of plastic exposure. The plastic properties (size, concentration, colour) appear to influence plastic toxicity to microbes and shredders, indicating the importance of considering physicochemical properties when assessing their risks to freshwater ecosystems.


Subject(s)
Food Chain , Rivers , Animals , Ecosystem , Invertebrates , Plant Leaves , Plastics/analysis , Plastics/toxicity , Rivers/chemistry
4.
Glob Chang Biol ; 28(1): 115-127, 2022 01.
Article in English | MEDLINE | ID: mdl-34651383

ABSTRACT

Mounting evidence points to a linkage between biodiversity and ecosystem functioning (B-EF). Global drivers, such as warming and nutrient enrichment, can alter species richness and composition of aquatic fungal assemblages associated with leaf-litter decomposition, a key ecosystem process in headwater streams. However, effects of biodiversity changes on ecosystem functions might be countered by the presumed high functional redundancy of fungal species. Here, we examined how environmental variables and leaf-litter traits (based on leaf chemistry) affect taxonomic and functional α- and ß-diversity of fungal decomposers. We analysed taxonomic diversity (DNA-fingerprinting profiles) and functional diversity (community-level physiological profiles) of fungal communities in four leaf-litter species from four subregions differing in stream-water characteristics and riparian vegetation. We hypothesized that increasing stream-water temperature and nutrients would alter taxonomic diversity more than functional diversity due to the functional redundancy among aquatic fungi. Contrary to our expectations, fungal taxonomic diversity varied little with stream-water characteristics across subregions, and instead taxon replacement occurred. Overall taxonomic ß-diversity was fourfold higher than functional diversity, suggesting a high degree of functional redundancy among aquatic fungi. Elevated temperature appeared to boost assemblage uniqueness by increasing ß-diversity while the increase in nutrient concentrations appeared to homogenize fungal assemblages. Functional richness showed a negative relationship with temperature. Nonetheless, a positive relationship between leaf-litter decomposition and functional richness suggests higher carbon use efficiency of fungal communities in cold waters.


Subject(s)
Ecosystem , Rivers , Biodiversity , Fungi , Plant Leaves , Temperature
5.
Environ Pollut ; 290: 118088, 2021 Dec 01.
Article in English | MEDLINE | ID: mdl-34523514

ABSTRACT

The commercial use and spread of silver nanoparticles (AgNPs) in freshwaters have greatly increased over the last decade. Both AgNPs and ionic silver (Ag+) released from nanoparticles are toxic to organisms and compromise ecosystem processes such as leaf litter decomposition. Yet little is known about how AgNPs affect multitrophic systems of interacting species. Furthermore, past work has focused on waterborne exposure with scarce attention given to effects mediated by the consumption of contaminated food. We assessed the importance of direct (via water) and indirect (via diet) AgNP exposure to a processing chain comprising leaf litter, fungi, a shredder (Gammarus pulex) and a collector (Habroleptoides confusa) in microcosms. Direct exposure to contaminated water for 15 days impaired microbial leaf decomposition by ∼50% and leaf-associated fungal biomass by ∼10%. Leaf consumption was reduced by ∼20% but only when G. pulex was exposed to silver via contaminated leaves. There was no effect on FPOM production. Ag + could impose oxidative stress on the shredders and collectors independent of exposure route, as indicated by increased catalase and glutathione S-transferase activities and decreased superoxide dismutase activity. The activity of a neuronal enzyme (cholinesterase) in collectors, but not shredders, also decreased by almost 50% when the animals were indirectly exposed to AgNP. Our results show that AgNPs and Ag+ may disrupt detrital processing chains through direct and indirect exposure routes, even at low concentrations. This highlights the importance of AgNP exposure pathways to interconnected stream biota and ecosystem processes for realistic assessments of risks to freshwater ecosystems.


Subject(s)
Metal Nanoparticles , Rivers , Animals , Ecosystem , Fresh Water , Metal Nanoparticles/toxicity , Plant Leaves , Silver/toxicity
6.
Rev. enferm. UFSM ; 11: e29, 2021. ilus, tab
Article in English, Portuguese | LILACS, BDENF - Nursing | ID: biblio-1177835

ABSTRACT

Objetivo: identificar os fatores associados ao tempo da morte de vítimas de trauma. Método: coorte retrospectiva que analisou laudos de autópsia de vítimas de trauma admitidas em 2015 no Instituto Médico Legal Central de São Paulo, Brasil. O tempo da morte foi identificado a partir do momento da ocorrência do trauma até a confirmação do óbito. O modelo linear generalizado foi aplicado para análise dos dados. Resultados: entre as 1.500 vítimas fatais (75,7% homens; idade média 49,7 anos), prevaleceram as quedas (33,5%), seguidas das agressões (27,8%). Os fatores associados ao tempo da morte foram número de regiões corporais afetadas (p<0,001), tipo de trauma (p<0,001), sexo (p=0,009), gravidade do trauma segundo New Injury Severity Score (p<0,001), agressões (p<0,001) e lesões autoprovocadas intencionalmente (p<0,001). Conclusão: mulheres, vítimas de traumas que envolveram intencionalidade de provocar a morte e com elevada gravidade apresentaram tempo de sobrevida reduzido após a(s) lesão(ões).


Objective: to identify factors associated to the time of death of trauma victims. Method: a retrospective cohort that analyzed autopsy reports of trauma victims admitted in 2015 at the Central Institute of Forensic Medicine of São Paulo, Brazil. The time of death was identified from the trauma moment to the confirmation of death. The generalized linear model was applied to analyze the data. Results: among the 1,500 fatal victims (75.7% were men; mean age of 49.7 years old), falls prevailed (33.5%), followed by aggressions (27.8%). The factors associated with the time of death were the number of body areas affected (p<0.001), type of trauma (p<0.001), gender (p=0.009), trauma severity according to the New Injury Severity Score (p<0.001), assaults (p>0.001), and intentionally self-harm injuries (p<0.001). Conclusion: women, victims of traumas with the intention of causing death and with high severity presented a reduced survival time after the injury(ies).


Objetivo: identificar los factores asociados al momento de la muerte de víctimas de traumatismos. Método: estudio de cohorte retrospectivo que analizó informes de autopsias de víctimas de traumatismos admitidas en 2015 en el Instituto Médico Legal Central de San Pablo, Brasil. El momento de la muerte se identificó a partir del momento en que sucedió el traumatismo hasta la confirmación de la muerte. Se aplicó el modelo lineal generalizado para el análisis de los datos. Resultados: entre las 1.500 víctimas fatales (75,7% de ellas hombres; media de edad de 49,7 años), prevalecieron las caídas (33,5%), seguidas por las agresiones (27,8%). Los factores asociados al momento de la muerte fueron la cantidad de áreas del cuerpo afectadas (p<0,001), el tipo de traumatismo (p<0,001), el sexo (p=0,009), la gravedad del traumatismo conforme al New Injury Severity Score (p<0,001), agresiones (p<0,001) y lesiones autoprovocadas intencionalmente (p<0,001). Conclusión: las mujeres, víctimas de traumatismos con intención de provocar la muerte y de alta gravedad presentaron un tiempo de sobrevida reducido después de la o las lesiones.


Subject(s)
Humans , Autopsy , Wounds and Injuries , Trauma Severity Indices , Risk Factors , Mortality
7.
Environ Toxicol Chem ; 39(7): 1429-1437, 2020 07.
Article in English | MEDLINE | ID: mdl-32445252

ABSTRACT

The effects of silver nanoparticles (AgNPs) have been largely explored, but there is still a lack of knowledge on their effects under the predicted changes in temperature as a consequence of climate change. The aim of the present study was to determine how leaf consumption by invertebrate shredders is affected by dietary exposure to AgNPs and AgNO3 and whether changes in temperature alter such effects. Also, responses of antioxidant enzymes were examined. In microcosms, the invertebrate shredder Limnephilus sp. was allowed to feed on alder leaves treated with AgNPs (5, 10, and 25 mg L-1 ) and AgNO3 (1 mg L-1 ) at 10, 16, and 23 °C (6 replicates). After 5 d, the animals were transferred to clean water and allowed to feed on untreated leaves. The higher leaf consumption by the shredder was related to temperature increase and to the contamination of leaves with AgNPs and AgNO3 . Results from enzymatic activities demonstrated that AgNP contamination via food induce oxidative and neuronal stress in the shredder: the activities of catalase and superoxide dismutase were positively correlated with total Ag accumulated in the animal body. Moreover, glutathione S-transferase activity was strongly associated with higher temperature (23 °C). Overall results indicated that the effects of toxicants on consumption rates and enzymatic activities are modulated by temperature and suggested that increases in temperature changes the AgNP effects on invertebrate shredder performance. Environ Toxicol Chem 2020;39:1429-1437. © 2020 SETAC.


Subject(s)
Aquatic Organisms/drug effects , Invertebrates/drug effects , Metal Nanoparticles/toxicity , Silver/toxicity , Temperature , Animals , Antioxidants/metabolism , Biomarkers/metabolism , Catalase/metabolism , Neurons/enzymology , Oxidation-Reduction , Plant Leaves/metabolism , Principal Component Analysis , Silver Nitrate , Stress, Physiological/drug effects , Superoxide Dismutase/metabolism
8.
J Trauma Nurs ; 27(2): 111-120, 2020.
Article in English | MEDLINE | ID: mdl-32132492

ABSTRACT

Fall represents an important cause of death and its relation with the population aging evidences the need of a broad analysis considering different aspects associated with its occurrence. The objective of this study was to compare fatal victims due to unintentional fall among adults, young olds, olds, and oldest olds, according to sociodemographic data, characteristics, and severity of the trauma. This study is a cross-sectional, comparative study analyzing autopsy reports of fatal victims due to fall, admitted to the Medical Legal Institute of Sao Paulo, Sao Paulo, Brazil, in 2015. The following age groups were: adults (≥18 and <60 years), young olds (≥60 and <70 years), olds (≥70 and <80 years), and oldest olds (≥80 years). The Pearson's χ, Fisher's exact, Kruskal-Wallis, and Dunn tests were applied to compare the groups, with a significance level of 5%. Regarding the 469 fatalities analyzed (57.8% males, mean age: 71.3 ± 18.2 years), there was a higher frequency of oldest olds (43.5%), ground-level falls (70.1%), femoral fractures (35.0%), and delayed deaths (79.6%) due to posttraumatic complications (57.2%). Adults, young olds, olds, and oldest olds differed significantly (p ≤ .005) in relation to the total of analyzed variables, with a special remark on the differences between the age extremes. High frequencies of femoral fractures and delayed deaths due to complications of treatment in low-severity fall victims, especially those older than 70 years, make it necessary to improve fall prevention programs in the older adults and to create a line of care for this population.


Subject(s)
Accidental Falls/mortality , Age Distribution , Adult , Aged , Aged, 80 and over , Autopsy , Brazil/epidemiology , Cause of Death , Cross-Sectional Studies , Female , Humans , Male , Middle Aged
9.
Sex., salud soc. (Rio J.) ; (31): 81-100, enero-abr. 2019. graf
Article in Portuguese | LILACS | ID: biblio-1004714

ABSTRACT

Resumo O presente artigo apresenta resultados uma pesquisa cujo tema compreendeu a lesbianidade na Internet. O Tumblr foi selecionado como lugar de análise, mais especificamente páginas de mulheres autoidentificadas como lésbicas ou que por meio dos conteúdos de seus Tumblrs demonstraram interesse no tema da lesbianidade. O material analisado compreendeu imagens retiradas dessas páginas. Neste artigo, o tema principal é o corpo, um dos âmbitos de análise que emergiram da pesquisa. A metodologia compreendeu estudos de imagem, com base em Rosa Fischer (2002), a desconstrução com base em Derrida (2002), e o referencial teórico foi fundamentado em conceitos de Foucault (2008, 2010), Judith Butler (2000, 2004, 2013) e Preciado (2002, 2008). As análises mostraram a sexualidade e o gênero como elementos que possibilitam a materialização da lesbianidade nos corpos das imagens analisadas por meio da ruptura com o regime mulher-feminina-heterossexual.


Abstract The article presents analyzed lesbianity on the Internet, with Tumblr selected as a place of analysis, specifically pages of women self-identified as lesbians or that through the contents of their Tumblrs showed interest lesbianity. The material analyzed comprised images taken from these pages. In this article, the main theme is the body, one of the scopes of analysis that emerged from the research. The methodology used was based on Rosa Fischer (2002), deconstruction based on Derrida (2002), and the theoretical reference based on concepts of Foucault (2008, 2010), Judith Butler (2000, 2004, 2013) and Preciado (2002, 2008). The analysis showed sexuality and gender as elements that allow the materialization of lesbianity in the bodies of the images analyzed through a rupture with the woman-female-heterosexual regime.


Resumen El presente artículo presenta resultados de una investigación cuyo tema comprendió la lesbianidad en la Internet. El Tumblr fue seleccionado como lugar de análisis, más específicamente páginas de mujeres auto-identificadas como lesbianas, y que por medio de los contenidos de sus Tumblrs demostraron interés en el tema de la lesbianidad. El material analizado comprendió imágenes retiradas de esas páginas. En este artículo, el tema principal es el cuerpo, uno de los ámbitos de análisis que emergió de la investigación. La metodología comprendió estudios de imagen, con base en Rosa Fischer (2002), la deconstrucción con base en Derrida (2002), y el referencial teórico fue fundamentado en conceptos de Foucault (2008, 2010), Judith Butler (2000, 2004, 2013) y Preciado (2002, 2008). Los análisis mostraron la sexualidad y el género como elementos que posibilitan la materialización de la lesbianidad en los cuerpos de las imágenes analizadas, por medio de la ruptura con el régimen mujer-femenina-heterosexual.


Subject(s)
Humans , Female , Body Image , Homosexuality, Female , Sexuality , Social Media/trends , Sociological Factors , Gender Identity
10.
Mar Environ Res ; 142: 59-68, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30274716

ABSTRACT

Changes in environmental conditions can influence sponges and their holobionts. The present study investigated the effect of upwelling and anthropogenic pollution on the bioactivity of marine sponges, microbial communities and functional genes, and composition of their chemical compounds. The species Dysidea etheria, Darwinella sp., Hymeniacidon heliophila and Tedania ignis were collected from areas with distinct influence of upwelling and low anthropogenic impact and from areas without influence of upwelling but affected by sewage and the port. In most cases, the same sponge species collected from areas with distinct environmental conditions had a different chemical composition, antifouling activity, composition and diversity of associated microorganisms. Antimicrobial, quorum sensing inhibitory and anti-larval activities of sponge extracts were more pronounced in the area without upwelling showing higher level of anthropogenic pollution. This study suggests that upwelling and anthropogenic pollution affect the chemical activity and holobiome composition of sponges.


Subject(s)
Environment , Microbiota/drug effects , Porifera/microbiology , Water Pollutants/toxicity , Animals , Aquatic Organisms/chemistry , Aquatic Organisms/drug effects , Aquatic Organisms/microbiology , Porifera/chemistry , Porifera/drug effects
11.
Sci Total Environ ; 601-602: 1324-1332, 2017 Dec 01.
Article in English | MEDLINE | ID: mdl-28605851

ABSTRACT

Silver nanoparticles (AgNP)s can have toxic effects on aquatic species and compromise important ecosystem processes. AgNP impacts have been the focus of much research, but their effects under different environmental contexts, such as the increase in global temperature are difficult to predict. The aim of this study was to evaluate the interactive effects of AgNPs and temperature on the activity and diversity of microbial decomposers of plant litter in streams. Litter-associated microbial communities were exposed in microcosms to increased concentrations of AgNPs (50 to 75000µgL-1) and AgNO3 (5 to 7500µgL-1) and kept for 21days at 10°C, 16°C and 23°C. Effects of AgNPs and AgNO3 were assessed based on leaf mass loss and litter-associated microbial communities by measuring microbial diversity, the activity of fungal extracellular enzymes, and fungal biomass and reproduction. Increase in temperature stimulated leaf mass loss, but not fungal biomass and reproduction. Increased AgNP and AgNO3 concentrations inhibited fungal reproduction and diversity, particularly at 23°C. Activities of the extracellular enzymes phenol oxidase and ß-glucosidase were generally higher at 23°C. Microbial communities were mainly structured by AgNP and AgNO3 concentrations more than by temperature. The negative effects of nano and ionic Ag on microbial activity were more pronounced at 10 and 23°C. The behavior of AgNPs was more related to water physical and chemical characteristics (pH) than to temperature. Results highlight the importance of considering different environmental scenarios when examining NP toxicity to freshwater biota and ecosystem processes.


Subject(s)
Fungi/physiology , Metal Nanoparticles/chemistry , Silver/chemistry , Temperature , Water Microbiology , Biodegradation, Environmental , Ecosystem , Fungi/drug effects , Rivers
12.
Org Biomol Chem ; 15(21): 4667-4680, 2017 May 31.
Article in English | MEDLINE | ID: mdl-28517004

ABSTRACT

The synthesis and anticancer evaluation of novel N-glycosyl derivatives containing N-substituted glucuronamide moieties, as nucleoside analogs or as prospective mimetics of glycosyl phosphates or of nucleotides, is reported. These compounds comprise N-anomerically-linked nucleobases or motifs that are surrogates of a phosphate group, such as sulfonamide or phosphoramidate moieties. 1-Sulfonamido glucuronamides containing N-benzyl, N-propargyl or N-dodecyl carboxamide units were synthesized through glycosylation of methanesulfonamide with tetra-O-acetyl glucuronamides. 1-Azido glucuronamides were accessed by microwave-assisted reactions of tetra-O-acetyl glucuronamides with TMSN3 and were further converted into N-glycosylphosphoramidates by treatment with trimethyl phosphite. Potential glucuronamide-based nucleotide mimetics comprising both an anomeric sulfonamide/phosphoramidate group and a benzyltriazolylmethyl amide system at C-5, as nucleobase mimetics, were synthesized via 'click' cycloaddition of N-propargyl glucuronamide derivatives with benzyl azide. N-Dodecyl tetra-O-acetyl glucuronamides were converted into uracil and purine nucleosides via N-glycosylation of the corresponding silylated nucleobases. Biological screening revealed significant antiproliferative activities of the N-dodecyl glucuronamide-containing sulfonamide, phosphoramidate and nucleosides in K562 and MCF-7 cells. The highest effect was exhibited by the N9-linked purine nucleoside in the breast cancer cell MCF-7 with a GI50 value similar to that of clinically used 5-fluorouracil. Immunoblotting and cell cycle analysis of K562 cells treated with the most active compound as well as evaluation of the effect of this nucleoside on the activities of caspases 3 and 7 showed induction of apoptosis as the mechanism of cell death.


Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Glucuronates/chemical synthesis , Glucuronates/pharmacology , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Chemistry Techniques, Synthetic , Glucuronates/chemistry , Glycosylation , Humans , K562 Cells , MCF-7 Cells
13.
Ecotoxicol Environ Saf ; 140: 148-155, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28254725

ABSTRACT

AgNP physicochemical properties may affect AgNP toxicity, but their effects on plant litter decomposition and the species driving this key ecosystem process in freshwaters have been poorly investigated. We assessed the impacts of AgNPs with different size and surface coating (100nm PVP (polyvinylpyrrolidone)-dispersant, 50-60nm and 35nm uncoated) on freshwater decomposers of leaf litter by exposing leaf associated microbial assemblages to increasing concentrations of AgNPs (up to 200mgL-1) and of AgNO3 (up to 25mgL-1). We further conducted a feeding preference experiment with a common invertebrate shredder, Limnephilus sp., which was allowed to feed on microbially-colonized leaves previously exposed to AgNPs and AgNO3. Leaf decomposition and microbial activity and diversity were inhibited when exposed to increased concentrations of 100nm AgNPs (≥25mgL-1), while microbial activity was stimulated by exposure to 35nm AgNPs (≥100mgL-1). Invertebrate shredders preferred leaves exposed to 35nm AgNPs (25mgL-1) and avoided leaves exposed to AgNO3 (≥2mgL-1). Results from the characterization of AgNPs by dynamic light scattering revealed that AgNps with PVP-dispersant were more stable than the uncoated AgNPs. Our results highlight the importance of considering the physicochemical properties of NPs when assessing their toxicity to litter decomposers in freshwaters.


Subject(s)
Invertebrates/drug effects , Metal Nanoparticles/toxicity , Microbial Consortia/drug effects , Quercus/chemistry , Rivers/chemistry , Silver/toxicity , Animals , Dose-Response Relationship, Drug , Ecosystem , Feeding Behavior/drug effects , Invertebrates/metabolism , Metal Nanoparticles/chemistry , Particle Size , Plant Leaves/chemistry , Plant Leaves/metabolism , Povidone/chemistry , Quercus/metabolism , Rivers/microbiology , Silver/chemistry , Surface Properties
14.
Nat Prod Bioprospect ; 2015 Oct 22.
Article in English | MEDLINE | ID: mdl-26493049

ABSTRACT

The inhibition of α-glucosidase and glucose-6-phosphatase, two enzymes involved in the carbohydrate metabolism, is an important target to control glycaemia on individuals with type 2 diabetes. In this work we report for the first time the inhibition of both enzymes by the antihyperglycemic n-butanol extract from Genista tenera (Fabaceae). This extract decreased α-glucosidase and glucose-6-phosphatase activities to 0.97 and 80.25 %, respectively, being more effective than acarbose, and phlorizin, the positive controls, which reduced enzymes activities only to 17.39 and 96.06 %. Once inflammation and oxidative stress are related to diabetic impairments, the anti-inflammatory activity of the extract was also evaluated, through its inhibitory activity over COX-1 enzyme (47.5 % inhibition). Moreover, after induction of oxidative stress by UV radiation, the viability of irradiated rat liver hepatoma cells exposed to the extract was significantly higher (67.82 %) than that promoted by ascorbic acid, the positive control (45.05 %). In addition, the stability of the extract under gastrointestinal conditions was evaluated by HPLC-DAD-ESI-MS/MS. Flavonoid diglycosides were identified as the main constituents of the extract, and no alterations in the chemical composition nor in the antioxidant activity were observed after in vitro digestion with artificial gastric and pancreatic juices.

15.
Phytother Res ; 28(9): 1329-34, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24633846

ABSTRACT

Artemisia gorgonum (Asteraceae) is an endemic plant to the Cape Verde islands and plays an important role in traditional medicine. The chloroform extract of the plant aerial parts afforded six sesquiterpene lactones, two methoxylated flavonoids, two lignans, and one tetracyclic triterpene, which were isolated by chromatographic methods and their structure established by physical and spectroscopic techniques. The cytotoxic activity of the three major constituents, namely, arborescin, artemetin, and sesamin, was evaluated on neuroblastoma (SH-SY5Y), hepatocarcinoma (HepG2), and nontumoral bone marrow stromal (S17) cell lines. The application of different concentrations of the compounds significantly decreased tumor cells viability at different extents, especially at the highest concentrations tested. Arborescin is the most promising compound as it was able to reduce tumoral cell viability with an IC50 significantly lower (229-233 µM; p < 0.01) than that of S17 cells (445 µM). Arborescin and artemetin were less toxic to nontumoral cells than the antitumoral drug tested, etoposide. Our results indicate that arborescin has a significant cytotoxic activity in vitro, more pronounced on the cancer cell lines, confirming A. gorgonum as a source of potential antitumoral molecules.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Artemisia/chemistry , Dioxoles/pharmacology , Flavonoids/pharmacology , Lignans/pharmacology , Plant Extracts/pharmacology , Sesquiterpenes, Guaiane/pharmacology , Animals , Antineoplastic Agents, Phytogenic/isolation & purification , Cell Line , Cell Line, Tumor , Dioxoles/isolation & purification , Flavonoids/isolation & purification , Humans , Lignans/isolation & purification , Mice , Plant Components, Aerial , Plant Extracts/chemistry , Sesquiterpenes, Guaiane/isolation & purification
16.
Environ Sci Pollut Res Int ; 21(9): 5785-94, 2014 May.
Article in English | MEDLINE | ID: mdl-24442965

ABSTRACT

In this study, we compared the usefulness of a long-living sponge (Hymeniacidon heliophila, Class Demospongiae) and a short-living one (Paraleucilla magna, Class Calcarea) as biomonitors of metallic pollution. The concentrations of 16 heavy metals were analyzed in both species along a gradient of decreasing pollution from the heavily polluted Guanabara Bay to the less impacted coastal islands in Rio de Janeiro, SE Brazil (SW Atlantic). The levels of most elements analyzed were higher in H. heliophila (Al, Co, Cr, Cu, Fe, Mn, Ni, Hg, Ni, and Sn) and P. magna (Ni, Cu, Mn, Al, Ti, Fe, Pb, Co, Cr, Zn, and V) collected from the heavily polluted bay when compared with the cleanest sites. Hymeniacidon heliophila accumulates 11 elements more efficiently than P. magna. This difference may be related to their skeleton composition, histological organization, symbiont bacteria and especially to their life cycle. Both species can be used as a biomonitors of metallic pollution, but while Hymeniacidon heliophila was more effective in concentrating most metals, Paraleucilla magna is more indicated to detect recent pollutant discharges due to its shorter life cycle. We suggest that the complementary use of species with contrasting life histories can be an effective monitoring strategy of heavy metals in coastal environments.


Subject(s)
Environmental Monitoring/methods , Metals, Heavy/analysis , Porifera/chemistry , Water Pollutants, Chemical/analysis , Animals , Bays/chemistry , Brazil , Ecosystem , Environment , Seawater/chemistry
17.
Mar Environ Res ; 92: 234-43, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24183652

ABSTRACT

The present study evaluates the potential of Hymeniacidon heliophila as bioindicator of PAH contamination. For this, concentration of 33 PAH was determined in organisms from sites with different contamination level including the heavily polluted Guanabara Bay, Rio de Janeiro, and less impacted coastal areas. PAH concentration and typology were determined in sponges collected from different depths and in two different seasons. The brown mussel broadly studied as bioindicator was also sampled from the same sites for comparison. Both species provided similar information on total PAH concentration which is related to site contamination level. Sponges, however, revealed slight tendency to accumulation of combustion-derived PAH in relation to petrogenic compounds. Differences in PAH typology between species may derive from the interspecific variation in particle size ingestion. Different hydrocarbon typologies were observed in sponges from dry and wet season and PAH concentration varied with depth. H. heliophila may be used as an alternative approach to investigate the presence and sources of PAH in estuarine areas.


Subject(s)
Environmental Monitoring/methods , Polycyclic Aromatic Hydrocarbons/analysis , Porifera , Water Pollutants, Chemical/analysis , Animals , Brazil , Particle Size , Perna , Polycyclic Aromatic Hydrocarbons/pharmacokinetics , Porifera/metabolism , Water Pollutants, Chemical/pharmacokinetics
18.
Mol Biol Rep ; 39(12): 10121-30, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22932942

ABSTRACT

Oxidative stress plays an important role in the pathogenesis of diabetes and its complications. Genetic variations of enzymes producing reactive oxygen species could change their activity, thus contributing to the susceptibility to oxidative stress. The aim of this study was to examine the role of the NADPH oxidase C242T polymorphism in the development of carotid atherosclerosis in patients with type 2 diabetes. 286 diabetic patients and 150 healthy controls were enrolled in the study. Carotid atherosclerosis was quantified ultrasonographically as carotid intima-media thickness, plaque score (0-6) and plaque type (1-5). Diabetic patients were divided into low and high risk groups based on ultrasound phenotypes of carotid atherosclerosis. Genotypes were determined by real-time PCR. Levels of 8-hydroxy-2-deoxyguanosine (8-OHdG) were measured by enzyme-linked immunosorbent assay (ELISA). Diabetic patients demonstrated a statistically significant difference compared to healthy controls in the following parameters: age, BMI, waist circumference, smoking prevalence, glucose, triglyceride and 8-OHdG serum levels. Control subjects had significantly higher levels of HDL, LDL and total cholesterol than diabetics (p < 0.001). The NADPH C242T polymorphism was not related with clinical characteristics, lipid parameters and 8-OHdG serum levels. We found no significant difference in the NADPH genotype distribution between diabetics and controls (p = 0.19) nor between low and high risk subgroups of diabetics (mean CIMT: p = 0.67; plaque score: p = 0.49, plaque type: p = 0.56). In the present study the NADPH C242T polymorphism was not associated with the degree of oxidative stress and carotid atherosclerosis. Further studies will show if it can be used as a genetic marker for carotid atherosclerosis in diabetic patients.


Subject(s)
Carotid Artery Diseases/genetics , Diabetes Mellitus, Type 2/genetics , NADPH Oxidases/genetics , Polymorphism, Single Nucleotide , 8-Hydroxy-2'-Deoxyguanosine , Adult , Aged , Carotid Arteries/diagnostic imaging , Carotid Arteries/pathology , Carotid Artery Diseases/blood , Carotid Artery Diseases/enzymology , Carotid Artery Diseases/etiology , Case-Control Studies , Cross-Sectional Studies , Deoxyguanosine/analogs & derivatives , Deoxyguanosine/blood , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/enzymology , Female , Gene Frequency , Genetic Association Studies , Humans , Male , Middle Aged , Multivariate Analysis , Oxidative Stress , Plaque, Atherosclerotic/diagnostic imaging , Plaque, Atherosclerotic/pathology , Risk Factors , Sequence Analysis, DNA , Slovenia , Statistics, Nonparametric , Ultrasonography
19.
PLoS One ; 5(12): e15774, 2010 Dec 30.
Article in English | MEDLINE | ID: mdl-21209889

ABSTRACT

BACKGROUND: Archaea are ubiquitous symbionts of marine sponges but their ecological roles and the influence of environmental factors on these associations are still poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: We compared the diversity and composition of archaea associated with seawater and with the sponges Hymeniacidon heliophila, Paraleucilla magna and Petromica citrina in two distinct environments: Guanabara Bay, a highly impacted estuary in Rio de Janeiro, Brazil, and the nearby Cagarras Archipelago. For this we used metagenomic analyses of 16S rRNA and ammonia monooxygenase (amoA) gene libraries. Hymeniacidon heliophila was more abundant inside the bay, while P. magna was more abundant outside and P. citrina was only recorded at the Cagarras Archipelago. Principal Component Analysis plots (PCA) generated using pairwise unweighted UniFrac distances showed that the archaeal community structure of inner bay seawater and sponges was different from that of coastal Cagarras Archipelago. Rarefaction analyses showed that inner bay archaeaoplankton were more diverse than those from the Cagarras Archipelago. Only members of Crenarchaeota were found in sponge libraries, while in seawater both Crenarchaeota and Euryarchaeota were observed. Although most amoA archaeal genes detected in this study seem to be novel, some clones were affiliated to known ammonia oxidizers such as Nitrosopumilus maritimus and Cenarchaeum symbiosum. CONCLUSION/SIGNIFICANCE: The composition and diversity of archaeal communities associated with pollution-tolerant sponge species can change in a range of few kilometers, probably influenced by eutrophication. The presence of archaeal amoA genes in Porifera suggests that Archaea are involved in the nitrogen cycle within the sponge holobiont, possibly increasing its resistance to anthropogenic impacts. The higher diversity of Crenarchaeota in the polluted area suggests that some marine sponges are able to change the composition of their associated archaeal communities, thereby improving their fitness in impacted environments.


Subject(s)
Archaea/metabolism , Porifera/metabolism , Ammonia/chemistry , Animals , Biodiversity , Brazil , Ecology , Environment , Models, Genetic , Molecular Sequence Data , Phylogeny , Plankton , Principal Component Analysis , RNA, Ribosomal, 16S/metabolism , Seawater
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