Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 62
Filtrar
1.
Arch Environ Contam Toxicol ; 86(1): 58-72, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38103085

RESUMO

Alterations in ivermectin (IVM, 22,23-dihydro avermectin B1a+22,23-dihydro avermectin B1b) toxicokinetics following P-glycoprotein (P-gp) induction by clotrimazole (CTZ) were examined in rainbow trout (Oncorhynchus mykiss) to assess the potential importance of P-gp activity levels in xenobiotic distribution and kinetics in fish. Control and fish pretreated with CTZ (30 µmol/kg) were administered 175 µg/kg 3H-IVM into the caudal vasculature. At various time points (0.25, 0.5, 1, 3, 24, 48, 96, and 168 h) following injection, tissues (blood, liver, kidney, gill, intestines, brain [5 regions], eye, gonad and fat) were removed analyzed for IVM-derived radioactivity. IVM concentration declined in blood, liver, kidney and gill, and concentrations in other tissues remained constant over the sampling period. The highest measured concentrations were found in kidney, followed by liver, with the lowest values found in brain, eye and gonad. The highest % of the administered dose was found in the liver and kidney in the immediate hours post-administration, and in the intestines and fat at 24 h post-administration. P-gp induction by CTZ did not alter IVM distribution or any calculated toxicokinetic parameter (AUC, mean residence time, T1/2, clearance rate, volume of distribution), suggesting that P-gp induction may be limited or that P-gp plays a lesser role in xenobiotic kinetics in fish compared to mammals.


Assuntos
Ivermectina , Oncorhynchus mykiss , Animais , Ivermectina/toxicidade , Oncorhynchus mykiss/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Toxicocinética , Xenobióticos , Fígado/metabolismo , Mamíferos/metabolismo
2.
PLoS One ; 18(11): e0293333, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37922315

RESUMO

Back pain in athletes varies with sport, age, and sex, which can impair athletic performance, thereby contributing to retirement. Studies on back pain in this population use questionnaires to assess components, such as pain intensity and location and factors associated with pain, among others. This study aimed to review validated questionnaires that have assessed back pain in athletes. This systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) by searching the databases Embase, MEDLINE, SPORTDiscus, CINAHL, and Scopus. The articles were selected regardless of language and date of publication. Titles and abstracts were independently selected by two reviewers; disagreements were resolved by a third reviewer. All the steps were conducted using the software Rayyan. The methodological quality of the questionnaire validation articles was assessed using a critical appraisal tool checklist proposed by Brink and Louw. The search returned 4748 articles, of which 60 were selected for this review, including 5 questionnaire validation studies. These articles were published between 2004 and 2022, which were performed in more than 20 countries, particularly Germany (14) and Sweden (5). Thirteen different instruments were identified, of which 46.1% were developed in Europe. The most commonly used questionnaires were the Oswestry Disability Index and Nordic Standardized Questionnaire. In addition, five questionnaire validation studies were selected for methodological quality assessment, with only two studies demonstrating high methodological quality. The following three instruments were identified for assessing back pain specifically in athletes: Micheli Functional Scale, Persian Functional Rating Index, and Athlete Disability Index. This review confirmed that all three instruments were specifically designed to assess this condition.


Assuntos
Desempenho Atlético , Pessoas com Deficiência , Dor Lombar , Humanos , Atletas , Europa (Continente)
3.
Artigo em Inglês | MEDLINE | ID: mdl-37689171

RESUMO

The neuroprotective effects of inducing the blood-brain barrier ATP-binding cassette protein transporter P-glycoprotein (P-gp) with clotrimazole (CTZ) in both fed and fasted zebrafish (Danio rerio) against the CNS-toxicant ivermectin (IVM, 22,23-dihydro avermectin B1a + 22,23-dihydro avermectin B1b) were examined. Zebrafish were administered 2 µmol/kg IVM intraperitoneally, and various behavioural assays (swimming performance, exploratory behaviour, olfactory responses, motor coordination, and escape responses) were used to measure neurological dysfunction. IVM administration alone caused a decrease in mean swim speed (91 % of controls), maximal speed (71 %), passage rate (81 %), 90° turns (81 %), and response to food stimulus (39 %). IVM exposure also increased the percent time that fish spent immobile (45 % increase over controls) and the percent of lethargic fish (40 % increase). Fish administered 30 µmol/kg of the P-gp inducer CTZ intraperitoneally 3 d prior to IVM exposure exhibited a change in only the % time spent immobile. These data indicate that P-gp induction may be limited in protecting the zebrafish CNS from IVM over baseline. Fasted fish did not differ from fed fish in the effects of IVM on behaviour, and no differences were seen following P-gp induction with CTZ. These results suggest that this chemical defence system is not downregulated when fish are challenged with limited energy availability.

4.
Chemosphere ; 340: 139730, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37574089

RESUMO

Mangroves represent a challenge in monitoring studies due to their physical and chemical conditions under constant marine and anthropogenic influences. This study investigated metals/metalloids whole-body bioaccumulation (soft tissues) and the risk associated with their uptake, biochemical and morphological detoxification processes in gills and metals/metalloids immobilisation in shells of the neotropical sentinel oyster Crassostrea rhizophorae from two Brazilian estuarine sites. Biochemical and morphological responses indicated three main mechanisms: (1) catalase, superoxide dismutase and glutathione played important roles as the first defence against reactive oxygen species; (2) antioxidant capacity against peroxyl radicals, glutathione S-transferase, metallothionein prevent protein damage and (3) metals/metalloids sequestration into oyster shells as a mechanism of oyster detoxification. However, the estimated daily intake, target hazard quotient, and hazard index showed that the human consumption of oysters would not represent a human health risk. Among 14 analysed metals/metalloids, chemometrics indicate that Mn, As, Pb, Zn and Fe overload the antioxidant system leading to morphological alterations in gills. Overall, results indicated cellular vacuolization and increases in mucous cell density as defence mechanisms to prevent metals/metalloids accumulation and the reduction in gill cilia; these have long-term implications in respiration and feeding and, consequently, for growth and development. The integration of data from different sites and environmental conditions using chemometrics highlights the main biological patterns of detoxification from a neotropical estuarine bivalve, indicating the way in which species can cope with metals/metalloids contamination and its ecological consequences.


Assuntos
Crassostrea , Metaloides , Poluentes Químicos da Água , Animais , Humanos , Antioxidantes/metabolismo , Metaloides/análise , Quimiometria , Metais/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos
5.
Aquat Toxicol ; 262: 106640, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37595501

RESUMO

Graphene oxide (GO) and reduced graphene oxide (rGO) are both widely applicable and there is a massive production throughout the world which imply in inevitable contamination in the aquatic environment by their wastes. Nevertheless, information about their interaction at the cellular level in fish is still scarce. We investigated the metabolic activity, reactive oxygen species (ROS) production, responses of antioxidant defenses, and total antioxidant capacity (TAC) as well as oxidative stress and DNA integrity in zebrafish liver cells (ZFL) exposed to (0.001, 0.01, 0.1 and 1 µg mL-1) of GO and rGO after two exposure period (24 and 72 h). Higher ROS production and no significant changes in the antioxidant defenses resulted in lipid peroxidation in cells exposed to rGO. Cells exposed to GO increased the activity of antioxidant defenses sustaining the TAC and avoiding lipid peroxidation. Comet assay showed that both, GO and rGO, caused DNA strand breaks after 24 h of exposure; however, only rGO caused DNA damage after 72 h of exposure. The exposure to rGO was significantly more harmful to ZFL cells than GO, even at very low concentrations. The cells showed a high capacity to neutralize ROS induced by GO preventing genotoxic effects and metabolic activity, thus sustaining cell viability. The time of exposure had different impacts for both nanomaterials, GO caused more changes in 24 h showing recovery after 72 h, while cells exposed to rGO were jeopardized at both exposure times. These results indicate that the reduction of GO by removal of the oxygen functional groups (rGO) increased toxicity leading to adverse effects in the cells, even at very low concentrations.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Antioxidantes , Espécies Reativas de Oxigênio , Poluentes Químicos da Água/toxicidade , Estresse Oxidativo , Dano ao DNA , Fígado
6.
Sci Total Environ ; 902: 166119, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37567312

RESUMO

Settleable atmospheric particulate matter (SeAPM) containing a mixture of metals, including metallic nanoparticles, has increased throughout the world, and caused environmental and biota contamination. The metal bioconcentration pattern in Nile tilapia (Oreochromis niloticus) was evaluated during a 30-day exposure to 1 g L-1 SeAPM and assessed the human health risk from consuming fish fillets (muscle) based on the estimated daily intake (EDI). SeAPM was collected surrounding an iron ore processing and steel industrial complex in Vitória city (Espírito Santo, Brazil) area. Water samples were collected daily for physicochemical analyses, and every 3 days for multi-elemental analyses. Metal bioconcentrations were determined in the viscera and fillet of fish every 3 days. The elements B, Al, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Rb, Sr, Ag, Cd, Pb, Hg, Ba, Bi, W, Ti, Zr, Y, La, Nb, and Ce were analyzed in SeAPM, water, and fish using inductively coupled plasma mass spectrometry. The metal concentration in SeAPM-contaminated water was higher than in control water. Most metals bioconcentrated preferentially in the fish viscera, except for the Hg and Rb, which bioconcentrated mostly in the fillet. The bioconcentration pattern was Fe > Al > Mn > Pb > V > La > Ce > Y > Ni > Se > As > W > Bi in the viscera; it was higher than the controls throughout the 30-day exposure. Ti, Zr, Nb, Rb, Cd, Hg, B, and Cr showed different bioconcentration patterns. The Zn, Cu, Sr, Sn, Ag, and Ta did not differ from controls. The differences in metal bioconcentration were attributed to diverse metal bioavailability in water and the dissimilar ways fish can cope with each metal, including inefficient excretion mechanisms. The EDI calculation indicated that the consumption of the studied fish is not safe for children, because the concentrations of As, La, Zr, and Hg exceed the World Health Organization's acceptable daily intake for these elements.


Assuntos
Mercúrio , Metaloides , Metais Pesados , Poluentes Químicos da Água , Animais , Criança , Humanos , Bioacumulação , Cádmio/análise , Material Particulado/análise , Chumbo/análise , Mercúrio/análise , Metaloides/análise , Água/análise , Metais Pesados/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise
7.
Fish Physiol Biochem ; 48(5): 1267-1283, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36006557

RESUMO

The role of the blood-brain barrier ATP-binding cassette protein transporter P-glycoprotein (P-gp) in protecting zebrafish (Danio rerio) from the central nervous system neurotoxicant ivermectin (IVM, 22,23-dihydroavermectin B1a + 22,23-dihydroavermectin B1b) was examined in the absence and presence of the competitive inhibitor cyclosporin A (CsA). Zebrafish injected intraperitoneally with 1, 2, 5, or 10 µmol/kg IVM exhibited mortality 30 min following administration at the highest dose. At sublethal doses > 1 µmol/kg, IVM altered the swimming performance, exploratory behaviour, motor coordination, escape response and olfactory response in exposed fish. When fish were exposed to IVM in the presence of CsA, alterations in swimming and behaviours increased significantly and at the highest IVM/CsA ratio resulted in a complete lack of exploratory and olfactory behaviours. In separate experiments, fish were either fed or fasted, and the effects of IVM and CsA administration were examined. The effects of IVM administration and the exacerbated effects seen with CsA co-administration were not affected by fasting. This study provides evidence that P-gp provides a protective role in the BBB of fish against environmental neurotoxicants. The results also show that P-gp activity is maintained even under conditions of food deprivation, suggesting that this chemical defence system is prioritized over other energy expenditures during diet limitation.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Ivermectina , Animais , Ivermectina/toxicidade , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Peixe-Zebra/metabolismo , Ciclosporina/metabolismo , Jejum , Subfamília B de Transportador de Cassetes de Ligação de ATP , Trifosfato de Adenosina
8.
PLoS One ; 17(4): e0265913, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35377905

RESUMO

Physical inactivity commonly occurs throughout one's life, particularly during adolescence and young adulthood. Multiple factors can negatively influence participation in physical activity, but there has been no review examining the barriers to physical activity among high school and university students. Therefore, the aim of this systematic review was to summarize evidence of barriers to the practice of physical activity among high school and university students. The literature search was conducted without time limits using five databases, including CINAHL, Cochrane Library, Embase, PubMed, and Scopus. In total, 59 studies (37 with high school students [n = 22,908] and 22 with university students [n = 15,411]) were included. The main barriers identified in high school and university students were lack of time, lack of motivation, and lack of accessible places. These findings may be useful in designing and implementing evidence-informed interventions and programs for physical activity promotion in students.


Assuntos
Exercício Físico , Estudantes , Adolescente , Adulto , Humanos , Universidades , Adulto Jovem
10.
Sci Total Environ ; 770: 144651, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33736395

RESUMO

Mangroves are complex ecosystems with widely varying abiotic factors such as salinity, pH, redox potential, substratum particle size, dissolved organic matter and xenobiotic concentrations, and a high biodiversity. This paper presents the trophodynamic pathways of accumulation and transfer of metals and metalloids (B, Al, V, Cr, Mn, Fe, Ni, Cu, Zn, Ag, As, Se, Rb, Sr, Pb and Hg), in three trophic chains (plant-crab-fish, plankton-shrimp-fish and plankton-oyster) of similar food webs, corresponding to two mangrove estuaries (Santa Cruz and Vitória Bay, separated by 70 km) in the Espírito Santo State (Brazil). Although the trophic transfer patterns are affected by physical variables, metal and metalloids were found in all trophic levels. We observed similar trophodynamics between both estuaries with some elements, but unequal transfer patterns in other cases, thus questioning the effectiveness of 15N to determine the food chain when the aquatic biota is affected by anthropogenic contaminants. Thus, in the Santa Cruz estuary, most metals were biomagnified through the food web. Conversely, Vitória Bay presented mostly biodilution, suggesting that metal/metalloid transference patterns in mangrove ecosystems may be affected by different anthropogenic contamination inputs. These results indicate the importance of knowing the complete food web when evaluating the trophic transfer of elements, including an evaluation of the differential impact of pollution on diverse components of the food chain.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Animais , Brasil , Ecossistema , Monitoramento Ambiental , Estuários , Metais Pesados/análise , Poluentes Químicos da Água/análise
11.
Sci Total Environ ; 753: 141976, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32889320

RESUMO

Air pollution legislation and control worldwide is based on the size of particulate matter (PM) to evaluate the effects on environmental and human health, in which the small diameter particles are considered more dangerous than larger sizes. This study investigates the composition, stability, size and dispersion of atmospheric settleable particulate matter (SePM) in an aqueous system. We aimed to interrogate the changes in the physical properties and characteristics that can contribute to increased metal uptake by aquatic biota. Samples collected in an area influenced by the steel and iron industry were separated into 8 fractions (425 to ≤10 µm) and analysed physically and chemically. Results from ICP-MS and X-ray showed that the PM composition was mainly hematite with 80% of Fe, followed by Al, Mn and Ti. Among 27 elements analysed we found 19 metals, showing emerging metallic contaminants such as Y, Zr, Sn, La, Ba and Bi. Scanning electron microscopy (SEM) showed that SePM fractions are formed by an agglomeration of nanoparticles. Furthermore, dynamic light scattering (DLS), zeta potential and nanoparticle tracking analysis (NTA) demonstrated that SPM were dissociated in water, forming nanoparticles smaller than 200 nm, which can also contribute to water pollution. This study highlights that SePM contamination may be substantially higher than expected under that allowed in atmospheric regulatory frameworks, thereby extending their negative effect to water bodies upon settling, which is an underexplored area of our knowledge. We therefore provide important insights for future investigations on safety regulations involving SePM in the environment, indicating the need to revise the role of SePM, not solely associated with air pollution but also considering their deleterious effects on water resources.

12.
J Hazard Mater ; 408: 124424, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33183835

RESUMO

Emerging metallic contaminants (EMCs) are of concern due their presence in aquatic ecosystems and the lack of environmental regulations in several countries. This study verifies the presence of EMCs in two neotropical mangrove estuarine ecosystems (Espírito Santo Brazil) by evaluating abiotic and biotic matrices across six trophic levels (plankton, oyster, shrimp, mangrove trees, crabs and fish) and hence interrogates the trophic transfer of these elements and their possible input sources. Using the oyster Crassostrea rhizophorae as a biomonitor, ten EMCs (Bi, Ce, La, Nb, Sn, Ta, Ti, W, Y and Zr) were determined. Bi input was from iron export and pelletizing industries; Ce, La and Y inputs were mainly associated with solid waste from steel production, while Zr, Nb and Ti were related to atmospheric particulate matter emissions. EMCs were detected at various trophic levels, showing biomagnification for most of them in the Santa Cruz estuary but biodilution in Vitória Bay. These contrasting results between the estuaries could be attributed to different pollution degrees, needing further research to be fully understood. This is the first report demonstrating EMCs trophic pathways in situ, constituting an essential baseline for future research and safety regulations involving EMCs in the environment.


Assuntos
Cadeia Alimentar , Poluentes Químicos da Água , Animais , Brasil , Ecossistema , Monitoramento Ambiental , Estuários , Peixes , Poluentes Químicos da Água/análise
14.
Healthcare (Basel) ; 8(4)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33561044

RESUMO

Back pain is a public health problem that affects adolescents and adults worldwide. However, studies on back pain present inconsistent findings in part due to the use of different instruments, especially for athletes. Therefore, the objective of this systematic review protocol was to map the existing evidence on such tools. The systematic review will be conducted according to PRISMA guidelines. Five electronic databases, Embase, MEDLINE, SPORTDiscus, CINAHL, and Scopus will be searched. This review includes studies that investigated prevalence, incidence, and other variables. Titles and abstracts will be selected. Two independent reviewers will read the articles carefully and discrepancies, if any, will be dealt with by a third reviewer. All steps will be completed with Rayyan for systematic reviews and the methodological quality will be analyzed with a COSMIN checklist. Discussion: This systematic review will gather evidence on tools that assess back pain in athletes. The findings may indicate the most appropriate tools for assessing back pain. They will contribute to better reliability, safe measurements, and help to standardize a comparison tool between different studies. They will also assist in the development of specific tools for athletes. Registration: This review was submitted and registered under CRD42020201299 in PROSPERO.

15.
Environ Toxicol ; 34(4): 457-468, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30604913

RESUMO

The toxicity of titanium dioxide nanoparticles (TiO2 -NP) in the blood, liver, muscle, and brain of a Neotropical detritivorous fish, Prochilodus lineatus, was tested. Juvenile fish were exposed to 0, 1, 5, 10, and 50 mg L-1 of TiO2 -NP for 48 hours (acute exposure) or 14 days (subchronic exposure) to evaluate changes in hematology, red blood cell (RBC) genotoxicity/mutagenicity, liver function (reactive oxygen species (ROS) production, antioxidant responses, detoxification, and histopathology), acetylcholinesterase (AChE) activity in muscles and brain, and Ti bioaccumulation. TiO2 -NP did not cause genetic damage to RBC, but acutely decreased white blood cells (WBC) and increased monocytes. Subchronically, RBC decreased, mean cell volume and hemoglobin increased, and WBC and lymphocytes decreased. Therefore, NP has the potential to affect immune system and increase energy expenditure, reducing the fish's ability to avoid predator and to resist pathogens. In the liver, acute exposure decreased ROS and increased glutathione (GSH) content, while subchronic exposure decreased superoxide dismutase activity and increased glutathione-S-transferase (GST) activity and GSH content. GSH and GST seem to play an essential role in metabolizing NP and ROS, likely increasing hepatocytes' metabolic rate, which may be the cause of observed cell hypertrophy, disarrangement of hepatic cords and degenerative morphological alterations. Although most studies indicate that the kidney is responsible for metabolizing and/or eliminating TiO2 -NP, this study shows that the liver also has a main role in these processes. Nevertheless, Ti still accumulated in the liver, muscle, and brain and decreased muscular AChE activity after acute exposure, showing neurotoxic potential. More studies are needed to better understand the biochemical pathways TiO2 -NP are metabolized and how its bioaccumulation may affect fish homeostasis and survival in the environment.


Assuntos
Encéfalo/efeitos dos fármacos , Caraciformes/sangue , Fígado/efeitos dos fármacos , Músculos/efeitos dos fármacos , Nanopartículas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Contagem de Células Sanguíneas , Encéfalo/enzimologia , Encéfalo/patologia , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Eritrócitos/patologia , Fígado/enzimologia , Fígado/patologia , Músculos/enzimologia , Músculos/patologia , Nanopartículas/metabolismo , Titânio/metabolismo , Poluentes Químicos da Água/metabolismo
16.
Sci Total Environ ; 658: 798-808, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30583175

RESUMO

Intracellular titanium dioxide nanoparticles (TiO2-NP) with rutile crystalline form and dimensions varying from 43 to 67 nm × 64 to 93 nm are reported for the first time as being sequestered from the environment. TiO2-NP were identified inside all organs/tissues (muscle, kidney, gonad, hepatopancreas and gill) in both the cytoplasm and nucleus of the neotropical fish Centropomus parallelus, captured in an area affected by metallurgical activity. Atmospheric particulate matter (PM) sampled in the same area showed the presence of TiO2-NP with the same rutile crystalline form and dimensions varying from 16 to 93 nm × 45 to 193 nm, thus indicating the smelting and iron processing industries as the most probable source of TiO2-NP. In any sample, chemical analyses identify and quantify Ti concentration and nanocrystallography identified the structure of TiO2-NP. The Ti concentration in the sediment and atmospheric PM varied between years and it was mirrored by the Ti concentration in the fish organs. The gill has a higher Ti concentration varying from 5.50 to 14.57 µg g-1 dry weight and the gonad was the organ with lowest Ti level, 0.25 to 0.87 µg g-1 dry weight. In the muscles, Ti concentration varied from 0.85 to 3.34 µg g-1 dry weight. This contamination may be likely to affect the surrounding biota and food uptake, including the humans living in the city close to the metallurgical complex. These findings emphasised the needs to improve methods to reduce PM (including nanoparticles) arising from human activities and to evaluate the toxicokinetic and effects of TiO2-NP in the biota and human health.


Assuntos
Monitoramento Ambiental , Nanopartículas Metálicas , Perciformes/metabolismo , Titânio/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Transporte Biológico , Cristalografia , Estuários , Sedimentos Geológicos/análise , Nanopartículas Metálicas/análise , Oxirredução , Distribuição Tecidual , Titânio/análise , Poluentes Químicos da Água/análise
17.
Environ Sci Pollut Res Int ; 25(23): 22963-22976, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29858996

RESUMO

This study investigated the action of titanium dioxide nanoparticles (TiO2-NPs), on the gills and kidneys of Neotropical freshwater fish, Prochilodus lineatus, with emphasis on reactive oxygen species (ROS) production, antioxidant responses, and morphological changes. Fish were exposed to 1, 5, 10, and 50 mg L-1 nominal TiO2-NPs suspended into water for 2 or 14 days. In gills, ROS decreased and glutathione (GSH) increased after 2 days, while ROS and GSH increased and superoxide dismutase activity decreased after 14 days. In kidneys, GSH and lipoperoxidation increased after 2 days and catalase activity decreased after 14 days. Common histopathologies in gills were epithelium hyperplasia, cellular hypertrophy, proliferation of mitochondria-rich cells (MRC), and lamellar stasis; in kidneys, there were cellular and nuclear hypertrophy, focal tubule degeneration, necrosis, and melanomacrophage (MM) proliferation. Although environmentally unlikely, high-dose exposures clarified biological effects of TiO2-NPs, such as ROS formation and MRC responses in the gills, which may impair ionic balance. It was also found that MM are likely responsible for eliminating NPs in the kidney. These findings will help to regulate TiO2-NP disposal, but longer-term studies are still needed.


Assuntos
Caraciformes/metabolismo , Ecotoxicologia/métodos , Biomarcadores Ambientais , Nanopartículas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/análise , Antioxidantes/metabolismo , Água Doce , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Brânquias/patologia , Glutationa/análise , Glutationa/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Fígado/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Nanopartículas/química , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Testes de Toxicidade Aguda , Poluentes Químicos da Água/química
18.
Ecotoxicol Environ Saf ; 161: 260-269, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29886313

RESUMO

Metal/metalloid accumulation in fish organs elicits biochemical responses indicating the overall fish and environmental health status. This study evaluated the bioaccumulation of metals and metalloid in relation to a suite of biochemical biomarkers (superoxide dismutase, catalase, glutathione-S-transferase, Na+/K+-ATPase, H+-ATPase, acetylcholinesterase activities and the levels of glutathione, metallothionein, lipid peroxidation and oxidized protein) in different organs of fish, Centropomus parallelus, in Vitória Bay and Santa Cruz estuaries (State of Espírito Santo, Brazil) with distinct contamination levels. Metal and metalloid concentrations differ in each organ and were significantly higher in winter than in summer. Chemometric evaluation performed between metal/metalloid accumulation and the biomarkers revealed a complex scenario in which the biomarker responses depend on both metal accumulation and organ/tissue sensitivity. The metal levels in gills indicate fish contamination mainly via water and the low sensitivity of this organ to most metals. Biomarker responses suggested that the metal elimination pathway is through the gills and kidney. The hepatopancreas and kidneys were the most important detoxification organs while muscle was the less reactive tissue. In general, the finding suggested that, C. parallelus is partly able to tolerate such metal contamination. However, it is emphasized that the biomarker responses imply an energetic cost and may affect the growth rate and reproduction. Given the ecological and economic importance of C. parallelus, the level of toxic metals/metalloids in juvenile fish is an important early-warning for the maintenance, conservation and commercial use of this species.


Assuntos
Estuários , Metaloides/metabolismo , Metais/metabolismo , Perciformes/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Brasil , Brânquias/enzimologia , Brânquias/metabolismo , Hepatopâncreas/enzimologia , Hepatopâncreas/metabolismo , Peroxidação de Lipídeos , Alimentos Marinhos/análise
19.
Aquat Toxicol ; 200: 168-177, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29772474

RESUMO

Manufactured titanium dioxide nanoparticles (TiO2-NP) have been intensely applied in numerous industrial products and may be a risk for aquatic systems as they are not completely removed from domestic and industrial wastes after water treatment. This study evaluated the osmo- and ionic balance, Na+/K+-ATPase, H+-ATPase and carbonic anhydrase activities and the mitochondria-rich cells (MRC) in the gills and kidney of the Neotropical fish Prochilodus lineatus after 2 (acute) and 14 (subchronic) days of exposure to nominal 0, 1, 5, 10 and 50 mg L-1 TiO2-NP. The nominal concentrations corresponded to 0.0, 0.6, 1.6, 2.7 and 18.1 mg L-1 suspended TiO2-NP, respectively, in the water column one hour after NP introduction and were maintained for at least 24 h. Acute exposure to TiO2-NP decreased plasma osmolality and Ca2+ levels. Na+/K+-ATPase, H+-ATPase and carbonic anhydrase activities were inhibited in the gills, but not in the kidney. Total MRC density did not change in gills and kidneys. At gill surface, total MRC density decreased in fish exposed to 50 mg L-1 TiO2-NP and the total MRC fractional surface area unchanged although, there were some changes in the fractional area of MRC with apical microvilli (MRCm) and MRC with apical sponge-like structure (MRCs). MRCm was more abundant than MRCs. After subchronic exposure, there was no change in plasma osmolality, ionic balance and enzyme activities. Total gill MRC density increased in the filament epithelium and renal tubules. In the gills, MRC contacting water exhibited some adjustments. Total MRC and fractional surface area unchanged, but there was an increase of MRCs contacting water at gill surface after exposure to10 and 50 mg L-1 TiO2-NP. MRC proliferation in filament epithelium and in renal tubules as well as the increasing MRCs at gill surface may have contributed to avoid change in plasma osmolality, ionic balance and enzyme activities and suggested a cellular physiological and morphological response to restore and maintain osmotic and ionic homeostasis after subchronic exposure.


Assuntos
Caraciformes/metabolismo , Mitocôndrias/metabolismo , Nanopartículas/toxicidade , Titânio/toxicidade , Clima Tropical , Animais , Anidrases Carbônicas/metabolismo , Brânquias/metabolismo , Brânquias/ultraestrutura , Íons , Rim/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Concentração Osmolar , Tamanho da Partícula , ATPases Translocadoras de Prótons/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Água/química , Poluentes Químicos da Água/toxicidade , Equilíbrio Hidroeletrolítico
20.
Conscientiae saúde (Impr.) ; 15(2): 281-287, 30 jun. 2016.
Artigo em Português | LILACS | ID: biblio-846515

RESUMO

Introdução: A osteoartrose de joelho é caracterizada pela presença de dor. A magnetoterapia é um recurso utilizado para alívio de dor. Objetivo: O objetivo desse estudo foi investigar os efeitos da magnetoterapia no tratamento da dor em pacientes com osteoartrose de joelho. Métodos: Trata-se de uma pesquisa experimental, na qual foram selecionados 2 grupos de 10 voluntários, com diagnóstico clínico de OA. Foram submetidos à 7 semanas de intervenção, G1 associado a um programa de exercícios terapêuticos e G2 com o programa de exercícios associados a magnetoterapia. A avaliação foi realizada através "Western Ontario and McMaster Universities" (WOMAC), do "Timed up and go" (TUG) e da escala analógica (EVA). Resultados: Observou-se que o estudo apresentou diferença estática significativa entre as variáveis *p<0,05 e **p<0,01 para diminuição da dor, rigidez e melhoria da capacidade funcional dos pacientes. Conclusão: A magnetoterapia promove redução da dor e melhora da capacidade funcional de pacientes com osteartrose de joelho.


Introduction: The knee osteoarthritis is characterized by the presence of pain. The magneto therapy is a resource used for pain relief. Objective: The objective of this study was to investigate the effects of magnetic therapy in the treatment of pain in patients with osteoarthritis of the knee. Methods: This is a clinical trial, which were selected two groups of 10 volunteers with a clinical diagnosis of osteoarthristis. They underwent seven weeks of intervention, G1 with a therapeutic exercise program and G2 with the exercise program associated with magnet therapy. The evaluation was conducted by "Western Ontario and McMaster Universities" (WOMAC), the "Timed up and go" (TUG) and analog scale (VAS). Results: It was observed that the study showed significant static difference between the variables * p <0.05 and ** p <0.01 for decrease in pain, stiffness and improving the functional capacity of patients. Conclusion: the magnetic therapy promotes reducing pain and improving functional capacity of patients with osteoarthrosis of knee.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Osteoartrite do Joelho/terapia , Manejo da Dor/métodos , Magnetoterapia , Desempenho Físico Funcional
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...