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1.
Environ Monit Assess ; 194(6): 425, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35552876

RESUMO

We evaluated the environmental quality in mangrove areas of the Western Atlantic with different levels and history of contamination, considering biomarkers for the crab Ucides cordatus. For this purpose, specimens were collected in two climatic seasons (rainy and dry seasons) and assays of genotoxicity (MN, micronucleus), cytotoxicity (NRRT, neutral red retention time) and biochemical (MT, metallothionein; and LPO, lipoperoxidation) were conducted. In the most impacted mangroves, there was an increase in the mean of micronucleus (frequency of MN/1000), which was associated with a shorter retention time (minutes of NRRT). In contrast, the most pristine areas showed MN < 3 and NRRT < 100 min, with no seasonal effect, indicating a lower effect of degenerative processes by xenobiotics. The rainy season was more harmful, especially regarding cytogenotoxicity. The use of bioindicator species for environmental monitoring should be guided by an analysis of biomarkers considering the season, because during the period of highest rainfall, biomarkers values can change.


Assuntos
Braquiúros , Poluentes Químicos da Água , Animais , Biomarcadores/análise , Braquiúros/fisiologia , Monitoramento Ambiental , Estações do Ano , Espécies Sentinelas , Poluentes Químicos da Água/análise
2.
Artigo em Inglês | MEDLINE | ID: mdl-34628057

RESUMO

Cadmium (Cd) can adversely affect aquatic life, altering reproductive and molting processes in crustaceans. The objective of this study was to evaluate the influence of Cd on reproduction and molting in the crab Callinectes danae. Adult females were obtained from environments with different levels of pollution: low (LC), medium (MC), and high contaminated (HC) areas. Animals from LC, MC, and HC areas were exposed to 0, 0.5, and 2 mg L-1 of CdCl2 for 3 h. Cd bioaccumulation, oxidative stress (evaluated by antioxidant enzymes activity), and lipid peroxidation (LPX) were analyzed in mature ovaries (stage II), gills, and hepatopancreas. The expression levels of crustacean hyperglycemic hormone (CHH) and molt-inhibiting hormone (MIH) genes were quantified in the eyestalks, while 17ß-estradiol (E2) and melatonin concentration were measured in the hemolymph. Cd bioaccumulated mainly in the hepatopancreas and gills, with increased E2, LPX, and antioxidant enzymes in HC compared to the LC region. Decreased CHH and MIH transcripts were observed in the animals from HC regions compared to LC and MC areas. Physiological differences were recorded, especially for bioaccumulation, oxidative stress, and hormone levels, in animals sampled in HC areas compared to LC and MC regions. In conclusion, the physiological damage triggered by Cd could be reduced due to higher levels of melatonin and antioxidant enzymes in HC areas.


Assuntos
Cádmio/toxicidade , Crustáceos/metabolismo , Monitoramento Ambiental/métodos , Poluentes Ambientais/toxicidade , Peroxidação de Lipídeos/efeitos dos fármacos , Junção Neuromuscular/efeitos dos fármacos , Animais , Feminino , Neurônios/efeitos dos fármacos
3.
Isotopes Environ Health Stud ; 56(5-6): 431-445, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32930001

RESUMO

Intensive groundwater use has altered the local hydrological cycle within the Bajío Guanajuatense, Mexico. To improve the knowledge of this hydrogeological system and support water management in the area, groundwater end members were identified using multivariate statistical analysis. Pumped groundwater is composed of two well-mixed end members: (a) recent recharge, affected by a reuse cycle through irrigation where nitrate and chloride evolve and reach levels of 368 mg/L and greater than 100 mg/L, respectively, and (b) deep old groundwater. Mixing estimations show that most wells extract at least 70% of deep groundwater, and some of them extract more than 94%, posing a development and groundwater sustainability conundrum in the area.


Assuntos
Deutério/análise , Monitoramento Ambiental/métodos , Água Subterrânea/análise , Isótopos de Oxigênio/análise , Abastecimento de Água/métodos , Cloretos/análise , Água Subterrânea/química , México , Nitratos/análise , Análise Espaço-Temporal , Ciclo Hidrológico , Poços de Água
4.
Environ Sci Pollut Res Int ; 25(35): 35672-35681, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30357663

RESUMO

The field of nanotechnology had enormous developments, resulting in new methods for the controlled synthesis of a wide variety of nanoscale materials with unique properties. Efficient methods such as thermal decomposition for efficient size control have been developed in recent years for the synthesis of oleic acid (OA)-coated magnetite (Fe3O4) nanoparticles (MNP-OA). These nanostructures can be a source of pollution when emitted in the aquatic environment and could be accumulated by vulnerable marine species such as crustaceans. In this work, we synthesized and characterized MNP-OA of three different diameters (5, 8, and 12 nm) by thermal decomposition. These nanoparticles were remarkably stable after treatment with high affinity iron chelators (calcein, fluorescent desferrioxamine, and fluorescent apotransferrin); however, they displayed pro-oxidant activity after being challenged with ascorbate under two physiological buffers. Free or nanoparticle iron displayed low toxicity to four types of hepatopancreatic cells (E, R, F, and B) of the mangrove crab Ucides cordatus; however, they were promptly bioavailable, posing the risk of ecosystem disruption due to the release of excess nutrients.


Assuntos
Braquiúros/efeitos dos fármacos , Hepatopâncreas/efeitos dos fármacos , Nanopartículas de Magnetita , Ácido Oleico/farmacocinética , Animais , Disponibilidade Biológica , Braquiúros/fisiologia , Desferroxamina/metabolismo , Ecossistema , Ecotoxicologia , Fluoresceínas/química , Hepatopâncreas/citologia , Ferro/análise , Ferro/metabolismo , Quelantes de Ferro/química , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/toxicidade , Masculino , Ácido Oleico/química , Tamanho da Partícula , Polissorbatos/química , Transferrina/metabolismo , Áreas Alagadas
5.
Environ Sci Pollut Res Int ; 25(16): 15962-15970, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29589242

RESUMO

The mangrove crab Ucides cordatus is a bioindicator of aquatic contamination. In this work, the iron availability and redox activity of saccharide-coated mineral iron supplements (for both human and veterinary use) and ferrocene derivatives in Saline Ucides Buffer (SUB) medium were assessed. The transport of these metallodrugs by four different hepatopancreatic cell types (embryonic (E), resorptive (R), fibrillar (F), and blister (B)) of U. cordatus were measured. Organic coated iron minerals (iron supplements) were stable against strong chelators (calcein and transferrin). Ascorbic acid efficiently mediated the release of iron only from ferrocene compounds, leading to redox-active species. Ferrous iron and iron supplements were efficient in loading iron to all hepatopancreatic cell types. In contrast, ferrocene derivatives were loaded only in F and B cell types. Acute exposition to the iron compounds resulted in cell viability of 70-95%, and to intracellular iron levels as high as 0.40 µmol L-1 depending upon the compound and the cell line. The easiness that iron from iron metallodrugs was loaded/transported into U. cordatus hepatopancreatic cells reinforces a cautionary approach to the widespread disposal and use of highly bioavailable iron species as far as the long-term environmental welfare is concerned.


Assuntos
Braquiúros/metabolismo , Compostos Ferrosos/metabolismo , Hepatopâncreas/citologia , Ferro/metabolismo , Metalocenos/metabolismo , Poluentes Químicos da Água/análise , Animais , Braquiúros/química , Braquiúros/efeitos dos fármacos , Braquiúros/fisiologia , Compostos Ferrosos/análise , Compostos Ferrosos/química , Hepatopâncreas/efeitos dos fármacos , Humanos , Ferro/análise , Metalocenos/análise , Metalocenos/química
6.
Aquat Toxicol ; 188: 92-99, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28475951

RESUMO

Cadmium is a toxic metal, present in batteries and discarded in estuaries and mangrove habitats. Apart from that, it is a non-essential metal that causes toxic effects in many organisms. Cadmium accumulates in gills and hepatopancreas of crustaceans and its route into the cell is unknown. It is possible that occurs by calcium channels or calcium transporters. The objective of this study was to characterize the transport of cadmium and the role of calcium in different cell types from hepatopancreas of the mangrove crab Ucides cordatus. For this, the hepatopancreas was dissociated by magnetic stirring and after that separated by a sucrose gradient. Then, the cells were labeled with FluoZin-3 AM and different CdCl2 concentrations were added together with a variety of inhibitors. The results showed that Cd2+ transport occurs differently in each cell type from hepatopancreas and is partially explained by the function the cells perform in this organ. Embryonic (E) and Resorptive (R) cells transported more Cd2+ compared to Fibrillar (F) and Blister (B) cells. R cells responded to Ca2+ channel inhibitors and intracellular Ca2+ manipulations positively, as the other cell types and in a stronger way. B cells were the least responsive to Ca2+ channel inhibitors and, unlike the other cells, showed a competition of Cd2+ with intracellular Ca2+ manipulations. The results indicate that Ca2+ affects the transport of Cd2+ in hepatopancreatic cells of Ucides cordatus and uses Ca2+ channels to enter these cells. In addition, information about Ca concentration could be used as a mitigating factor for Cd accumulation in crabs' hepatopancreas.


Assuntos
Braquiúros/metabolismo , Cádmio/farmacocinética , Cálcio/metabolismo , Poluentes Químicos da Água/farmacocinética , Animais , Transporte Biológico , Hepatopâncreas/metabolismo , Masculino , Compostos Policíclicos
7.
Environ Toxicol Chem ; 36(2): 361-371, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27329273

RESUMO

Crustaceans found in metal-contaminated regions are able to survive, and the authors investigated the physiological mechanisms involved by comparing populations from contaminated and noncontaminated areas. The objective of the present study was to measure the cellular transport of a nonessential metal (cadmium [Cd]) in gills and hepatopancreas of Ucides cordatus, together with cell membrane fluidity, metallothionein levels, and lipid peroxidation. The 2 populations compared were from a polluted and a nonpolluted mangrove area of São Paulo State, Brazil. The authors found, for the first time, larger Cd transport in gills and hepatopancreatic cells from crabs living in polluted mangrove areas. The cells also had lower plasma membrane fluidity, increased lipid peroxidation and less metallothionein compared to those from nonpolluted regions. The authors also found larger amounts of Cd in intracellular organelles of gills, but not in the hepatopancreas, from crabs in polluted regions. Therefore, in polluted areas, these animals showed higher Cd transport and lower plasma membrane fluidity and storage of Cd intracellularly in gill cells, whereas hepatopancreatic cells used metallothionein as their main line of defense. The findings suggest that crabs from polluted areas can accumulate Cd more easily than crabs from nonpolluted areas, probably because of an impairment of the regulatory mechanisms of cell membrane transport. Environ Toxicol Chem 2017;36:361-371. © 2016 SETAC.


Assuntos
Braquiúros/efeitos dos fármacos , Cádmio/toxicidade , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/toxicidade , Áreas Alagadas , Animais , Braquiúros/metabolismo , Brasil , Cádmio/metabolismo , Membrana Celular/efeitos dos fármacos , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo , Fluidez de Membrana/efeitos dos fármacos , Metalotioneína/metabolismo , Poluentes Químicos da Água/metabolismo
8.
ImplantNewsPerio ; 1(7): 1417-1421, out.-nov. 2016. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-848043

RESUMO

A hiperplasia fibrosa inflamatória (HFI) é um crescimento gengival que tem como principal causa etiológica o uso de próteses inadequadas ou mal adaptadas. A HFI é uma lesão exofítica benigna de tecido epitelial e conjuntivo fibroso. Seu tratamento de eleição é a exérese cirúrgica e a remoção do agente irritante. Este trabalho teve como objetivo relatar um caso clínico de hiperplasia gengival inflamatória diagnosticada em uma paciente, leucoderma e com 38 anos de idade, que procurou atendimento na Clínica de Periodontia do Sindicato dos Dentistas de Mato Grosso do Sul (Sioms). Após a remoção cirúrgica da lesão e análise histopatológica, o estudo concluiu que o tratamento aplicado neste caso é o mais efetivo para esta patologia, contudo, deve haver avaliações periódicas da prótese para evitar recidiva da lesão.


Inflammatory fibrous hyperplasia (HFI) is a gingival overgrowth that has as its main etiological cause the use of inappropriate or poorly fitting dentures. The HFI is a benign exophytic lesion of epithelial and connective fibrous tissues. The treatment of choice of choice is surgical excision and removal of the irritant. This study aimed to report a clinical case of inflammatory gingival hyperplasia diagnosed in a 38 years-old female patient who sought care in Union Periodontics Clinic of Mato Grosso do Sul Dentists (Sioms). After surgical removal of the lesion and histopathologic analysis the treatment applied in this case is the most effective for this condition, however, periodic reviews must be made to avoid recurrent fibrotic lesions.


Assuntos
Humanos , Feminino , Adulto , Prótese Parcial Removível , Hiperplasia Gengival , Gengivectomia , Mucosa Bucal/lesões
9.
In Vitro Cell Dev Biol Anim ; 47(5-6): 346-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21487924

RESUMO

The gills contain essential cells for respiration and osmoregulation, whereas the hepatopancreas is the site of digestion, absorption, and nutrients storage. The aim of this work was to separate and characterize gill and hepatopancreatic cells of the mangrove crab, Ucides cordatus. For gills, the methodology consisted of an enzymatic cellular dissociation using Trypsin at 0.5%, observation of cellular viability with Tripan Blue, and separation of cells using discontinuous sucrose gradient at concentrations of 10%, 20%, 30%, and 40%. The hepatopancreatic cells were dissociated by magnetic stirring, with posterior separation by sucrose gradient at the same concentrations above. For gills, a high cellular viability was observed (92.5±2.1%), with hemocyte cells in 10% sucrose layer (57.99 ± 0.17%, *P < 0.05), principal cells in the 20% sucrose layer (57.33 ± 0.18, *P < 0.05), and thick cells and pillar cells in the 30% and 40% sucrose layers, respectively (39.54 ± 0.05%, *P < 0.05; and 41.81 ± 0.04%, *P < 0.05). The hepatopancreatic cells also showed good viability (79.22 ± 0.02%), with the observation of embryonic (E) cells in the 10% sucrose layer (67.87 ± 0.06%, **P < 0.001), resorptive (R) and fibrillar (F) cells in the 20% and 30% sucrose layers (44.71 ± 0.06%, **P < 0.001, and 43.25 ± 0.01%, *P < 0.05; respectively), and blister (B) cells in the 40% sucrose layer (63.09 ± 0.03%, **P < 0.001). The results are a starting point for in vitro studies of heavy metal transport in isolated cells of the mangrove crab U. cordatus, subjected to contamination by metals in the mangrove habitat where they are found.


Assuntos
Braquiúros/citologia , Separação Celular/métodos , Brânquias/citologia , Hepatopâncreas/citologia , Animais , Braquiúros/metabolismo , Sobrevivência Celular , Brânquias/metabolismo , Hepatopâncreas/metabolismo , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo , Equilíbrio Hidroeletrolítico
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