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1.
Mar Pollut Bull ; 156: 111232, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32510378

RESUMO

In this study, to better our understanding of the current state of conservation of Cardisoma guanhumi and its habitats, we evaluated the potential spatio-temporal genomic damage of this species across five estuaries in Brazil. The experiment was performed over two consecutive years, and the sampling was performed in the winter and summer seasons. Two genetic tests - micronucleus test and comet assay - were used to quantify the DNA damage. Unlike in the summers and in the winter of 2013, in the winter of 2012 a significant increase was noted in the frequency of micronucleated cells and genomic damage index. The occurrence of genomic damage coincided with the arrival of the harsh winter of 2012 as the water sourced from the coastal rivers significantly affected the estuarine species under study. Our results confirmed that this species was resilient to the atypical climatic conditions, which facilitated the generation of excessive waste.


Assuntos
Braquiúros , Estuários , Animais , Brasil , Ensaio Cometa , Monitoramento Ambiental , Rios , Estações do Ano
2.
Indian J Microbiol ; 60(2): 182-195, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32255851

RESUMO

Prodigiosin is a secondary metabolite, with red pigmentation, produced by Serratia marcescens. Red pigment is a natural alkaloid whose chemical structure has three pyrrole rings. Prodigiosin has been described for several biological activities, including antitumor, inducing apotosis in T and B lymphocytes. This work aimed to evaluate the cytotoxic activity of prodigiosin in NCHI-292, HEp-2, MCF-7 and HL-60 tumor cell lines. The red pigment was isolated from Serratia marcescens UFPEDA 398 biomass whose fractions were previously separated by column chromatography, purified, identified and further characterized by GC-MS and compared with the computerized library of m/z values. The pigment corresponded to prodigiosin with maximum absorption at 534 nm, molecular weight 323 and structural formula C20H25N3O. During the prodigiosin purification process a purple absorbance fraction at 272.65 nm was also observed. Significant cytotoxic effects of prodigiosin were evidenced for NCHI-292, Hep-2, MCF-7 and HL-60 tumor cell lines. The isolated purple fraction had no cytotoxic effect (IC50 11.3 µg/mL) when compared to prodigiosin (IC50 3.4 µg/mL) for the tumor cell lines studied. The MCF-7 strain was slightly more pigment resistant (IC50 5.1 µg/mL). Therefore, further studies will be needed to elucidate the antitumor mechanisms of prodigiosin action against tumor strains from flow cytometry tests. However, although these data are preliminary, it was evidenced that prodigiosin showed cytotoxic activity in tumor cell lines suggesting promising antitumor properties. In this sense, future studies on the cytotoxic and genotoxic effects of prodigiosin produced by S. marcecsens UFPEDA 398 are suggested.

3.
Environ Monit Assess ; 185(10): 8273-85, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23584824

RESUMO

In Brazil, the state of São Paulo contains both preserved areas (Juréia-Itatins Ecological Station) and extremely impacted ones (Cubatão Municipality). This study evaluated the concentrations of five metals (Cu, Cd, Cr, Pb, and Hg) in two mangroves with different levels of anthropogenic impact and the apparent genotoxicity to Ucides cordatus. Water and sediment samples were obtained, and metal concentrations were determined with an atomic absorption spectrophotometer. The genotoxic impact was quantified based on the number of micronucleated cells per 1,000 analyzed (MN‰), using hemolymph slides stained with Giemsa. Metal concentrations in water were below the detection limit, except for lead, although no significant difference was observed between the areas (P > 0.05). Sediment from Cubatão had higher concentrations of Cd, Pb, Cr, and Cu than sediment from Juréia-Itatins (P < 0.05), but no significant differences in metal concentrations were detected among depth strata of the sediment (P > 0.05). Crabs from Cubatão had a 2.6 times higher mean frequency of micronucleated cells (5.2 ± 1.8 MN‰) than those from Juréia-Itatins (2.0 ± 1.0 MN‰; P < 0.0001). The more-polluted conditions found in the mangrove sediments of Cubatão were reflected in the micronucleus assay, demonstrating their genotoxic effect; however, genetic damage should be attributed to a synergistic effect with other kinds of pollutants previously recorded in different environments of Cubatão. U. cordatus proved to be an excellent bioindicator of mangrove pollution. This study established, for the first time, the normal frequency of MN‰ in a population of this species within an ecological station.


Assuntos
Braquiúros/fisiologia , Monitoramento Ambiental , Metais/análise , Poluentes Químicos da Água/análise , Áreas Alagadas , Animais , Brasil , Conservação dos Recursos Naturais/métodos , Ecossistema , Hemolinfa , Metais/toxicidade , Espectrofotometria Atômica , Poluentes Químicos da Água/toxicidade
4.
J Environ Qual ; 33(6): 2165-73, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15537939

RESUMO

Ground water beneath the U.S. Department of Energy Pantex Plant is contaminated with the high explosive RDX (hexahydro-1,3,5-trinitro-1,3,5 triazine). The USDOE Innovative Treatment and Remediation Demonstration (ITRD) program identified in situ oxidation by permanganate as a technology fit for further investigation. We evaluated the efficacy of KMnO(4) to transform and mineralize RDX by determining degradation kinetics and carbon mass balances using (14)C-RDX. Aqueous RDX solutions (2-5 mg L(-1)) and RDX-contaminated slurries (50% solids, w/v) were treated with KMnO(4) at 1000, 2000, 4000, and 20000 mg L(-1). Treating an aqueous RDX solution of 2.8 mg L(-1) with 20000 mg KMnO(4) L(-1) decreased RDX to 0.1 mg L(-1) within 11 d while cumulative mineralization proceeded for 14 d until 87% of the labeled carbon was trapped as (14)CO(2). Similar cumulative mineralization was obtained when Pantex aquifer material was included in the solution matrix. Other experiments using 4000 mg KMnO(4) L(-1) showed that initial RDX concentrations (1.3-10.4 mg L(-1)) or initial pH (4-11) had little effect on reaction rates. Attempts to identify RDX degradates and reaction products showed that N(2)O was a product of permanganate oxidation and constituted 20 to 30% of the N balance. Time-course measurements of a (14)C-RDX solution treated with KMnO(4) revealed few (14)C-labeled degradates but through liquid chromatography-mass spectrometry (LC-MS) analysis, we present evidence that 4-nitro-2,4-diaza-butanol is formed. Aquifer microcosm studies confirmed that the transformation products not mineralized by KMnO(4) were much more biodegradable than parent RDX. These results indicate permanganate can effectively transform and mineralize RDX in the presence of aquifer material and support its use as an in situ chemical oxidation treatment for the Pantex perched aquifer.


Assuntos
Compostos de Manganês/química , Oxidantes/química , Óxidos/química , Poluentes do Solo/isolamento & purificação , Triazinas/química , Triazinas/isolamento & purificação , Poluentes da Água/isolamento & purificação , Purificação da Água/métodos , Biodegradação Ambiental , Oxirredução , Poluentes do Solo/metabolismo , Triazinas/metabolismo , Poluentes da Água/metabolismo
5.
J Orthop Sports Phys Ther ; 18(4): 543-52, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8220413

RESUMO

Advances in isokinetic technology allow the physical therapist to assess concentric, eccentric, and isometric muscle performance at the shoulder in various positions. Research is limited, however, on the reliability of isokinetic measurements. The purposes of this study were: 1) to determine the test-retest reliability of concentric, eccentric, and isometric muscle performance measurements of shoulder external and internal rotation in the scapular plane test position and 2) to compare this reliability between the involved and uninvolved limb of subjects with a history of unilateral shoulder pathology. Fourteen males and 10 females (17-58 years) were tested on two occasions at 1-week intervals with the Biodex isokinetic dynamometer. Peak torque, total work, and average power were recorded for concentric tests at angular velocities of 60 and 120 degrees/sec and for eccentric tests at 60 degrees/sec. Maximum average isometric torque was recorded in two positions. Means, standard deviations, and mean differences between sessions with 95% confidence intervals were calculated. Intraclass correlation coefficients (ICCs) were used to determine test-retest reliability. Isometric tests were generally most reliable (ICC = .81-.93), followed by concentric (ICC = .60-.95) and eccentric tests (ICC = .44-.92). Isokinetic and isometric reliability were usually higher for involved than uninvolved shoulders. The implication of these findings is that there appears to be greater variability with eccentric than concentric or isometric testing of shoulder rotation. Factors that possibly contributed to variability are discussed. Clinicians should recognize potential sources of testing error when obtaining isokinetic measurements for use in clinical decision-making. Further refinement of isokinetic testing protocols at the shoulder is recommended.


Assuntos
Contração Isométrica/fisiologia , Contração Muscular/fisiologia , Ombro/fisiologia , Adolescente , Adulto , Meio Ambiente , Ergometria , Fadiga/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Junção Neuromuscular/fisiologia , Postura , Reprodutibilidade dos Testes , Rotação , Escápula/fisiologia , Trabalho/fisiologia
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