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1.
BMC Ophthalmol ; 23(1): 173, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37095450

RESUMO

AIM: To evaluate association between pretreatment serum metrics and best corrected visual acuity ( BCVA) of patients with macular edema secondary to retinal vein occlusion and its subtypes after intravitreal ranibizumab or conbercept implant. METHODS: This prospective research included 201 patients(201 eyes) who were diagnosed with macular edema secondary to retinal vein occlusion at Heibei Eye Hospital between January 2020 and January 2021, who all received intravitreal anti- vascular endothelial growth factor treatment. Serum metrics were measured before the first treatment, and correlations between BCVA and each of four parameters- platelets, neutrophil- to- lymphocyte ratio(NLR), platelet- to- lymphocyte ratio(PLR) and monocyte- to- lymphocyte ratio(MLR)- were analyzed to identify predictors of effective intravitreal injection treatment outcomes. RESULTS: The mean platelets was significantly different in the effective and ineffective group for RVO-ME (273.02 ± 41.49 × 109/L,214.54 ± 44.08 × 109/L P < 0.01),BRVO-ME (269.43 ± 49.52 × 109/L,214.72 ± 40.42 × 109/L P < 0.01), and CRVO-ME (262.32 ± 32.41 × 109/L,209.27 ± 42 0.91 × 109/L P < 0.01). The cutoff value of the platelets was 266.500, the area under the curve was 0.857,and the sensitivity and specificity were 59.8% and 93.6%, respectively. The mean PLR was significantly different in the effective and ineffective group for RVO-ME (154.66 ± 49.60, 122.77± 44.63 P < 0.01),BRVO-ME (152.24 ± 54.99, 124.72 ± 41.46 P = 0.003), and CRVO-ME (152.06±44.23, 118.67 ± 41.80 P = 0.001). The cutoff value of the platelets was 126.734, the area under the curve was 0.699, and the sensitivity and specificity were 70.7% and 63.3%, respectively. There were no statistical differencies between the effective and ineffective group(RVO- ME and its subtypes) in NLR and MLR. CONCLUSION: Higher pretreatment platelets and PLR were associated with BCVA in patients with RVO- ME and its subtypes who were treated with anti- VEGF drugs. The platelets and PLR may be used as predictive and prognostic tools for effective intravitreal injection treatment outcomes.


Assuntos
Edema Macular , Oclusão da Veia Retiniana , Humanos , Oclusão da Veia Retiniana/tratamento farmacológico , Edema Macular/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular , Dexametasona , Glucocorticoides , Estudos Prospectivos , Tomografia de Coerência Óptica , Resultado do Tratamento , Injeções Intravítreas , Inibidores da Angiogênese/uso terapêutico
2.
Chemosphere ; 300: 134544, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35405199

RESUMO

Selenium (Se) contamination in the soil poses a food safety risk to humans. The present study was to investigate the role of earthworm Eisenia fetida in soil Se remediation. When exposed to selenite at 4 mg Se/kg, E. fetida efficiently concentrated Se in tissues (24.53 mg Se/kg dry weight), however, only accounting for a minor portion of the added Se. Microbial analysis shows 12 out of 15 functional genera became more abundant in the worm-inhabited soil when exposed to Se, suggesting E. fetida contributed to Se remediation mainly by introducing Se-reducing bacteria to the soil via feces, which were dominated by the genera Pseudomonas (∼62.65%) and Aeromonas (∼29.99%), whose abundance was also significantly boosted in the worm-inhabited soil. However, when isolated from worm feces at 200 mg Se/L, Pseudomonas strains only displayed a high tolerance to Se rather than removal capacity. In contrast, among 4 isolated Aeromonas strains, A. caviae rapidly removing 85.74% of the added selenite, mainly through accumulation (67.38%), while A. hydrophila and A. veronii were more effective at volatilizing Se (27.77% and 24.54%, respectively), and A. media performed best by reducing Se by ∼49.00% under anaerobic conditions. Overall, our findings have highlighted the importance of E. fetida as a key contributor of functional bacteria to the soil microbiome, building a strong foundation for the development of an earthworm-soil system for Se bioremediation.


Assuntos
Microbiota , Oligoquetos , Selênio , Poluentes do Solo , Animais , Bactérias , Biodegradação Ambiental , Fezes/química , Ácido Selenioso , Solo , Poluentes do Solo/análise
3.
J Hazard Mater ; 420: 126617, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34271446

RESUMO

With a narrow margin between deficiency and toxicity, rising levels of selenium (Se) are threatening aquatic ecosystems. To investigate the role of microorganisms in Se bioremediation, a cattail litter system inoculated with the sulfur-based denitrification sludge was conducted. The results show the litter, as a carrier and nutrient source for bacteria, efficiently removed Se by ~ 97.0% during a 12-d treatment with water circulating. As the major removal pathways, immobilization rates of selenite were ~ 2.9-fold higher than selenate, and the volatilization, contributing to ~ 87.7% of the total Se removal, was significantly correlated with temperature (positively) and oxidation-reduction potential (ORP; negatively). Using X-ray absorption spectroscopy to speciate litter-borne Se, more Se0 formed without aeration due to abundant Se-reducing bacteria, among which Azospira and Azospirillum were highly related to the removal of both Se oxyanions, while Desulfovibrio, Azoarcus, Sulfurospirillum, Thauera, Geobacter, Clostridium, and Pediococcus were the major contributors to selenate removal. Overall, our study suggests microbial Se metabolism in the litter system was significantly affected by temperature and ORP, which could be manipulated to enhance Se removal efficiency and the transformation of selenate/selenite into low toxic Se0 and volatile Se, reducing risks posed by the residual Se in the system.


Assuntos
Microbiota , Selênio , Typhaceae , Desnitrificação , Esgotos , Enxofre , Temperatura
4.
Chemosphere ; 280: 130593, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33932907

RESUMO

With a narrow margin between beneficial and toxic effects, selenium (Se) is of great concern due to its increasing level in aquatic environments. The accumulation and transformation of Se by the cyanobacterium Microcystis aeruginosa and effects of nutrients, particularly sulfate, were investigated. The nutrient-deprived cyanobacterium removed water-borne selenate (82.2 ± 0.93%) faster than selenite (58.9 ± 1.77%), with 86.0 ± 1.41% and 77.2 ± 1.00%, respectively, of the Se accumulated in the biomass and the rest volatilized. When supplied with excess nutrients, the Se accumulation and volatilization rates were significantly inhibited, with the removal efficiency dropping to 50.2 ± 2.59% and 7.37 ± 0.93% for selenite and selenate, respectively. When M. aeruginosa was tested with inadequate, appropriate, and adequate levels of sulfate, Se uptake decreased with increasing sulfate concentrations, particularly for selenate (from 34.1 to 4.81%). Using X-ray absorption near-edge structure to speciate biomass Se, selenite and selenate were transformed to organo-Se (87.3-100%), with or without nutrients present, suggesting M. aeruginosa could efficiently reduce Se oxyanions to more bioavailable forms. With increasing sulfate levels (5.0 and 10.0 mg S/L), percentages of SeMet converted from selenite decreased by 28.2-33.0%, with 19.1-33.2% as elemental Se, while organo-Se remained dominant (93.6-95.1%) in selenate-treated M. aeruginosa. Transmission electron microscopy shows structural damage in the cell wall at exposure to selenite (1600 µg Se/L), with the intracellular structure intact. To prevent Se biomagnification along aquatic food chains, the Se-laden biomass was combusted as a post-treatment, leading to a significant reduction in Se content (∼99.2%) and Se bioavailability, with inorganic Se (45.0-70.5%) predominant in the residue.


Assuntos
Microcystis , Compostos de Selênio , Selênio , Biomassa , Ácido Selênico , Volatilização
5.
J Hazard Mater ; 405: 124212, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33535361

RESUMO

Selenium (Se)-polluted soils pose serious threats to terrestrial ecosystems through food chains. This study evaluated the use of earthworm Eisenia fetida and organic materials for Se remediation. The greater mortality (6.7%) and weight loss (28.6%) were observed for earthworms exposed to selenate than selenite at 20 mg Se Kg-1 over 21 d, while selenate was taken up 2.5-fold faster than selenite. Compared with peat moss, Se accumulation increased by 119% in selenite-exposed earthworms supplied with cow manure. Earthworm activity caused greater reduction in selenite (17.4%), with little impact on selenate-treated soil. X-ray absorption spectroscopy speciation analysis shows 87-91% of tissue Se was transformed to organo-Se, i.e., SeMet and SeCys, in earthworms exposed to either selenite or selenate, posing great risks to their predators. The study also found selenium increased bacterial diversity in earthworm casts, while greater relative abundances (~37.57%) of functional genera were obtained for selenite. Over 24 h, two bacteria strains, Bacillus cereus and Aeromonas encheleia, isolated from casts, rapidly reduced selenite by ~94%, compared to ~25% for selenate. Elemental Se was present only in strains (~27%), casts (~11%) and worm-inhabited soil (~2.7%) of selenite treatments, suggesting earthworm gut microbiota could buffer earthworms and other soil fauna from selenite toxicity.


Assuntos
Oligoquetos , Selênio , Aeromonas , Animais , Bovinos , Ecossistema , Feminino , Selênio/toxicidade , Solo
6.
Sci Total Environ ; 742: 140661, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32721753

RESUMO

Increasing selenium (Se) levels in aquatic environments raise concerns all over the world. This study investigated effects of organic amendments (cattail and reed litter) and porous media (gravels and clam shells) on Se removal efficiency of horizontal subsurface flow constructed wetlands. Our results show clam shells reduced Se (by mass) up to 2.4-fold faster than gravels within 19 days. Using clam shells as the sole substrate, 96.3% removal efficiency was obtained for cattail litter as an amendment, compared to 88.7% for reed litter over 10 days, although the latter released carbon and nitrogen at least 1.4-fold faster than the former. Meanwhile, speciation analysis suggests Se0 (~75%) and organo-Se (~94%) dominated the biofilms on shells and plant litter, respectively, as substrates. Overall, this study suggests clam shells and cattail litter as an effective medium and carbon source, respectively, can enhance microbial Se removal without posing risks to wildlife health.


Assuntos
Bivalves , Selênio , Typhaceae , Animais , Carbono , Nitrogênio , Áreas Alagadas
7.
Sci Total Environ ; 724: 138219, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32251888

RESUMO

The release of selenium (Se) and chromium (Cr) into the environment from anthropogenic activities has posed a hazard to aquatic ecosystems. In this study, we used Chlorella vulgaris for Se/Cr bioremediation and evaluated their mutual effects on the removal efficiency. Our results found C. vulgaris highly effective in removing selenite-Se(IV) (49.5 ± 1.9%), selenate-Se(VI) (93.0 ± 0.5%), chromic nitrate-Cr(III) (89.0 ± 3.2%) and dichromate-Cr(VI) (88.1 ± 1.3%) over a 72 h period. Cr(VI) significantly impeded Se removal, particularly for selenate, due to competition between both for algal uptake, whereas Cr(III) obviously enhanced Se removal, increasing Se volatilization by ~29%. Similarly, Se significantly increase Cr removal rates, with a maximum of 94.6 ± 0.2% for the algal co-exposed to Se(IV) and Cr(III). To reduce residual pollutants in the alga, we applied combustion as a post-treatment to burn off >99% of the biomass Se for all Se treatments, whereas most of the biomass Cr (54.7-81.6%) remained in the ash at significantly higher levels (~7430 µg Cr/g DW). For toxicity, our speciation analysis found organo-Se (SeCys and SeMet) dominant in the alga exposed to Se, particularly selenite. No Cr(VI) but Cr(III) forms were detected in all Cr-exposed alga. Elemental Se disappeared from all Se-exposed alga in the presence of Cr(VI), while Se resulted in the emergence of Cr-acetate in all Cr(III)-treated alga. After combustion, mineral Se, particularly elemental Se dominated most of the ash; likewise, elemental Cr, along with Cr2O3, was found in all the ash. Overall, our research would contribute to developing a low ecotoxic algal treatment system for Se/Cr contaminated water.


Assuntos
Chlorella vulgaris , Selênio , Poluentes Químicos da Água/análise , Cromo , Ecossistema
8.
Environ Pollut ; 262: 114288, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32155550

RESUMO

As an essential micronutrient for animals with a narrow range between essentiality and toxicity, selenium (Se) usually coexists with chromium (Cr) in contaminated aquatic environments. This study investigated effects of three diets (Microcystis aeruginosa, Chlorella vulgaris and biofilms) exposed to Se or/and Cr on Aedes albopictus as a vector for the aquatic-terrestrial transfer of Se and Cr. Se(IV)-exposed mosquitoes concentrated Se up to 66-fold faster than Se(VI)-exposed ones, corresponding to the greater Se enrichment in Se(IV)-treated diets. Analysis using synchrotron-based X-ray absorption spectroscopy (XAS) showed that Se(0) (61.9-74.6%) dominated Se(VI)-exposed mosquitoes except for the C. vulgaris-fed larvae (organo-Se, 94.0%), while organo-Se accounted for 93.3-100.0% in Se(IV)-exposed mosquitoes. Cr accumulation in larvae (56.40-87.24 µg Cr/g DW) or adults (19.41-50.77 µg Cr/g DW) was not significantly different among all Cr(VI) treatments, despite varying diet Cr levels. With Cr(0) being dominant (57.7-94.0%), Cr(VI)-exposed mosquitoes posed little threat to predators. Although mosquitoes exposed to Se or Cr had shorter wings, adults supplied with C. vulgaris or biofilms co-exposed to Se(VI) and Cr(VI) had wings significantly (1.1-1.2 fold) longer than Se(VI) only exposed ones. Overall, our study reveals the role of Ae. albopictus in transferring waterborne Se and Cr from the contaminated aquatic ecosystem to the terrestrial ecosystem with the resulting eco-risks to wildlife in both ecosystems.


Assuntos
Aedes , Chlorella vulgaris , Selênio , Animais , Biotransformação , Cromo , Ecossistema , Mosquitos Vetores
9.
Environ Pollut ; 245: 941-949, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30682750

RESUMO

Selenium (Se) is an essential micronutrient for animals with a relatively narrow margin between essentiality and toxicity. To evaluate Se removal efficiency by a constructed wetland treatment system and its potential eco-risk, a floating-leaved macrophyte system was constructed, consisting of three main trophic levels. Over 21-d treatment, water Se concentration was gradually reduced by 40.40%, while 24.03% and 74.41% of the removed Se were found in the plant Nymphoides sp. and sediment, respectively. Among plant tissues, roots accumulated the highest Se level, although the greatest total Se was found in stems, followed by leaves, roots and rhizomes. X-ray absorption spectroscopy revealed that 82.65% of the absorbed selenite by the plants was biotransformed to other forms, as organo-Se species accounted for 45.38% of the Se retained in the sediment, which was primarily responsible for the entry of Se into the detritus food chain. The proportion of organo-Se compounds increased with trophic levels from sediments to fish, indicating, instead of direct uptake of selenite, the food chain transfer and biotransformation of Se may serve as a key exposure route for Se in aquatic organisms. When exposed to organo-Se compounds, i.e., SeCys and SeMet, the plants, shrimp and fish tended to accumulate more Se. However, the greater trophic transfer factor was obtained for selenate, leading to higher Se levels accumulated in fish. Overall, in addition to key mechanisms involved in Se removal, our research also provides a much better understanding of the potential eco-risk that may be posed by the floating-leaved plant system for bioremediation of Se via food chain transfer and biotransformation, paving the way for a low eco-toxic treatment system for Se remediation.


Assuntos
Asteraceae/crescimento & desenvolvimento , Sedimentos Geológicos/química , Selênio/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Áreas Alagadas , Animais , Asteraceae/metabolismo , Biodegradação Ambiental , Biotransformação , China , Peixes/metabolismo , Cadeia Alimentar , Sedimentos Geológicos/microbiologia , Modelos Teóricos , Selênio/metabolismo , Caramujos/metabolismo , Poluentes Químicos da Água/metabolismo
10.
J Hazard Mater ; 365: 546-554, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30469034

RESUMO

In developing an algal treatment system, selenium (Se) removal efficiency by Chlorella vulgaris was evaluated under various conditions such as Se concentration, algal density, temperature and pH. A maximum removal efficiency plateau of ∼90% was observed between 1000-3000 µg Se/L while the tolerance of Se toxicity was found at 6000 µg Se/L. C. vulgaris of 0.75 g DW/L showed the highest removal efficiency (84%), and volatilization was dominant below 1.37 g DW/L. Se volatilization was two times higher at 25 °C than at 20 °C in the first 24 h. Moreover, the highest removal efficiency (77%) was obtained at pH 8.0, compared to 66.5% at pH 6.5 and 40% at pH 10.0. To prevent ecotoxicity, Se laden algae were further burned to ashes or filtered out by Anodonta woodiana. After burning, biomass Se was reduced by 99%, with organo-Se entirely converted into inorganic Se, lowering Se bioavailability. A. woodiana removed 54% of Se in 24 h, leading to Se bioaccumulation in soft tissues, which may serve as dietary Se supplements for human health. Our results suggest the cleanup of Se-contaminated water from either agricultural runoff or industrial discharge could be achieved using an algal treatment system with minimum potential ecotoxicity.


Assuntos
Alga Marinha/metabolismo , Selênio/isolamento & purificação , Selênio/metabolismo , Poluentes Químicos da Água/isolamento & purificação , Biomassa , Biotransformação , Concentração de Íons de Hidrogênio , Temperatura
11.
Chemosphere ; 217: 825-832, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30458418

RESUMO

In our previous studies, Chlorella vulgaris had proven highly efficient in removing selenium (Se) from water, while the disposal of Se containing in algal biomass was still an issue of concern. Firstly, this research suggests algal Se could be released back to water, posing risks to aquatic wildlife. Thus, we further explored the possibility of using C. vulgaris to remove Se and produce lipid and hydrogen simultaneously. Our results show the higher percentage of saturated fatty acids, especially palmitic acid, was found in the sulfur (S) deprived algae exposed to either selenate or selenite, although the highest lipid content (21.9%) was found in the selenite treated algae in full BG11 medium. In addition, compared with the Se free algae, hydrogen production rate was 2.1- and 4.3-fold higher for the selenate and selenite treated algae, respectively. Se removal efficiency achieved by the selenite treated algae through accumulation and volatilization was 2.3-fold higher than the selenate treatment under hypoxic condition with S deprived, which is in contrast to the results obtained under aerobic conditions.


Assuntos
Chlorella vulgaris/metabolismo , Hidrogênio/metabolismo , Lipídeos/biossíntese , Selênio/farmacocinética , Biomassa , Ácido Selênico/farmacologia , Ácido Selenioso/farmacologia , Enxofre , Volatilização , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/metabolismo
12.
Environ Pollut ; 242(Pt A): 73-81, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29960927

RESUMO

Selenium (Se) is an essential micronutrient for animals and humans with a relatively narrow margin between nutritional essentiality and potential toxicity. Even though our previous studies have demonstrated algae could efficiently remove Se, mainly through volatilization, concern is raised about eco-risks posed by the remaining Se in algae. Here, Sinanodonta woodiana was investigated as a biofilter for the removal of Se-containing Chlorella vulgaris and for its potential risk to human health. Our results suggest filtration rates of S. woodiana were independent of Se levels in algal biomass, with a removal efficiency of between 60 and 78%. However, Se concentrations accumulated in mussels were significantly correlated with algal-borne Se levels, with a dietary assimilation efficiency ranging from 12% to 46%. Thus, a pilot biofiltration system was set up to assess uptake and depuration processes. The system was found to efficiently remove Se laden algae through the uptake by mussels, while 21% of Se in mussels could be depurated in 6 days. Among tissues, gills accumulated the highest Se concentration after assimilating algal-borne Se but shed Se compounds in the fastest pace during depuration. Health risks posed by consumption of mussels exposed to different sources of Se were further assessed. S. woodiana accumulated the highest Se concentration after exposure to waterborne SeMet, followed by dietary Se, selenite and control. The relatively higher Se levels were found in gills for all the treatments. After boiling, the most common method of cooking mussels, the greatest reduction in Se concentration occurred in mantle for the control and dietary Se groups and in muscle for the SeMet and selenite treatments. Therefore, within the safe limits, Se-containing mussels can be consumed as a dietary supplement. Overall, our research suggests incorporation of mussels into an algal treatment system can improve Se removal efficiency and also provide financial incentives for practitioners.


Assuntos
Chlorella vulgaris/metabolismo , Contaminação de Alimentos/análise , Selênio/metabolismo , Unionidae/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Monitoramento Ambiental , Cadeia Alimentar , Brânquias/metabolismo , Humanos , Medição de Risco
13.
Int J Anal Chem ; 2017: 1693464, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28567056

RESUMO

Benzoylpaeoniflorin (BP) is a potential therapeutic agent against oxidative stress related Alzheimer's disease. In this study, a more rapid, selective, and sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed to determine BP in rat plasma distinguishing with a monoterpene isomer, benzoylalbiflorin (BA). The method showed a linear response from 1 to 1000 ng/mL (r > 0.9950). The precision of the interday and intraday ranged from 2.03 to 12.48% and the accuracy values ranged from -8.00 to 10.33%. Each running of the method could be finished in 4 minutes. The LC-MS/MS method was validated for specificity, linearity, precision, accuracy, recovery, and stability and was found to be acceptable for bioanalytical application. Finally, this fully validated method was successfully applied to a pharmacokinetic study in rats following oral administration.

14.
Environ Pollut ; 223: 535-544, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28129951

RESUMO

Se laden freshwater algae that enter the Salton Sea with river water pose ecorisks to wildlife in the lake by transferring selenium (Se) to higher trophic levels. The aim of this study was to investigate impacts of Se on Microcystis aeruginosa, widely distributed in freshwater bodies, and its relationship with toxicity, such as microcystins and Se residues. When supplied with selenite, the 96 h-IC50 was calculated 2.60 mg Se/L. However, these inhibitory effects did not extend to microcystin production, and the extracellular fraction significantly increased with selenite as well as sulfate. As M. aeruginosa assimilated selenite very efficiently, 97% of the removed Se was through accumulation, compared to 3% via volatilization, raising a concern about ecotoxicity caused by the remaining Se in the algae. The XAS analysis suggests the dominant Se species accumulated in the algal cells was elemental Se (81%), which is relatively nonbioavailable to aquatic organisms. We further investigated the potential fate of Se carried into the Salton Sea by M. aeruginosa with river water. Under hypersalinity stress, the biomass Se and intracellular microcystins were released and reduced by 47% and 74%, respectively, resulting in the increasing levels of Se and microcystins in the water column. CuSO4 was then applied as an algaecide to prevent M. aeruginosa from entering the lake. The results indicate a similar response to that under hypersalinity stress: the volatilization process was blocked and the Se and microcystins were released from the damaged algal cells in the presence of CuSO4, further raising toxicity levels by 8% and 60%, respectively, in the water column within 24 h. Overall, the coexistence of selenite and M. aeruginosa in river waters might negatively impact aquatic ecosystems of the Salton Sea and further research is required on how to harvest Se from M. aeruginosa to protect local wildlife.


Assuntos
Microcystis/efeitos dos fármacos , Ácido Selenioso/toxicidade , Sulfato de Cobre/farmacologia , Herbicidas/toxicidade , Lagos , Microcistinas/biossíntese , Microcystis/crescimento & desenvolvimento , Microcystis/metabolismo , Salinidade , Sulfatos/farmacologia
15.
Chemosphere ; 164: 372-378, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27596824

RESUMO

Selenium (Se) exposure poses potential risks to wildlife at the Salton Sea. Our previous research suggests Chlorella sp. be highly efficient at absorbing and volatilizing Se. In developing an algal treatment system for Se removal, this study further evaluated the performance under the conditions to be encountered in the field using Chlorella pyrenoidosa and Chlorella vulgaris. The results show the algal Se removal efficiency was little affected by photoperiod, yet volatilization became relatively greater in dark/light cycles over a longer term. The rates of Se absorption and volatilization by C. vulgaris were 88% and 77% more, respectively, in the DI water, while C. pyrenoidosa acted oppositely, indicating C. vulgaris will perform better in Se removal if nutrient levels are reduced in advance. The presence of sulfate reduced biomass Se, especially through volatilization, by 8% for C. vulgaris, lessening potential ecotoxicity. Finally, C. vulgaris released biomass Se back to the water column under hypersaline conditions, leading to a 6% increase in water Se concentrations. These results suggest C. vulgaris be the best alga for the treatment of Se laden river water in the Salton Sea area, yet a filtering system is required to prevent Se containing algae from entering food chains.


Assuntos
Chlorella vulgaris/metabolismo , Alimentos/efeitos adversos , Fotoperíodo , Salinidade , Compostos de Selênio/isolamento & purificação , Sulfatos/farmacologia , Poluentes Químicos da Água/isolamento & purificação , Biodegradação Ambiental , Biomassa , Chlorella vulgaris/efeitos dos fármacos , Chlorella vulgaris/crescimento & desenvolvimento , Humanos , Compostos de Selênio/metabolismo , Volatilização , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos
16.
Ecotoxicology ; 25(7): 1318-26, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27315091

RESUMO

Multixenobiotic resistance (MXR) transporters, which belong to ATP-binding cassette (ABC) family proteins, are present in living organisms as a first line of defense system against xenobiotics and environmental contaminants. The effects of six organic UV filters (4-methyl -benzylidene camphor, 4-MBC; benzophenone-3, BP-3; butyl methoxydibenzoyl-methane, BM-DBM; ethylhexyl methoxy cinnamate, EHMC; octocrylene, OC and homosalate, HMS) on multixenobiotic resistance (MXR) in Tetrahymena thermophila were investigated in this study. It was found that 4-MBC, BP-3 and BM-DBM could significantly inhibit activity of the MXR system, causing concentration dependent accumulation of rhodamine 123; while EHMC, OC and HMS had weak MXR inhibition. The IC50 (50 % inhibition concentration) values of 4-MBC, BP-3 and BM-DBM were 23.54, 40.59 and 26.37 µM, respectively, with inhibitory potentials of 23.1, 13.4 and 20.6 % relative to verapamil (VER, a model inhibitor of P-glycoprotein). Our results firstly provide the evidence for UV filters inhibition effect on MXR in aquatic organisms. In addition, it was revealed by molecular docking analysis that the selected six UV filters can occupy the same binding site on T. thermophila P-gp as VER does; and form H-bonds with residues Ser 328 and/or Asn 281. This study raises the awareness of aquatic ecological risk from the organic UV filters exposure, as they would be involved in potentiating toxic effects by chemosensitizing.


Assuntos
Resistência a Medicamentos/efeitos dos fármacos , Rodamina 123/metabolismo , Protetores Solares/toxicidade , Tetrahymena thermophila/fisiologia , Poluentes Químicos da Água/toxicidade , Subfamília B de Transportador de Cassetes de Ligação de ATP , Bioensaio , Simulação de Acoplamento Molecular
17.
Chemosphere ; 139: 434-40, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26246462

RESUMO

The information about adverse effects of emerging contaminants on aquatic protozoa is very scarce. The growth inhibition effect, cell viability, genotoxicity and multixenobiotic resistance (MXR) responses of two commonly used antimicrobial agents, triclosan (TCS) and triclocarban (TCC) to protozoan Tetrahymena thermophila were investigated in this study. The results revealed that TCS and TCC can inhibit the growth of T. thermophila with 24h EC50 values of 1063 and 295µgL(-1), respectively. The impairment of plasma membrane was observed after 2h exposure of TCS or TCC at the level of mg/L. Furthermore, it is noticeable that at environmentally relevant concentration (1.0µgL(-1)), both TCS and TCC can lead to statistically significant DNA damage in T. thermophila, while the inhibition of growth and change of cell viability cannot be observed. Our results firstly provide the evidence for genotoxic effects of TCS and TCC on the freshwater protozoan. Additionally, both TCS and TCC were found to inhibit the efflux transporter activities, with the inhibitory potencies of 39% and 40% (using verapamil as a model inhibitor), respectively. Particularly, TCC could significantly down-regulate the expression of MXR related gene Abcb15, which encodes the membrane efflux protein that acting as P-gp in T. thermophila. The results raise the awareness of potential aquatic ecological and human health risks from the exposure of TCS and TCC, as they might potentiate the toxic effects by chemosensitizing with co-existing toxicants.


Assuntos
Carbanilidas/toxicidade , Resistência a Medicamentos/efeitos dos fármacos , Tetrahymena thermophila/citologia , Tetrahymena thermophila/genética , Triclosan/toxicidade , Xenobióticos/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 , Sobrevivência Celular/efeitos dos fármacos , Interações Medicamentosas , Monitoramento Ambiental/métodos , Água Doce/química , Mutagênicos/toxicidade , Tetrahymena thermophila/efeitos dos fármacos , Tetrahymena thermophila/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade , Xenobióticos/metabolismo
18.
Bioorg Med Chem Lett ; 24(2): 586-90, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24370011

RESUMO

A novel series of 4-pyrazolyl-1,8-naphthalimide derivatives have been designed and facilely synthesized. For anticancer activity in vitro, most of the compounds were found to be more toxic against human mammary cancer cells (MCF-7) than human cervical carcinoma cells (Hela) and human lung cancer cells (A549). Compounds 4i, 4h, 4b and 4a showed improved cytotoxic activity against MCF-7 cells over amonafide, in particular compounds 4i and 4h, the IC50 values of which against cell lines of MCF-7 were 0.51 µM and 0.79 µM, respectively. The DNA-binding properties of 4i were investigated by UV-vis, fluorescence, and Circular Dichroism (CD) spectroscopies and thermal denaturation. The results indicated that compound 4i as the DNA-intercalating agent exhibited middle binding affinity with CT-DNA.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/metabolismo , DNA/metabolismo , Naftalimidas/síntese química , Naftalimidas/metabolismo , Animais , Bovinos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Células HeLa , Humanos , Substâncias Intercalantes/síntese química , Substâncias Intercalantes/metabolismo , Células MCF-7 , Ligação Proteica/fisiologia , Relação Estrutura-Atividade
19.
Chemosphere ; 93(10): 2507-13, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24129001

RESUMO

UV filters are increasingly used in sunscreens and other personal care products. Although their residues have been widely identified in aquatic environment, little is known about the influences of UV filters to protozoan. The growth inhibition effects, cell viability and oxidative stress responses of four commonly used UV filters, 2-ethylhexyl 4-methoxycinnamate (EHMC), benzophenone-3 (BP-3), 4-methyl-benzylidene camphor (4-MBC) and octocrylene (OC), to protozoan Tetrahymena thermophila were investigated in this study. The 24-h EC50 values with 95% confidence intervals for BP-3 and 4-MBC were 7.544 (6.561-8.675) mg L(-1) and 5.125 (4.874-5.388) mg L(-1), respectively. EHMC and OC did not inhibit the growth of T. thermophila after 24h exposure at the tested concentrations. The results of cell viability assays with propidium iodide (PI) staining were consistent with that of the growth inhibition tests. As for BP-3 and 4-MBC, the relatively higher concentrations, i.e. of 10.0 and 15.0 mg L(-1), could lead to the cell membranes impairment after 4h exposure. With the increase of the exposure time to 6h, their adverse effects on cell viability of T. thermophila were observed at the relatively lower concentration groups (1.0 mg L(-1) and 5.0 mg L(-1)). In addition, it is noticeable that at environmentally relevant concentration (1.0 µg L(-1)), BP-3 and 4-MBC could lead to the significant increase of catalase (CAT) activities of the T. thermophila cells. Especially for the BP-3, the oxidative injuries were further confirmed by the reduction of glutathione (GSH) content. It is imperative to further investigate the additive action of UV filters and seek other sensitive endpoint, especially at environmentally relevant concentration.


Assuntos
Estresse Oxidativo , Protetores Solares/toxicidade , Tetrahymena thermophila/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Acrilatos/toxicidade , Benzofenonas/toxicidade , Cânfora/análogos & derivados , Cânfora/toxicidade , Sobrevivência Celular , Cinamatos/toxicidade , Tetrahymena thermophila/fisiologia , Raios Ultravioleta
20.
Bioorg Med Chem Lett ; 23(18): 5187-91, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23927970

RESUMO

Pd(II), Cu(II) and Zn(II) complexes (1-3) based on 4'-(4-(2-(piperidin-1-yl)ethoxy)phenyl)-2,2':6',2″-terpyridine were synthesized and characterized by UV, IR, NMR, EPR, HRMS, elemental analyses, and molar conductivity measurements. The cytotoxicity of these complexes against HL-60, BGC-823, KB, Bel-7402, A549, Hela, K562 and MCF-7 cell lines in vitro was measured by MTT method. The DNA binding property of the complexes was evaluated by UV, fluorescence, CD spectroscopies and thermal denaturation. The cytotoxicity of complexes 1 and 3 against all the tested cell lines is better than that of cisplatin. Complexes 1 and 2 exhibit 7- and 4-folds higher cytotoxicity than cisplatin against Bel-7402 cell line. Complex 3 displays the highest cytotoxicity against all the cell lines tested, and shows 7-, 14-, 8-, 11- and 8-folds higher cytotoxicity than cisplatin against Bel-7402, A549, Hela, K562 and MCF-7 cell lines. The complexes bind to DNA via intercalation mode and complex 3 stabilizes the G-quadruplex. The results reveal that all the complexes display high cytotoxicity against all the tested cancer cell lines, and complex 3 is selective for G-quadruplex over duplex DNA.


Assuntos
Antineoplásicos/farmacologia , Cobre/química , DNA de Neoplasias/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Paládio/química , Piperidinas/química , Piridinas/química , Zinco/química , Antineoplásicos/síntese química , Antineoplásicos/química , Sítios de Ligação/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA de Neoplasias/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Células HeLa , Humanos , Células K562 , Células KB , Células MCF-7 , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Relação Estrutura-Atividade
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