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1.
Ecotoxicol Environ Saf ; 282: 116760, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39029223

RESUMO

The study on the influence of Natural Organic Matter (NOM) over the individual and combined effects of different nanomaterials on marine species is pertinent. The current study explores the role of Extracellular Polymeric Substances (EPS) in influencing the individual and combined toxic effects of polystyrene nanoplastics (PSNPs) viz. aminated (NH2-PSNPs), carboxylated (COOH-PSNPs), and plain PSNPs and TiO2 NPs in the marine crustacean, Artemia salina. A. salina was interacted with pristine PSNPs, pristine TiO2 NPs, EPS incubated PSNPs, EPS incubated TiO2 NPs, binary mixture of PSNPs and TiO2 NPs, and EPS adsorbed binary mixture of PSNPs and TiO2 NPs for 48 h. The present study proves that, when compared to the pristine toxicity of PSNPs and TiO2 NPs, the coexposure of TiO2 NPs with PSNPs resulted in increased toxicity. The adsorption of algal EPS on the NMs (both in their pristine and combined forms) significantly increased the toxic nature of the NMs against A. salina. It was observed that with an increase in the hydrodynamic diameter of the particles, the mortality, oxidative stress, and ingestion of the NMs by A. salina increased. The uptake of Ti by A. salina from 8 mg/L TiO2 NPs, EPS adsorbed 8 mg/L TiO2 NPs, 8 mg/L TiO2 NPs + NH2-PSNPs and the EPS adsorbed mixture of 8 mg/L TiO2 NPs, 8 mg/L TiO2 NPs + NH2-PSNPs was observed to be 0.043, 0.047, 0.186, and 0.307 mg/g of A. salina. The adsorption of algal EPS on the NMs (both in their pristine and combined forms) significantly increased the toxic nature of the NMs against A. salina. The major outcomes from the current study highlight the role of EPS in exacerbating the toxicity of NMs in marine crustaceans.


Assuntos
Artemia , Poliestirenos , Titânio , Poluentes Químicos da Água , Animais , Artemia/efeitos dos fármacos , Titânio/toxicidade , Poliestirenos/toxicidade , Poluentes Químicos da Água/toxicidade , Matriz Extracelular de Substâncias Poliméricas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Nanopartículas/toxicidade , Adsorção , Microplásticos/toxicidade
2.
Ecotoxicol Environ Saf ; 280: 116542, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38850698

RESUMO

The use of disposable face masks (DFMs) increased during the COVID-19 pandemic and has become a threat to the environment due to the release of microplastics (MPs). Although many reports have characterized and explored the release of MPs from DFMs and their effects in aquatic ecosystems, there is a lack of investigation into the effects in terrestrial plants. This report aims to fill this research gap by characterizing whole mask leachates (WMLs) collected at different time points and examining their toxicity on Allium cepa, a terrestrial model plant. Various analytical techniques including FE-SEM, FT-IR, and Raman spectroscopy were used to identify MPs in WMLs. The MPs are composed of polypropylene mostly and the concentration of smaller-sized MPs increased with leachate release time. The WMLs showed a MP concentration-dependent cytogenotoxic effect (72 %, 50 %, and 31 %, on 1, 5, and 11-day WMLs, respectively) on A. cepa root cells due to elevated oxidative stress (19 %, 45 %, and 70 %, on 1, 5, and 11-day WMLs, respectively). Heavy metal content of the WMLs was negligible and, thus, not a significant contributor to toxicity in the plant. Overall, this report highlights the fate of DFMs in the environment and their biological impacts in a model plant.


Assuntos
Máscaras , Microplásticos , Cebolas , Cebolas/efeitos dos fármacos , Microplásticos/toxicidade , COVID-19 , Estresse Oxidativo/efeitos dos fármacos , Fatores de Tempo , Metais Pesados/análise , Metais Pesados/toxicidade , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Raízes de Plantas
3.
Mol Cell Biochem ; 478(12): 2609-2620, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36894690

RESUMO

Aeromonas hydrophila is a fish pathogen which is widely associated with diseases related to freshwater fishes. Vibrio parahemolyticus is a major globally emerging marine pathogen. Seven novel compounds were extracted from the ethyl acetate extract of Bacillus licheniformis, a novel marine bacterium isolated from marine actinomycetes. The compounds were identified using Gas Chromatography-Mass Spectroscopy (GC-MS). Only one bioactive compound having potent antibacterial activity was virtually screened to understand its drug-like property according to Lipinski's rule. The core proteins, 3L6E and 3RYL from the pathogens, A. hydrophila and V. parahemolyticus were targeted for drug discovery. In the present in-silico approach, Phenol,2,4-Bis(1,1-Dimethylethyl) a potent bioactive compound present in Bacillus licheniformis was used to prevent the infection due to the two pathogens. Further, using this bioactive compound, molecular docking was done to block their specific target proteins. This bioactive compound satisfied all the five rules of Lipinski. Molecular docking result revealed the best binding efficacy of Phenol,2,4-Bis(1,1-Dimethylethyl) against 3L6E and 3RYL with - 4.24 kcal/mol and - 4.82 kcal/mol, respectively. Molecular dynamics (MD) simulations were also executed to determine the binding modes as well as the stability of the protein-ligand docking complexes in the dynamic structure. The in vitro toxicity analysis of this potent bioactive compound against Artemia salina was carried out, revealing the non-toxic nature of B. licheniformis ethyl acetate extract. Thus, the bioactive compound of B. licheniformis was found to be a potent antibacterial agent against A. hydrophila and V. parahemolyticus.


Assuntos
Bacillus licheniformis , Infecções Bacterianas , Animais , Simulação de Acoplamento Molecular , Antibacterianos/farmacologia , Antibacterianos/química , Peixes , Fenóis
4.
Stat Med ; 41(16): 2978-3002, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35403240

RESUMO

We propose a test for multisample comparison studies that can be applied without strict assumptions, especially when the underlying population distributions are far from normal. The new test can detect differences not only in location or scale but also in shape parameters among parent population distributions. We are motivated by numerous medical studies, where the variables are not normally distributed and may present in the various groups more complex differences than simple differences in a particular aspect of underlying distributions, such as location or scale. In these situations, traditional ANOVA and Kruskal-Wallis tests are unreliable since the underlying assumptions are not valid. The proposed procedure also allows the researcher to determine which aspects are more responsible for a significant result. This is an important practical advantage over procedures that test for general differences among the distribution functions but cannot identify which aspects lead to significant results. The asymptotic distribution of the test statistic is analyzed along with its small sample behavior against several competing tests. The practical advantages of the proposed procedure are illustrated with a multisample comparison study of a biomarker for liver damage in patients with hepatitis C.


Assuntos
Estatísticas não Paramétricas , Interpretação Estatística de Dados , Humanos
5.
Environ Res ; 204(Pt D): 112400, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34800532

RESUMO

Widespread usage of nano-TiO2 in various commercial products and their consequent release into the seawater pose a severe threat to marine biota. Nanoplastics, a secondary pollutant in the marine environment, could influence adverse effects of nano-TiO2. The main goal of the present study was to investigate the influence of the differently functionalized polystyrene nanoplastics (COOH-PSNPs, NH2-PSNPs, and Plain-PSNPs) on the acute toxic effects of P25 nano-TiO2 in marine algae Chlorella sp. Three different concentrations of nano-TiO2, 0.25, 0.5, and 1 mg/L, mixed with 5 mg/L of the PSNPs were employed in this study. A substantial increase was noted in mean hydrodynamic sizes of nano-TiO2 when they were mixed with the PSNPs. This hetero-aggregation would reduce the bioavailability of the particles to the algae. The presence of the PSNPs in the mixture reduced the toxicity of nano-TiO2 significantly. A signficant decline in the oxidative stress parameters like total ROS, superoxide (), and hydroxyl radical generation was noted for the mixture of nano-TiO2 with the PSNPs in comparison with the pristine counterparts. The lipid peroxidation, and the antioxidant enzyme activities in the cells correlated well with the reactive species generation results. The treatments with the mixture resulted in notable enhancement in the esterase activity in the cells. The Independent Action model suggested antagonistic interactions between PSNPs and nano-TiO2. The results from this study clearly demonstrate that nano-TiO2 in presence of the PSNPs exerted significantly reduced cytotoxic effects in Chlorella sp, in comparison with the pristine particles.


Assuntos
Chlorella , Nanopartículas , Poluentes Químicos da Água , Microplásticos , Nanopartículas/toxicidade , Poliestirenos/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade
6.
Ecotoxicol Environ Saf ; 247: 114226, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36306622

RESUMO

The digestive enzyme of plant are generally α-amylase. They functions enzyme that breakdown starch into maltose and sugars. This happens in the endosperm of the seed. Due to pollutants, this process get happened one of emergent xenobiotics are micro and nano plastics. This study involves the interaction 100 nm size of polystyrene nano plastic (PSNPs) on α-amylase. The hyperchromism of α-amylase - PSNPs conjugate's revealed that ground-state complex in a microenvironment. Fluorescence quenching happened when the concentration of PSNPs was increased. The Stern Volmer plot revealed binding constant (Ka) was 1.904 × 1019 M-1. S-1 while the quenching constant (Kq) was 1.036 × 1011 M-1, the blue shift of the peak showed static quenching. The binding constant was KA = 4.2 × 1012, the number of binding site on PSNPs for α-amylase was n = 1.12. The synchronous result showed a gradual reduction in the intensity of Trp residues because when the α-amylase interacts with PSNPs short-range π-π interaction happens around the Trp163 residues. The enzyme activity of α-amylase by 44 % and its IC50 value was found to be 100 µg/mL. The enzyme kinetics (Vmax) analysis showed the type of inhibition with and without PSNPs Vmax 769 and Vmax 303 µg/mL/min, uncompetitive inhibition respectively. The effect of PSNPs on the enzymatic activity of α-amylase showed structural alterations of the protein. Therefore the in vitro and in silico studies were shown evidence of interaction between α-amylase and PSNPs leads to conformational structural changes in α-amylase.


Assuntos
Poliestirenos , alfa-Amilases , Amilases , Microplásticos , Amido/química
7.
Ecotoxicol Environ Saf ; 238: 113612, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35561548

RESUMO

The use of polystyrene micro and nanoplastics in cosmetics and personal care products continues to grow every day. The harmful effects of their biological accumulation in organisms of all trophic levels including humans have been reported by several studies. While we have accumulating evidence on the impact of nanoplastics on different organ systems in humans, only a handful of reports on the impact of polystyrene nanoplastics upon direct contact with the immune system at the cellular level are avialable. The present study offers significant evidence on the cell-specific harmful impact of sulfate-modified nanoplastics (S-NPs) on human macrophages. Here we report that exposure of human macrophages to S-NPs (100 µg/mL) stimulated the accumulation of lipids droplets (LDs) in the cytoplasm resulting in the differentiation of macrophages into foam cells. The observed effect was specific for human and murine macrophages but not for other cell types, especially human keratinocytes, liver, and lung cell models. Furthermore, we found that S-NPs mediated LDs accumulation in human macrophages was accompanied by acute mitochondrial oxidative stress. The accumulated LDs were further delivered and accumulated into lysosomes leading to impaired lysosomal clearance. In conclusion, our study reveals that exposure to polystyrene nanoplastics stabilized with anionic surfactants can be a potent stimulus for dysregulation of lipid metabolism and macrophage foam cell formation, a characteristic feature observed during atherosclerosis posing a serious threat to human health.


Assuntos
Aterosclerose , Nanopartículas , Animais , Aterosclerose/metabolismo , Humanos , Metabolismo dos Lipídeos , Lisossomos/metabolismo , Macrófagos/metabolismo , Camundongos , Microplásticos/toxicidade , Nanopartículas/toxicidade , Poliestirenos/metabolismo , Poliestirenos/toxicidade
8.
Int J Mol Sci ; 23(10)2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35628427

RESUMO

(1) Background: The systemic administration of therapeutic agents to the intestine including cytokines, such as Interleukin-22 (IL-22), is compromised by damage to the microvasculature 24 hrs after total body irradiation (TBI). At that time, there is significant death of intestinal microvascular endothelial cells and destruction of the lamina propria, which limits drug delivery through the circulation, thus reducing the capacity of therapeutics to stabilize the numbers of Lgr5+ intestinal crypt stem cells and their progeny, and improve survival. By its direct action on intestinal stem cells and their villus regeneration capacity, IL-22 is both an ionizing irradiation protector and mitigator. (2) Methods: To improve delivery of IL-22 to the irradiated intestine, we gavaged Lactobacillus-reuteri as a platform for the second-generation probiotic Lactobacillus-reuteri-Interleukin-22 (LR-IL-22). (3) Results: There was effective radiation mitigation by gavage of LR-IL-22 at 24 h after intestinal irradiation. Multiple biomarkers of radiation damage to the intestine, immune system and bone marrow were improved by LR-IL-22 compared to the gavage of control LR or intraperitoneal injection of IL-22 protein. (4) Conclusions: Oral administration of LR-IL-22 is an effective protector and mitigator of intestinal irradiation damage.


Assuntos
Limosilactobacillus reuteri , Probióticos , Proteção Radiológica , Células Endoteliais , Interleucinas , Mucosa Intestinal/metabolismo , Intestinos , Interleucina 22
9.
J Environ Manage ; 303: 114128, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34823906

RESUMO

In the present study, ZnO-Fe3O4 nanoparticles were synthesized using the leaves of Camellia sinensis and immobilized in crosslinked alginate-chitosan polymer beads and tested for their photocatalytic applications. The prepared nanocomposite was used for the simultaneous adsorption and photocatalytic degradation of acid violet 7 (AV7) dye. The optimization of reaction conditions ensured higher dye removal efficacy up to 94.21 ± 1.02% using the nanocomposite under UV-C irradiation of 365 nm. The kinetics of the adsorption study fitted well with the pseudo-first-order reaction. The Langmuir model fitted better to the adsorption isotherms compared to the Freundlich and Temkin models. The mechanism of degradation was studied by analyzing the treated AV7 solution. The removal efficiency in tap water, groundwater, and lake water was 83.23 ± 0.4%, 69.13 ± 1.6%, and 67.89 ± 0.3%, respectively. The residual toxicity of the degraded AV7 solution was tested on model organisms like freshwater algae, Scenedesmus sp., and plant model, Allium cepa, demonstrating the lower toxicity of the degraded AV7 product. Finally, a cost-benefit analysis of the experiments was also carried out.


Assuntos
Camellia sinensis , Quitosana , Nanocompostos , Poluentes Químicos da Água , Óxido de Zinco , Adsorção , Alginatos , Compostos Azo , Concentração de Íons de Hidrogênio , Cinética , Naftalenossulfonatos , Extratos Vegetais , Água
10.
Curr Opin Colloid Interface Sci ; 54: 101458, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33814954

RESUMO

Nanoemulsions (NEs) of essential oil (EO) have significant potential to target microorganisms, especially viruses. They act as a vehicle for delivering antiviral drugs and vaccines. Narrowing of drug discovery pipeline and the emergence of new viral diseases, especially, coronavirus disease, have created a niche to use NEs for augmenting currently available therapeutic options. Published literature demonstrated that EOs have an inherent broad spectrum of activity across bacterial, fungal, and viral pathogens. The emulsification process significantly improved the efficacy of the active ingredients in the EOs. This article highlights the research findings and patent developments in the last 2 years especially, in EO antiviral activity, antiviral drug delivery, vaccine delivery, viral resistance development, and repurposing EO compounds against SARS-CoV-2.

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