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Liver disorders related to exposure to gasoline fumes in male rats and role of fenugreek seed supplementation Texto completo
2019
Abdrabouh, Abeer E.
Progressive effects of inhalation of gasoline fumes on the liver and the protective potential with fenugreek seed supplementation were evaluated in adult male rats. Twenty-four rats were divided into four groups, unexposed control and fenugreek groups, as well as exposed groups to gasoline fumes for 6 h/6 days/week for 10 weeks, with and without supplementation of fenugreek seed powder in food (5%w/w). Exposure to gasoline fumes resulted in a significant elevation in serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyl transferase, total bilirubin, total cholesterol, total triglycerides, and low-density lipoprotein, along with a significant decrease in high-density lipoprotein, total protein, and albumin contents compared to the control. Meanwhile, liver oxidative stress markers, malondialdehyde, hydrogen peroxide, and nitric oxide, were highly detected with decreased antioxidants, superoxide dismutase and catalase. Also, levels of inflammatory markers, interleukin(IL)-1β and IL-6, were significantly elevated with fibrotic markers, transforming growth factor (TGFβ1), fibroblast growth factor (FGF1), and collagen I. Histopathological studies illustrated that rats exposed to gasoline fumes have degenerated hepatocytes with cellular infiltration and necrotic areas, along with remarkable deposition of collagen fibers, suggesting an incidence of liver fibrosis. Administration of fenugreek seeds, rich with antioxidant and anti-inflammatory components, during gasoline exposure showed significant amelioration through suppressing oxidative stress and inflammation.
Mostrar más [+] Menos [-]Ameliorative effect of Spirulina platensis against lead nitrate–induced cytotoxicity and genotoxicity in catfish Clarias gariepinus Texto completo
2019
Abū al-Saʻūd, Muḥammad Ḥāmid Muʻawwaḍ | Soliman, Hamdy A. M. | Sayed, Alaa El-Din H.
The present study was designed to investigate the protective role of dietary supplementation of Spirulina platensis (SP) against cytotoxic and genotoxic effects of lead nitrate in Clarias gariepinus. Four groups of fishes were used: first group as control which fed on basal diet, second group fed on basal diet and exposed to (1 mg/L of lead nitrate), third group fed on diet containing 0.25% SP and exposed to (1 mg/L of lead nitrate), and fourth group fed on diet containing 0.5%SP and exposed to (1 mg/L of lead nitrate). Fish samples were taken at 2nd and 4th week of exposure. The hematological indices of lead nitrate–exposed group were decreased significantly compared to the control group at 2nd and 4th week of exposure. Lead nitrate caused a significant increase in the percentage of poikilocytosis, micronuclei, and apoptotic cells as well as comet tail length and olive tail moment compared with the control group at 2nd and 4th week of exposure. The highest level of damage was found on 4th week of exposure with all parameters. Dietary inclusion of SP ameliorated these cytotoxic and genetic changes, as well as this amelioration was concentration and time dependent. Consequently, the present study proposed that the addition of SP to the fish diet can be used as a promising protective agent to oppose cytotoxic and genotoxic effects of lead nitrate in aquaculture. Graphical abstract
Mostrar más [+] Menos [-]Phytoplankton functional groups in a monomictic reservoir: seasonal succession, ecological preferences, and relationships with environmental variables Texto completo
2019
Varol, Memet
The seasonal succession of phytoplankton functional groups (PFGs), their ecological preferences, relationships between environmental variables and PFGs, and ecological status were investigated in the Batman Dam Reservoir, a warm monomictic reservoir, located in the Tigris River basin of Turkey. Altogether 60 species, 19 functional groups, and 10 prevailing functional groups were identified, and prevailing functional groups showed strong seasonal changes. Centric diatoms Cyclotella ocellata (group B) and Aulacoseira granulata (group P) were dominant in the spring, with water mixing and low temperature. Groups F (Elakatothrix gelatinosa, Elakatothrix gelatinosa, and Sphaerocystis schroeteri), J (Pediastrum simplex and Coelastrum reticulatum), G (Eudorina elegans and Volvox aureus), LM (Ceratium and Microcystis), and H1 (Aphanizomenon flos-aquae and Anabaena spiroides) dominated the phytoplankton community from summer to mid-autumn, with thermal stratification. Groups H1 and P became dominant in the late autumn, with the breakdown of stratification. With the deepening of the mixing zone, groups P and T (Mougeotia sp.) were dominant in the winter. The reservoir was meso-eutrophic according to trophic state index values based on total phosphorus (TP), chlorophyll a, Secchi depth and total nitrogen, habitat preferences of PFGs, and diversity indices of phytoplankton. Redundancy analysis (RDA) revealed that NO₃–N, SiO₂, TP, pH, and water temperature (WT) were the most important environmental factors controlling PFGs in the BDR. Weighted averaging regression results indicated that among PFGs, groups F and T had a narrower tolerance range for WT, pH, and SiO₂, while groups G and T had a narrower tolerance range for TP and NO₃–N.
Mostrar más [+] Menos [-]Abundance and properties of microplastics found in commercial fish meal and cultured common carp (Cyprinus carpio) Texto completo
2019
Hanachi, Parichehr | Karbalaei, Samaneh | Walker, Tony R. | Cole, Matthew | Hosseini, Seyed V.
Microplastics (MPs) are environmental contaminants that are of increasing global concern. This study investigated the presence of MPs in four varieties of marine-derived commercial fish meal, followed by identification of their polymer composition using Fourier transform infrared (FTIR) spectroscopy. Exposure experiments were conducted on cultured common carp (Cyprinus carpio) by feeding four varieties of commercially available fish meal to determine relationships between abundance and properties of MPs found both in meal and in those transferred to cultured common carp. Mean particle sizes were 452 ± 161 μm (± SD). Fragments were the predominant shape of MP found in fish meal (67%) and C. carpio gastrointestinal tract and gills (65%), and polypropylene and polystyrene were the most present plastic polymers found in fish meal (45% and 24%, respectively) and C. carpio (37% and 33%, respectively). Positive relationships were found between MP levels in fish meal and C. carpio. This study highlights that marine-derived fish meal may be a source of MPs which can be transferred to cultured fish, thus posing a concern for aquaculture.
Mostrar más [+] Menos [-]Disinfection of water and wastewater by biosynthesized magnetite and zerovalent iron nanoparticles via NAP-NAR enzymes of Proteus mirabilis 10B Texto completo
2019
Zaki, Sahar A. | Eltarahony, Marwa Moustafa | Abd-El-Haleem, Desouky A.
Disinfection of water and wastewater strongly contributes to solving the problem of water shortage in arid/semi-arid areas; cheap and ecofriendly approaches have to be used to meet water quality standards. In the present study, a green synthesis of iron nanoparticles (INPs) under aerobic and anaerobic conditions via nitrate reductases (NAP/NAR) enzymes produced by Proteus mirabilis strain 10B were employed for this target. The biosynthesized INPs were characterized; UV-Vis spectroscopy revealed surface plasmon resonance at 410 (aerobic) and 265 nm (anaerobic). XRD indicated crystalline magnetite ((MNPs) aerobically synthesized) and zerovalent INPs (ZVINPs anaerobically synthesized). EDX demonstrated strong iron signal with atomic percentages 73.3% (MNPs) and 61.7% (ZVINPs). TEM micrographs illustrated tiny, spherical, periplasmic MNPs (1.44–1.92 nm) and cytoplasmic ZVINPs with 11.7–60.8 nm. Zeta potential recorded − 31.8 mV (ZVINPs) and − 66.4 mV (MNPs) affirming colloidal stability. Moreover, the disinfection power of INPs was evaluated for standards organisms and real water (fresh, sea and salt mine) and wastewater (municipal, agricultural and industrial) samples. The results reported that INPs displayed higher antagonistic effect than iron precursor, 700 and 850 μg/mL of MNPs and ZVINPs, respectively, was sufficient to show a drastic algicidal effect on algal growth. Both types of INPs demonstrated obvious dose-dependent antibiofilm efficiency. Due to their smaller size, MNPs were more efficient than ZVINPs at the suppression of microbial growth in all examined water samples. Overall, MNPs showed superior antagonistic activity, which promotes their exploitation in enhancing water/wastewater quality.
Mostrar más [+] Menos [-]Sulfate radical-mediated degradation of phenol and methylene blue by manganese oxide octahedral molecular sieve (OMS-2) activation of peroxymonosulfate Texto completo
2019
Wei, Jing | Li, Xiaoming | Yang, Qi | Wu, You | Huang, Xiaoding | Tao, Ziletao | Xu, Qiuxiang | Zhu, Xiaofei | Wang, Dongbo
Activation of peroxymonosulfate (PMS) has been concentrated on degrading refractory organic pollutants owing to the generation of sulfate radical ([Formula: see text]) with high standard redox potential. In this study, manganese oxide octahedral molecular sieve (OMS-2) with cryptomelane type was synthesized by a new hydrothermal method to activate PMS for the degradation of phenol and methylene blue (MB) in water. The as-prepared composites were fully characterized, and the effects of PMS dosage, OMS-2 dosage, initial pollutant concentration, pH, and chloride on the degradation of phenol were elaborately investigated. Moreover, the phenol degradation was evaluated through the variations of total organic carbon (TOC) and three-dimensional excitation emission matrix (3D-EEM), and reaction intermediates were also investigated. Both electron spin resonance (ESR) spectra and comparative experiments suggested [Formula: see text] and hydroxyl radical (HO•) took part in the phenol degradation and [Formula: see text] was more significant than HO•. The fine degradation efficiency of phenol in different water source, as well as the stability after continuous use, indicated the possible application of PMS/OMS-2 in real wastewater treatment.
Mostrar más [+] Menos [-]Hepatoprotective activity of Uncaria tomentosa extract against sub-chronic exposure to fipronil in male rats Texto completo
2019
The effects of fipronil (FPN) on the liver of rats were studied. Rats (n = 6) were treated with 9.7 mg/kg (1/10 of FPN LD₅₀), and other rats (n = 6) received 120 mg/kg of 10% Uncaria tomentosa extract, while a mixture of 9.7 mg/kg FPN and 120 mg/kg of 10% Uncaria tomentosa extract were administered orally to the rats (n = 6) daily for 6 weeks. Body, hepatic weights, liver enzymes, and lipid profile were determined. Hepatic activities of MDA, TNO, TAC, TNF-α, and IL-6 in liver homogenate were measured. Immunohistochemistry of NF-kB and liver histopathology were performed. Fipronil-treated rats had a significant (P = 0.02) lower weight gain. Moreover, relative liver weight was significantly (P = 0.003) increased in FPN-treated rats. Rats administrated with FPN exhibited a significantly (P = 0.02) higher liver enzymes and promoted levels of MDA, TNO, TNF-α, and IL-6 (P < 0.0001) than that in the other groups. Immunostaining of NF-κB was increased (P < 0.0001) in FPN-treated rats. Interestingly, Uncaria tomentosa alone or with FPN decreased the liver immunostaining of NF-κB. In conclusion, FPN produced liver injury through lipid peroxidation and stimulation of NF-κB. However, Uncaria tomentosa combated the oxidative stress and liver damage induced by FPN via inhibition of NF-κB.
Mostrar más [+] Menos [-]Toxicity of erythromycin to Oncorhynchus mykiss at different biochemical levels: detoxification metabolism, energetic balance, and neurological impairment Texto completo
2019
Toxicity of erythromycin to Oncorhynchus mykiss at different biochemical levels: detoxification metabolism, energetic balance, and neurological impairment Texto completo
2019
During the last decades, the presence of antibiotics in different aquatic compartments has raised increasing interest and concern, since these compounds are usually persistent and bioactive pseudo pollutants. Erythromycin (ERY) is a macrolide antibiotic, prescribed for human and veterinary medicines but also used in aquaculture and livestock production. Taking into account the recorded environmental levels of ERY, its toxicity to non-target organisms has become a still poorly studied issue, particularly in fish. In this sense, this study investigated the acute and chronic effects of realistic levels of ERY on Oncorhynchus mykiss (rainbow trout), namely, through the quantification of the activity of enzymes involved in different biochemical pathways, such as detoxification (phase I—7-ethoxyresorufin O-deethylase (EROD); phase II—glutathione S-transferases (GSTs), uridine-diphosphate-glucuronosyltransferases (UGTs)), neurotransmission (acetylcholinesterase (AChE)), and energy production (lactate dehydrogenase (LDH)). Both types of exposure caused significant increases in EROD activity in liver of O. mykiss; an increase in GST activity in gills after chronic exposure was also observed. UGT branchial activity was significantly depressed, following the long-term exposure. Thus, EROD, GST, and UGT enzymatic forms seem to be involved in the biotransformation of ERY. In terms of neurotransmission and preferential pathway of energy homeostasis, the exposed organisms appear not to have been affected, as there were no significant alterations in terms of AChE and LDH activities, respectively. The here-obtained data suggest that the observed alterations in terms of detoxification enzymes may have prevented the establishment of a set of toxic responses, namely, neurotoxic and metabolic disorders.
Mostrar más [+] Menos [-]Toxicity of erythromycin to Oncorhynchus mykiss at different biochemical levels: detoxification metabolism, energetic balance, and neurological impairment Texto completo
2019
Rodrigues, Sara | Antunes, Sara C. | Correia, Alberto T. | Nunes, Bruno
During the last decades, the presence of antibiotics in different aquatic compartments has raised increasing interest and concern, since these compounds are usually persistent and bioactive pseudo pollutants. Erythromycin (ERY) is a macrolide antibiotic, prescribed for human and veterinary medicines but also used in aquaculture and livestock production. Taking into account the recorded environmental levels of ERY, its toxicity to non-target organisms has become a still poorly studied issue, particularly in fish. In this sense, this study investigated the acute and chronic effects of realistic levels of ERY on Oncorhynchus mykiss (rainbow trout), namely, through the quantification of the activity of enzymes involved in different biochemical pathways, such as detoxification (phase I-7-ethoxyresorufin O-deethylase (EROD); phase II-glutathione S-transferases (GSTs), uridine-diphosphate-glucuronosyltransferases (UGTs)), neurotransmission (acetylcholinesterase (AChE)), and energy production (lactate dehydrogenase (LDH)). Both types of exposure caused significant increases in EROD activity in liver of O. mykiss; an increase in GST activity in gills after chronic exposure was also observed. UGT branchial activity was significantly depressed, following the long-term exposure. Thus, EROD, GST, and UGT enzymatic forms seem to be involved in the biotransformation of ERY. In terms of neurotransmission and preferential pathway of energy homeostasis, the exposed organisms appear not to have been affected, as there were no significant alterations in terms of AChE and LDH activities, respectively. The here-obtained data suggest that the observed alterations in terms of detoxification enzymes may have prevented the establishment of a set of toxic responses, namely, neurotoxic and metabolic disorders. | published
Mostrar más [+] Menos [-]Sub-chronic exposure to Tris(1,3-dichloro-2-propyl) phosphate induces sex-dependent hepatotoxicity in rats Texto completo
2019
As the application and environmental release of tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) are being increased rapidly, serious concerns have been raised regarding its adverse effects on human health. Exposure to TDCIPP has been implicated in hepatotoxicity, but the molecular mechanisms remain unclear. Here, both male and female Sprague Dawley rats were administered TDCIPP with 125, 250, or 500 mg/kg/day for 12 weeks. Then the ultrastructure of liver, biochemical indicators in serum and liver, and hepatic gene expression were analyzed to reveal molecular mechanisms of hepatotoxicity induced by TDCIPP. Continuous TDCIPP exposure decreased body weight, particularly in 500 mg/kg/day TDCIPP-exposed males, and dose dependently increased the ratio of liver to body weight in both genders. The decreased levels of triglyceride, cholesterol, and transaminase in the serum and livers were observed in both genders after TDCIPP exposure, which indicated dysfunction in the hepatic metabolism. Liver histopathology revealed hepatocellular damages in males and females after TDCIPP exposure. The transcriptomic analysis indicated that TDCIPP exposure significantly changed pathways of bile acid metabolism, inflammatory response, oxidative phosphorylation and carcinogenicity in 250 and 500 mg/kg/day TDCIPP-exposed males and 500 mg/kg/day TDCIPP-exposed females, and there was no statistical significance in any other TDCIPP-exposed groups. The transcriptional analysis showed that TDCIPP exposure led to oxidative stress in the livers of rats, thereby increasing the inflammatory response and promoting mechanisms of carcinogenesis in both genders. Finally, TDCIPP led to more severe adverse phenotypic effects in male than female rats.
Mostrar más [+] Menos [-]Effective adsorption of zinc on magnetic nanocomposite of Fe3O4/zeolite/cellulose nanofibers: kinetic, equilibrium, and thermodynamic study Texto completo
2019
In this paper, the adsorption behavior of zinc onto magnetic zeolite/cellulose nanofibers (MZNF) was studied. The prepared adsorbent was characterized by SEM, FTIR, and VSM analyses. The mass ratio of adsorbent in composite, pH, contact time, adsorbent dosage, initial Zn⁺² concentration, temperature, and agitation speed were investigated in batch experiments. The results showed that zeolite played an important role in the prepared nanocomposite due to its great surface area. pH 7 exhibited the highest Zn⁺² removal efficiency. Rapid adsorption at the first 30 min of the reaction is one of the advantages of the prepared adsorbents. Moreover, increase at temperature led to higher efficiency and maximum efficiency was attained at 30 °C. Under optimum conditions, MZNF showed removal efficiency of 96% and maximum adsorption capacity of 9.45 mg/g. The presence of the competing ions did not reduce the efficiency of the process and adsorption efficiency was higher than 93%. The calculated RSD of 1.42% exhibits the suitability of the process. Equilibrium data were examined by various isotherms and kinetics equations. It was concluded that Pseudo second-order model and Langmuir models described the adsorption process well. Based on these results, MZNF obtained in this work can be served as a promising candidate for Zn⁺² removal in wastewater.
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