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关键词： Cyanobacteria   Broad-spectrum antibiotics   Toxicity   Physiology   Biochemical composition   GLUTATHIONE-S-TRANSFERASE   CHLOROPHYLL-A   PROTEIN   WATER   STRESS  

摘要： The increased production, consumption, and release of antibiotics account for their frequent contamination of aquatic ecosystems and detection in different biological matrices. Several antibiotics affect non-target organisms such as algae, cyanobacteria, zooplankton, and fish, making investigations on them very crucial for the health and maintenance of biodiversity. The impact of broad-spectrum antibiotics like ciprofloxacin (CPX) on toxin-producing and non-toxin-producing cyanobacteria has been poorly investigated. Therefore, the present study investigated the physiological and toxicological effects of CPX on Microcystis aeruginosa EAWAG 198, Microcystis aeruginosa LE3, and Microcystis flos-aquae UTEX-LB 2677. CPX caused a significant (p < 0.05) decrease in the cell densities and chlorophyll-a of the three strains. The antibiotic caused oxidative stress in all the strains, as demonstrated by a significant rise in the levels of intracellular hydrogen peroxide (H2O2) of the treated cultures at 96 h post-exposure. Lipid peroxidation and the activity of the antioxidant enzyme-peroxidase (POD) and glutathione-S-transferase (GST)-of the cultures were significantly (p < 0.05) altered. Exposure to CPX generally stimulated the production of biomolecules such as total proteins, lipids, and total carbohydrates as a function of increasing exposure concentration. The exception to the general trend was M. aeruginosa EAWAG 198, a non-toxin-producing strain, which suffered a significant decline in carbohydrate content during exposure to CPX. This study revealed that environmentally relevant levels of CPX could alter the population dynamics, photosynthesis, biochemical composition, and the general physiology of Microcystis species/strains in aquatic ecosystems.

关键词： Chlorophyll   Carotenoid   Enzymatic activities   Leaf relative water   Lipid peroxidation   Medicinal plants   Proline   Soil pollution   CHLOROPHYLL FLUORESCENCE   STRESS   TOXICITY   SELENIUM   PLANTS   PB  

摘要： Heavy metals bioremediation by medicinal plants is an important research issue, which has yet to be investigated. Matricaria chamomilla accumulation of soil cadmium (Cd, 0, 10 and 40 mg/kg) and lead (Pb, 0, 60 and 180 mg/kg) affecting plant biochemical properties L. at different growth stages in the greenhouse and field was investigated. The 10-kg experimental pots (located in the greenhouse and field with 80% of field capacity moisture) were filled with the treated soils, and were planted with M. chamomilla L. seeds (three replicates). Plants were sampled to determine their biochemical properties including Cd and Pb contents, pigments, proline (Pro), leaf relative water (LRW), lipid peroxidation (LX), and superoxide dismutase (SOD, EC 1.15. 1.1), and catalase (CAT, EC 1.***.1.6) activities. Soil final concentration of Cd and Pb was also determined. Heavy metal stress significantly decreased plant pigment contents; however, it significantly increased plant PRO, LRW, LX and SOD, and not CAT. Heavy metal, growth stage, growth location, and their interactions significantly affected plant heavy metal concentrations. Interestingly, although significantly higher concentration of Cd was observed in plant aerial part under greenhouse conditions, plant roots had significantly higher concentrations of Cd under field conditions, and it was reverse for Pb. Increased concentration of Cd and Pb significantly enhanced plant Pro content and the highest one was resulted by Pb3 (913.46 mg/g fresh weight) significantly higher than other treatments including Cd3 (595.34 mg/g fresh weight). M. chamomilla is a suitable species for the bioremediation of soils polluted with Cd and Pb.

关键词： Cardiovascular risk factors   Complications   HbA1c   Type 1 diabetes   CARDIOVASCULAR-DISEASE   YOUNG-ADULTS   MORTALITY   REGISTER   RISK  

摘要： Background There is limited data on glycaemic control and cardiovascular risk factor management in newly diagnosed individuals with type 1 diabetes in the first 2 years. Methods Retrospective, single centre study from the North West of England, newly diagnosed with type 1 diabetes between 2014 and 2018 (n = 58). HbA1c, blood pressure, lipids and body mass index (BMI) data were collected from electronic patient records from the time of diagnosis until the end of 2 years, stratified by age 16-24 years or >= 25 years at presentation. Results For those aged 16-24 years (n = 31), median (IQR), HbA1c improved at 6 months from 83 (63-93) to 51.5 (46-75) mmol/mol (p = 0.001) and remained stable 6-24 months. For those >= 25 years (n = 27), HbA1c declined from 91 (70-107) to 65 (50-89) mmol/mol, (p < 0.01) at 6 months and declined further to 52 mmol/mol (44-70) at 24 months. At 24 months, 27.8% of all individuals had an HbA1c >= 69 mmol/mol. Approximately, a third met LDL (< 2 mmol/L) and total cholesterol (< 4 mmol/L) targets. A total of 58.6% of individuals were overweight/obese (BMI > 25 kg/m(2)) at 24 months compared to 45.8% at baseline. There were no significant blood pressure changes during the follow-up. Conclusions In both age groups, significant improvement of HbA1c occurred within the first 6 months of diagnosis with no statistical difference between the two groups at any of the time points up to 24 months. Despite significant improvements in HbA1c, majority had levels > 53 mmol/mol at 24 months. Alongside the high incidence of obesity and dyslipidaemia, our data support the need for further intensification of therapy from diagnosis of type 1 diabetes.

关键词： PYGM  

关键词： Extracellular enzyme   Prebiotics   Purification   Ultrasound   Biocatalysis   FRUCTOSYLTRANSFERASE   FRUCTOOLIGOSACCHARIDES   WASTES  

摘要： beta-fructofuranosidases (EC3.***.1.26) are members of the GH32 family of glycoside hydrolases, which include more than 390 enzymes of vegetable and microbial origins, used in several biotechnological applications. Thus, this research aimed to produce a beta-fructofuranosidase obtained by Aspergillus tamarii through solid state fermentation, and to purify by Aqueous Two-Phase System (ATPS). Summary results presented the optimal parameters to produce the beta-fructofuranosidase used wheat bran as a substrate at 30 degrees C for 48 h, and purification process using ATPS with polyethylene glycol and sodium citrate (PEG/sodium citrate), where the beta-fructofuranosidase preferably partitioned to the salt-rich phase, the best run (24% of PEG 400, 20% sodium citrate, pH 8) which presented a higher purification factor 6.42 with 12.39 U/mL activity and 352% yield. Optimum parameter was pH 5.15 and temperature of 55 degrees C, respectively. The purified enzyme showed excellent thermal stability and exhibited a half-life of 60 min at 65 degrees C. Kinetics results for enzyme showed for Sucrose substrate the enzyme showed K-m of 42.9 +/- 2.21 mM and V-max of 180.2 +/- 2.8 mu M min(-1) mg(-1) of protein. Although V-max was the highest for 1-Kestose (219.4 +/- 2.7 mu M min(-1) mg(-1) of protein) the preferred substrate of Aspergillus tamarii (beta-fructofuranosidase (beta-FFase)) was Nystose (K-m of 3.8 +/- 0.15 mM). SDS-PAGE revealed a single band of protein at similar to 66 kDa. Finally, this study demonstrated the potential of ATPS to purify a beta-fructofuranosidase with application in biotechnological field aiming to functional foods.

关键词： Nano minerals   Seabass   Growth rate   Antioxidative status   Immunity   TROUT ONCORHYNCHUS-MYKISS   MUSCLE COMPOSITION   RAINBOW-TROUT   GLUTATHIONE-PEROXIDASE   OXIDATIVE STRESS   NILE TILAPIA   CRUCIAN CARP   FISH   RESISTANCE   CATFISH  

摘要： The current study investigated the role of selenium (Se) nanoparticles on the growth performance, hemato-biochemical indices, antioxidative, and immune-related genes of European seabass (Dicentrarchus labrax). Therefore, fish with initial weight of 20.53 +/- 0.10 g/fish were fed diets with 0, 0.25, 0.5, and 1 mg Se nanoparticles/kg diet for 90 days. The final body weight, weight gain, and specific growth rate of fish fed dietary nano-Se varying levels were significantly higher than the control with the highest performances and lowest FCR in the group of fish fed nano-Se at 0.5 mg/kg. The values of Hb, PCV, RBCs, and WBCs were significantly higher in fish fed varying levels of Se nanoparticles than fish fed the basal diets. The values of total serum protein and globulin were significantly higher in fish fed varying levels of Se nanoparticles than fish fed the basal diets. Additionally, globulin had higher value in the group of fish fed 0.25 and 0.5 mg nano-Se/kg than fish fed 1 mg nano-Se/kg (P < 0.05). No significant alterations were observed on albumin, ALT, and AST variables (P > 0.05). Phagocytic index, phagocytic, lysozyme activities were significantly higher in fish fed varying levels of Se nanoparticles than fish fed the basal diets in a dose dependent manner (P < 0.05). Further, SOD activity had higher value in the group of fish fed 0.25 and 0.5 mg nano-Se/kg than fish fed 1 mg nano-Se/kg, whereas CAT was increased in the group of fish fed dietary 0.5 mg nano-Se/kg diet (P < 0.05). The level of MDA was significantly lowered by dietary nano-Se where the group of fish fed 0.25 mg/kg had the lowest level followed by those fed 0.5 and 1 mg/kg. The expression ofGH,IGF-1,IL-8, andIL-1 beta genes had the highest mRNA levels in the group of fish fed 0.25 and 0.5 mg/kg followed by those fed 1 mg/kg, whereasHSP70was downregulated. Based on the overall results, Se nanoparticles are recommended at the rate of 0.5-1 mg/kg diet to maintain the optimal growth performance, h

关键词： Copper amino acid complex   Laying hen   Laying performance   Blood parameter   Histopathology   DIETARY COPPER   RELATIVE BIOAVAILABILITY   SAFETY EVALUATION   SULFATE   LIVER   SUPPLEMENTATION   CHOLESTEROL   METHIONINE   TOXICITY   CHITOSAN  

摘要： The objective of the study was to evaluate the maximum tolerance limit of amino acid copper complex (Cu-Lys-Glu) for laying hens by measuring their laying performance, hematological and serum biochemical parameters, organ index, and histopathology. A total of 450 18-week-old Beijing White layers were randomly allocated to 5 groups (90 birds per group) with 6 replicates of 15 birds each. After a 2-week acclimation on a basal diet (analyzed copper content 8.63 mg/kg), the birds were fed diets supplemented with 0 (control), 15, 75, 150, and 300 mg Cu/kg as Cu-Lys-Glu for 10 weeks. Results showed that, compared with the control group, dietary supplementation with 15, 75, and 150 mg Cu/kg as Cu-Lys-Glu did not affect (P > 0.05) laying performance, whereas hens receiving with 300 mg Cu/kg significantly decreased (P < 0.001) the laying rate as compared with the control. No significant differences (P > 0.05) were observed among the hens receiving 0, 15, 75, and 150 mg Cu/kg as Cu-Lys-Glu in hematological and serum biochemical parameters, organ indexes, and histopathological changes. However, hens receiving 300 mg Cu/kg significantly increased (P < 0.05) the concentrations of mean corpuscular volume (MCV), albumin (ALB), total bilirubin (TBILI), alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), urea nitrogen (UN), and creatinine (CRE), as well as caused severe microscopic histopathological changes in the liver and kidney. In conclusion, 150 mg Cu/kg as Cu-Lys-Glu is identified as no-side-effect supplementation level in laying hens after daily administration for 70 days.

关键词： DANIO-RERIO   DNA-DAMAGE   STRESS   FISH   PESTICIDES   TOXICITY   NEONICOTINOIDS   INSECTICIDES   DIAZINON   TISSUES  

摘要： Imidacloprid (IMI) is an insecticide used worldwide, a neonicotinoid that could cause toxicity in non-target organisms. Zebrafish (Danio rerio) is a model organism widely used in different fields of research such as behavioral studies, biochemical parameters as well as neurotoxicity research. Here, we investigate whether the exposure to three concentrations (0.15, 15, and 45 mu g/L) of IMI for 96 h alters responses in zebrafish. Oxidative stress parameters and acetylcholinesterase activity (AChE) as well as the behavioral responses of locomotion were measured. IMI exposure decreased distance traveled in fish exposed to the 45 mu g/L. In the exploratory activity, time spent and transitions to the top area of the water column decreased in fish exposed to all concentrations of IMI. In addition, exposures to 45 and 15 mu g/L of IMI decreased episodes of erratic movement in the zebrafish. Exposures to IMI at a concentration of 45 mu g/L decreased the time spent in erratic movements and increased the time spent with no movement (i.e., "freezing"). Glutathione S-transferase (GST) activity was increased in the brain of zebrafish exposed for 96 h to concentrations of 0.15 and 45 mu g/L. Brain AChE activity was reduced and the levels of carbonyl protein (CP) increased in brain of zebrafish at concentrations of 15 and 45 mu g/L. Lipid peroxidation measured by TBARS and, also non-protein thiols (NPSH) did not show any variation in the brain of zebrafish exposed to IMI. Changes in the activity of cholinergic neurotransmitters in the brain tissues of zebrafish indicate IMI toxicity. Exposures of fish over 96 h to IMI at a nominal concentration of 45 mu g/L caused more extensive sublethal responses in zebrafish, but this concentration is well above those expected in the aquatic environment. Studies are warranted to evaluate the effects on behavior and biomarker responses in fish exposed over longer periods to IMI at environmentally relevant concentrations.

关键词： Aluminum phosphide   Cardiotoxicity   Mitochondrial toxicity   Oxidative stress   Taurine   INDUCED OXIDATIVE STRESS   MITOCHONDRIAL DYSFUNCTION   OXIDE NANOPARTICLES   MAGNESIUM-OXIDE   APOPTOSIS   TOXICITY   BENEFIT   PROTECTION  

摘要： Background: Aluminum phosphide (AlP) causes severe cardiotoxicity. Taurine has been chosen for the present study because of its positive known effects on cardiac injuries. Method: To evaluate AlP-induced cardiotoxicity, the animals were divided into seven groups, including the control group, the taurine group (500 mg/kg), AlP with LD50 dose, AlP + taurine 20, 50, 100, and 200 mg/kg group. To assess cardiac hemodynamic parameters, Wistar rats received taurine intraperitoneally 60 min after AlP gavage. Cardiac hemodynamic parameters were evaluated for 180 min. To study biochemical parameters, 24 h after AlP treatment, the animals were sacrificed, and heart tissues were collected. Result: ECG, BP, and HR abnormalities of AlP poisoning were improved by taurine treatment. AlP induced biochemical alterations including complexes I and IV activities, the ADP/ATP ratio, mitochondrial membrane potential, cytochrome C release, and oxidative stress biomarkers ameliorated by taurine. Moreover, taurine improved apoptosis, as well as lessened CC-MB and troponin I levels. Also, there were no significant changes between taurine 500 mg/kg and the control group in tests. Conclusion: The present findings showed that taurine could be a possible candidate for AlP cardiotoxicity treatment via the effect on mitochondrial electron transfer chain and maintaining intracellular ATP balance.

关键词： Garlic   SRAP marker   Diversity analysis   Allicin   ALLIUM-SATIVUM L.   POPULATION-STRUCTURE   PYRUVIC-ACID   COLLECTION   SET   ANTIOXIDANTS   LOCATION   STRATEGY   ECOTYPES   ALLICIN  

摘要： The characterization of garlic germplasm improves its utility, despite the fact that garlic hasn't been used much in the past. Garlic has an untapped genetic pool of immense economic and medicinal value in India. Hence, using heuristic core collection approach, a core set of 46 accessions were selected from 625 Indian garlic accessions based on 13 quantitative and five qualitative traits. The statistical measures (CV per cent, CR per cent, VR per cent) were used to sort the core set using Shannon-Wiener diversity index and the Nei diversity index. In addition, the variation within the core set was tested for 18 agromorphological and six biochemical characteristics (allicin, phenol content, pyruvic acid, protein, allyl methyl thiosulfinate (AMTHS), and methyl allyl thiosulfinate (MATHS)). Further study of the core set's molecular diversity was performed using sequence related amplified polymorphism (SRAP) markers, which revealed a wide range of diversity among the core set's accessions, with an average polymorphism efficiency (PE) of 80.59 percent, polymorphism information content (PIC) of 0.29, effective multiplex ratio (EMR) of 3.51, and marker index (MI) of 0.99. The findings of this study will be useful in identifying high yielding, elite garlic germplasm lines with the trait of interest. Since this core set is indicative of total germplasm, these selected breeding lines will be used for genetic improvement of garlic in the future. (c) 2021 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://***/licenses/by-nc-nd/4.0/).