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381.
Heavy metals, including cadmium (Cd), lead (Pb) and mercury (Hg) act as nephrotoxic agents, particularly in the renal cortex. The aim of the study was to determine the concentrations of Cd, Pb and Hg in kidneys removed from patients due to lesions of various etiologies and from patients after the rejection of transplanted kidneys. Additionally, we determined the influence of selected biological and environmental factors on the concentrations of toxic metals. The study material consisted of kidneys with tumor lesions (n = 27), without tumors (n = 7) and its extracted grafts (n = 10) obtained from patients belongs to the north-western areas of Poland. The determined metal concentrations in the renal cortex and medulla may be arranged in the following descending order: Cd > Pb > Hg. The highest concentrations of Cd and Hg were found in the cortex, while the maximum content Pb was observed in the medulla. Significant correlations were found in the concentrations of the same metals between cortex and medulla and between Pb and Hg in the renal medulla. Pb content was higher in the renal medulla of men than in the cortex of the elderly (above 60 years of age). The highest concentrations of Pb and Hg were found in the cortex and medulla, of the kidneys had not neoplastic changes, and lower content of these metals were found in the extracted kidney grafts. In summary, renal grafts accumulate less heavy metals than cancerous kidneys, what could have been caused by immunosuppressors taken by the graft recipients. Moreover, sex, age and smoking are key factors responsible for xenobiotics concentrations.  相似文献   
382.
The aim of this study was to assess the effect of infection with Fusarium fungi and chemical protection on the contents of phenolic acids and antioxidative potential of extracts from grains of 23 wheat genotypes. Based on chemical analyses including abiotic factors such as weather conditions and the location of the plantation, the authors attempted to clarify non-enzymatic antioxidative response mechanisms to two different stressors in 23 wheat genotypes. Based on chemical analysis, it was found that mass infection with fungi from the genus Fusarium induces defence mechanisms of the plant, which results in an increased production of phenolic acids, mainly those, which are substrates for the production of acids exhibiting antimicrobial action. This mechanism is confirmed by the analyses of antioxidant activity, which also increases significantly during fungal infection, connected with the production of mycotoxins. In the course of chemical plant protection, significant changes were observed in the production of phenolic acids. Even if antioxidant activity was not higher in comparison to the control, an increased production of certain phenolic acids was recorded, which suggests stimulation of the resistance system of the plant, at a simultaneous complete response of antioxidative mechanisms, as it takes place during fungal infection.  相似文献   
383.
The leaves of eight Salix species/hybrids were collected from two sites with different soil conditions including metal concentrations to investigate the concentration of Cu, Zn and Pb, phenolic profile and antioxidant scavenging activity. Cu, Zn and Pb, phenolic content and scavenging activity in leaves from the control area (lower concentration of metals in soil) (site C) were lower than in plants cultivated in site G (higher concentration of metals in soil). The content of Cu, Pb and Zn in leaves was in the range 9.21 (site G)–52.36 (site G), 0.41 (site C)?12.03 (site C) and 27.23 (site C)–214.44 (site G) mg?kg?1, respectively. Total phenolic content ranged between 18.19 (site C) and 84.71 (site G) mg gallic acid equivalent per gram of dry matter. Total flavonoid content was between 7.98 (site C) and 54.48 (site G) mg catechin g?1?d.m. The scavenging effect on 2,2-diphenyl-1-picrylhydrazyl˙ ranged between 33.6% (site C) and 56.3% (site G). Phenolic acids, myricetin and quercetin were quantified in leaves. The results show that phenolics are involved during adaptive mechanisms under elevated content of Cu, Pb and Zn in soil. Changes in the phenolic composition in leaves can be suggested as indicators of metal stress in Salix plants.  相似文献   
384.
ABSTRACT

The present study investigated the content of 62 elements in the fruiting bodies of Lentinula edodes (Shiitake mushroom) cultivated commercially in Poland on various substrates from 2007–2015. The general mean content (mg kg?1 dry weight (DW)) of the studied elements ranked in the following order: K (26,335) > P (11,015) > Mg (2,284) > Ca (607) > Na (131) > Zn (112) > Fe (69) > Mn (33) > B (32) > Rb (17) > Cu (14.5) > Al (11.2) > Te (2.9) > As (1.80) > Cd (1.76) > Ag (1.73) > Nd (1.70) > Sr (1.46) > Se (1.41) > U (1.11) > Pt (0.90) > Ce (0.80) > Ba (0.61) > Co (0.59) > Tl (0.58) > Er (0.50) > Pb (0.42) > Li (0.40) > Pr (0.39) > Ir (0.37) > In (0.35) > Mo (0.31) > Cr (0.29) > Ni (0.28) > Sb (0.26) > Re (0.24) > Ti (0.19) > Bi (0.18) > Th (0.12) > La (0.10) = Pd (0.10) > Os (0.09) = Zr (0.09) > Rh (0.08) > Ho (0.07) > Ru (0.06) > Sm (0.04) = Eu (0.04) = Tm (0.04) > Gd (0.03) > Sc (0.02) = Y (0.02) > Lu (0.01) = Yb (0.01) = V (0.01). The contents of Au, Be, Dy, Ga, Ge, Hf, and Tb were below the limits of detection (0.02, 0.02, 0.01, 0.01, 0.01, 0.01, 0.02 mg kg?1 respectively). The concentrations of Al, As, B, Ba, Ca, Cd, Cr, Er, Fe, In, Lu, Mn, Nd, Sr, Ti, Tm, and Zr were comparable over the period the mushrooms were cultivated. The study revealed that Lentinula edodes contained As and Cd at levels potentially adverse to human health. This highlights the need to monitor these elements in food products obtained from this mushroom species and ensure that only low levels of these elements are present in cultivation substrates.  相似文献   
385.

This study determined the susceptibility of cultured soil microorganisms to the effects of Ekodiesel Ultra fuel (DO), to the enzymatic activity of soil and to soil contamination with PAHs. Studies into the effects of any type of oil products on reactions taking place in soil are necessary as particular fuels not only differ in the chemical composition of oil products but also in the composition of various fuel improvers and antimicrobial fuel additives. The subjects of the study included loamy sand and sandy loam which, in their natural state, have been classified into the soil subtype 3.1.1 Endocalcaric Cambisols. The soil was contaminated with the DO in amounts of 0, 5 and 10 cm3 kg−1. Differences were noted in the resistance of particular groups or genera of microorganisms to DO contamination in loamy sand (LS) and sandy loam (SL). In loamy sand and sandy loam, the most resistant microorganisms were oligotrophic spore-forming bacteria. The resistance of microorganisms to DO contamination was greater in LS than in SL. It decreased with the duration of exposure of microorganisms to the effects of DO. The factor of impact (IFDO) on the activity of particular enzymes varied. For dehydrogenases, urease, arylsulphatase and β-glucosidase, it had negative values, while for catalase, it had positive values and was close to 0 for acid phosphatase and alkaline phosphatase. However, in both soils, the noted index of biochemical activity of soil (BA) decreased with the increase in DO contamination. In addition, a positive correlation occurred between the degree of soil contamination and its PAH content.

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386.

The present study determines the influence of three ionic liquids (ILs) containing cations with diversified structure on the growth and development of spring barley seedlings and common radish leaves. Increasing amounts of 1-butyl-1-methylpyrrolidinium hexafluorophosphate [Pyrrol][PF6], 1-butyl-1-methylpiperidinium hexafluorophosphate [Piper][PF6], and 1-butyl-4-methylpyridinium hexafluorophosphate [Pyrid][PF6] were added to the soil on which both plants were cultivated. The results of this studies showed that the applied ILs were highly toxic for plants, demonstrated by the inhibition of length of plant shoots and roots, decrease of fresh mass, and increase of dry weight content. Common radish turned out to be the plant with higher resistance to the used ILs. The differences in the cation structure did not influence phytotoxity of ILs for spring barley. Furthermore, all ILs led to a decrease of photosynthetic pigments, which was directly followed by decreased primary production in plants. Oxidative stress in plants occurred due to the presence of ILs in the soil, which was demonstrated by the increase of malondialdehyde (MDA) content, changes in the H2O2 level, and antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD). The changes in the chlorophyll contents and the increase of POD activity turned out to be the most significant oxidative stress biomarkers in spring barley and common radish. Both spring barley and radish exposed to ILs accumulated a large amount of fluoride ion.

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387.
The aim of the experiment was to study the influence of acrylamide (ACR) on major antioxidants in the lungs of Swiss mice. The experiment was conducted on male mice that were 8 weeks old. The mice were exposed to ACR at a single dose of 26 µg per animal, which was administered orally. Mice were anesthetized 3, 24, and 48 h after the ACR gavage. Next, histopathological and biochemical analyses of GSH concentration and the activities of SOD, GPx, and CAT were performed in the lungs. Animals exposed to ACR showed demonstrated symptoms of inflammation in lungs, hypertrophy of bronchiolar epithelium, and hyperplasia of alveolar epithelium. GSH concentration was significantly decreased 3 h after ACR gavage, which was followed by a significant increase 48 h after ACR gavage. Similarly, SOD and GPx demonstrated decreased activities 3 h after exposure to ACR, followed by increased activities 48 h after exposure to ACR. CAT activity was significantly increased 24 and 48 h after exposure to ACR. We conclude that oral exposure of mice to ACR results in alterations of lung microstructure, accompanied by the symptoms of redox imbalance.  相似文献   
388.
Different lipophilicity procedures including a newly developed (based on O?cik's equation) was applied in order to compare various urea pesticides with herbicidal and also insecticidal activity, such as monolinuron, chlorotoluron, diuron, isoproturon, linuron, dimefuron, diflubenzuron, teflubenzuron and lufenuron. Lipophilicity parameters (RMWS and RMW0) of nine examined pesticides were determined on the chromatographic plates RP-8F254 with the use of methanol–water as a mobile phase. Similarity analysis enabled to group all examined pesticides depending on their lipophilic character and allowed to perform a more objective comparison of different lipophilicity parameters obtained for investigated compounds by means of thin-layer chromatography and by the use of computational methods. It was stated that with the number of fluorine in examined pesticides, the lipophilic character of insecticides and also their tendency to bioaccumulation in the living systems increases noticeably. The results of this work confirmed that a new procedure for determining the lipophilicity parameter (RMW0) by O?cik's equation could be a suitable tool in the prediction of pesticide bioaccumulation in living system and may be used as an indicator in design of new urea pesticides, which will be safe for humans and the environment.  相似文献   
389.
The aim of this study was to estimate the health risks associated with consumption of smoked cheeses, which are popular in Poland. The analysis covered polychlorinated biphenyl (PCB) indicator congeners (ndl-PCBs: PCB 28, PCB 52, PCB 101, PCB 138, PCB 153, PCB 180), dioxin-like PCBs (dl-PCBs): non-ortho (PCB 77, PCB 81, PCB 126, PCB 169) and mono-ortho (PCB 105, PCB 114, PCB 118, PCB 156, PCB 157), as well as organochlorine pesticides (OCPs: αHCH, βHCH, γHCH, heptachlor, aldrin, heptachlor epoxid isomer B, dieldrin, pp'DDE op′DDD, pp′DDT, pp′DDD, op′DDT, endrin). The pesticide residues detected in the examined cheese were below the maximum residues levels. The estimated daily intake [lifetime average daily dose (LADD)] referring to the sum of the compounds varied within 4.21·10?7–3.92·10?6 mg·kg?1·day?1 and was significantly lower than the tolerable daily intake/acceptable daily intake (TDI/ADI) for individual compounds. The health hazard quotient, being the exact measure of the magnitude of exposure potential or a quantifiable potential for developing non-carcinogenic health effects after an averaged exposure period, was also very low, ranging from 2.87·10?6 to 5.32·10?5. The obtained results confirmed that the intake of rennet cheese does not pose any consumer health risk in Poland.  相似文献   
390.
Sulfonamides (SAs) are one of the oldest groups of veterinary chemotherapeutic agents. As these compounds are not completely metabolized in animals, a high proportion of the native form is excreted in feces and urine. They are therefore released either directly to the environment in aquacultures and by grazing animals, or indirectly during the application of manure or slurry. Once released into the environment, SAs become distributed among various environmental compartments and may be transported to surface or ground waters. The physicochemical properties of SAs, dosage and nature of the matrix are the factors mainly responsible for their distribution in the natural environment. Although these rather polar compounds have been in use for over half a century, knowledge of their fate and behavior in soil ecosystems is still limited. Therefore, in this work we have determined the sorption potential of sulfadimethoxine and sulfaguanidine on various natural soils. The influence on sorption of external factors, such as ionic strength and pH, were also determined. The sorption coefficients (Kd) obtained for the sulfonamides investigated were quite low (from 0.20 to 381.17 mL g−1 for sulfadimethoxine and from 0.39 to 35.09 mL g−1 for sulfaguanidine), which indicated that these substances are highly mobile and have the potential to run off into surface waters and/or infiltrate ground water. Moreover, the sorption of these pharmaceuticals was found to be influenced by OC, soil solution pH and ionic strength, with higher Kd values for soils of higher OC and lower Kd values with increasing pH and ionic strength.  相似文献   
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