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1.
Summary The uptake of trace metals by two plant species (French bean and maize) has been measured on two soils subjected to various waterlogging regimes. Uptake of both manganese and iron was increased due to soil waterlogging, although reoxidation of the soil affected iron more than manganese. Zinc and copper uptake was influenced by a species factor; French bean (Phaseolus vulgaris) showed preferential uptake of zinc, whereas maize (Zea mays) took up copper preferentially. Uptake of cobalt by both species was increased due to waterlogging, following the pattern of manganese.The abilities of these species to take up trace metals from soil followed the pattern predicted by selective extraction of soil for manganese, iron and cobalt, but not for zinc and copper.  相似文献   

2.
BackgroundThe existing data demonstrate the potential role of trace elements in nasal mucociliary clearance, although the association between trace element and mineral status and ciliary function in children with chronic rhinosinusitis is insufficiently studied. Therefore, the objective of the present study is evaluation of trace element and mineral status and mucociliary function in pediatric CRS patients before and after functional endoscopic sinus surgery.MethodsThe present study involved 30 children with chronic rhinosinusitis without nasal polyps. During this follow-up the patients were examined preoperatively (point 0), underwent functional endoscopic sinus surgery, and were repeatedly examined at three months postoperatively (point 1). At both points the patients were subjected to quality-of-life assessment using SNOT-20 questionnaire; endoscopic and computer tomography examination of the nasal sinuses; evaluation of ciliary function and mucosal cytology using high-speed videomicroscopy; assessment of blood count and inflammatory markers; as well as analysis of trace element and mineral levels in whole blood, serum, and hair using inductively-coupled plasma mass-spectrometry.ResultsThe obtained data demonstrate that endoscopic sinus surgery significantly improved sinonasal pathology in children with chronic rhinosinusitis, as evidenced by significantly reduced Lund-Mackay, Lund-Kennedy, and SNOT-20 scores. At the same time, no significant improvement of ciliary functions or mucosal cytology was observed postoperatively. Trace element status assessment demonstrated that postoperative serum Zn, whole blood Mg and Cu were significantly lower as compared to preoperative values. In contrast, serum Mn and Cr, as well as whole blood Cr and hair Se were characterized by a significant increase at three months postoperatively. Multiple linear regression analysis demonstrated that serum Zn is significantly associated with the number of ciliated cells and cell viability, whereas serum Mn and whole blood Cu concentrations are inversely associated with cell viability and ciliary length, respectively. Hair Se was found to be associated with the number of neutrophils in the mucosa biopsy.ConclusionRedistribution of trace elements and minerals may at least partially mediate prolonged recovery of mucosal ciliary function in children with chronic rhinosinusitis in three months after functional sinus surgery, although the particular mechanisms of these alterations in trace element levels are to be discovered.  相似文献   

3.
The present study was conducted during 2005 and 2006 on 200 Nili-Ravi buffaloes kept in two agroecological zones (irrigated [zone 1] and rain-fed [zone-2]) of Punjab, Pakistan, with the objective to determine the level of trace minerals (Cu, Fe, Zn, Se) in serum of the buffaloes suffering from vaginal prolapse and to compare them with their healthy counterparts. In each zone 50 buffaloes suffering from prepartum vaginal prolapse during their seventh month of gestation were identified through survey. Vaginal prolapse-affected buffaloes belonging to zone 1 were identified as group VPB1 (N = 50), whereas buffaloes belonging to zone 2 were recognized as VPB2 (N = 50). The buffaloes of control group in zone 1 and zone 2 were identified as NCB1 and NCB2, respectively. The blood samples in all four groups of buffaloes were collected three times, i.e., first when these animals were in the eighth month of gestation, second during the eighth to ninth month of gestation, and finally when these animals were in the ninth or later month of gestation. The mean serum copper concentrations in buffaloes of group VPB1 were significantly lower (P < 0.05) in comparison with NCB1 and NCB2, whereas there were nonsignificant differences (P > 0.05) in copper concentrations between VPB1 and VPB2. There was a significant difference (P < 0.05) of iron concentration in VPB1 compared with NCB1 and NCB2. Similarly, VPB2 also had significantly lower (P < 0.05) iron concentrations compared with NCB1 and NCB2. Serum zinc concentrations were significantly lower (P < 0.05) in animals of the VPB1 group when compared with NCB1 and NCB2. Similarly, lower zinc concentrations were observed in VPB2 in comparison with NCB1 and NCB2. There was significantly lower (P < 0.05) zinc concentration in affected buffaloes (VPB1 and VPB2) from the ninth month of gestation to term when compared with those in the eighth to ninth mo of gestation, and with those not yet in the eighth month of gestation. Serum selenium concentration were significantly higher (P < 0.05) in control group buffaloes (NCB1 and NCB2) in comparison with vaginal prolapse-affected buffaloes (VPB1 and VPB2). During different stages of gestation, mean serum selenium concentrations varied nonsignificantly (P > 0.05) within each group of buffalo. Based on information obtained from this study, it was concluded that the low serum concentration of copper and selenium are linked to increased incidence of vaginal prolapse in buffaloes during the last trimester of gestation.  相似文献   

4.
Summary The effects of four Zn levels on the electrochemical and chemical properties of the soil solution, and on the growth and mineral nutrition of two rice varieties (IR26 and IR34) differing in tolerance to Zn deficiency were studied in the greenhouse using Zn-deficient soils from two locations. A similar experiment was conducted in culture solution to check how Zn addition affects translocation of other nutrients.In both soil and culture solution, plant Zn concentrations alone was not enough to account for varietal tolerance to Zn deficiency. Comparison of nutrient to Zn and shoot to root ratios of nutrients was more useful in determining the possible mechanism of varietal tolerance. IR 34 appeared to tolerate the disorder due to its lower Zn requirement, more efficient Zn translocation and ability to maintain lower Fe/Zn, Cu/Zn, Mg/Zn and P/Zn ratios in the shoot than the more susceptible variety, IR26. This was shown to be due to decreased translocation of Fe, Mg and P to shoots and decreased absorption of Cu by the root in IR34 in culture solution studies. Adding Zn further reduces translocation or absorption of these nutrients and depending on the nutrient supply of the soil, could cause deficiencies or mineral imbalances, especially of Fe, Cu, and P.These observed varietal differences regarding Zn requirement and the interaction of Zn with absorption and translocation of plant nutrients necessitates revision of recommendations for Zn fertilization. There is an inevitable need for Zn application in severely Zn-deficient soils regardless of rice variety. But on marginally Zn-deficient soils especially those low in Fe, Cu, or P, Zn fertilization is not advisable when resistant rice varieties are used.  相似文献   

5.
Background Trace elements are involved in many key pathways involving cell cycle control. The levels of trace metals such as iron, copper, and zinc in colorectal liver metastases have not previously been assessed. Methods The trace element content in snap-frozen cancerous liver tissue from patients who underwent liver resection for colorectal liver metastases was compared with the normal surrounding liver (distant from the cancer) using X-ray fluorescence (XRF). Results X-ray fluorescence was performed on a total of 60 samples from 30 patients. Of these 29 matched pairs (of cancer and normal liver distant from cancer from the same patient) were eligible for univariate analysis. Iron (0.00598 vs. 0.02306), copper (0.00541 vs. 0.00786) and zinc (0.01790 vs. 0.04873) were statistically significantly lower in the cancer tissue than the normal liver. Iron, copper, and zinc were lower in the cancer tissue than in the normal liver in 24/29 (82.8%), 23/29 (79.3%), and 28/29 (96.6%) of cases respectively. Multivariate analysis of the 60 samples revealed that zinc was the only trace element decreased in the cancer tissue after adjusting for the other elements. Zinc levels were not affected by any of the histopathological variables. Conclusion Iron, copper, and zinc are lower in colorectal liver metastases than normal liver. An investigation into the pathways underlying these differences may provide a new understanding of cancer development and possible novel therapeutic targets.  相似文献   

6.
Quinone profiles and physico-chemical properties were measured to characterize the microbial community structure during a 14-day thermophilic composting of cattle manure mixed with rice straw as a bulking agent. The change in total quinone content (TQ) and the divergence of quinone (DQ) indicated that the microbial biomass reached a peak followed by a decrease, whereas the microbial community diversity increased continuously during the composting process. The high mole fraction of ubiquinones in the raw materials, and at the beginning of the composting period suggested that fungi and/or Proteobacteria were present. The predominance of MK-7 from days 3 to 7 suggested that Bacillus spp. were the main microbial species. An increase in partially saturated and long-chain menaquinones during the latter composting period indicated that the proliferation of various species of Actinobacteria was occurring. The microbial community structure, as expressed by TQ and DQ, corresponded well to physico-chemical properties such as the C/N ratio, pH, O2 consumption and compost mass reduction.  相似文献   

7.
Summary The influence of heavy metal additions on availability and uptake of cadmium, lead, zinc, copper, manganese and iron by oat was studied. The experiments were carried out as pot experiments using sandy loam, sandy soil and organic soil. Selective extractants were used to remove metals held in different soil fractions.Lead and copper were preferently bound by organics and oxides, zinc by oxides and inorganics, and cadmium by inorganics and organics.Addition of cadmium to the soils resulted in higher cadmium concentrations in all plant parts but lower concentrations of lead, zinc, copper, manganese and iron, and the accumulation indexes of these metals were also lower when cadmium was added to the soil.Addition of cadmium plus lead, zinc and copper resulted in higher cadmium concentrations in leaves and straw of plants grown in sandy loam and sandy soil, but lower concentrations when plants were grown in organic soil as compared with the results when cadmium was added separately. The transfer of cadmium, lead, zinc and copper from soil to plant was greatest from sandy soil, and zinc and cadmium were more mobile in the plant than were lead and copper.Cadmium concentrations in leaves correlated significantly with CaCl2 and CH3COOH extractions in sandy loam and sandy soil and with CH3COOH extractions in organic soil.Generally, the total metal uptake was lowest from organic soil.  相似文献   

8.
Summary An ion exchange and chelating resin system was developed to buffer the activities of selected free cations and phosphate in hydroponic solutions at concentrations similar to those that occur naturally in soil solutions. Free-ion activities of Cd, Cu, Ni, Zn, Mn, H, Ca, Mg, and K were maintained by ion exchange and chelating resins in a controlled ionic strength system. Iron was controlled by EDDHA and chelating resin, and P by a cation-exchange resin containing adsorbed polynuclear hydroxyaluminum. This mixed-resin hydroponic system was used to establish a range of ionic Cd activities similar to that found in soil solutions of soils amended with sewage sludge. Activities of other nutrients were maintained at realistic soil-solution levels. A metal complexing agent (EDTA) was used to increase total metal concentration in the hydroponic solutions without significantly altering the ionic activities of the metals maintained in solution. This allowed differentiation of the effects of free ions and complexed metals on metal uptake. Concentrations of metal complexes in solution were controlled by the ion activities of the metals maintained and the concentrations and selectivities of the complexing agent. The mixed-resin system supplied sufficient nutrients for the growth of tomato plants (Lycopersicon esculentum, cv. Wisconsin-55) in hydroponic culture. Research supported by the College of Agricultural and Life Sciences, University of Wisonsin-Madison and by United States Environmental Protection Agency through Grant CR807270010.  相似文献   

9.
Response to acute nickel toxicity in rats as a function of sex   总被引:1,自引:0,他引:1  
Summary The effects of different nickel chloride doses upon blood and plasma glucose and essential metal homeostasis were studied in male and female rats. A definite sex-dependent response to injections of nickel has been observed for both the increase in plasma and blood glucose levels and the time at which these levels peak. Males showed a fast recovery from the rise in glucose levels and were much less affected by changes in the other parameters studied. In females, an extended rise in glucose levels was observed. All these effects are clearly nickel dose-dependent. Plasma, liver and kidney copper levels rose significantly in females while only a small decrease was observed in male kidneys. Zinc levels rose in all organs studied but males recovered to basal levels after the study period, whereas females maintained maximum levels at the end of the same period. An increase in urinary excretion of iron was observed. The present results show that the sex differences to acute nickel toxicity can be a helpful way to study metal interaction and discriminate between specific toxicity due to nickel or that induced by the associated hyperglucagonemia.  相似文献   

10.
Abstract The technique of differential pulse polarography is shown here for the first time to be applicable to monitoring directly the uptake of metal ions from solution by live bacteria in the chamber of the polarograph. The potential at which the polarographic current peak is observed is characteristic of the metal, whereas peak height is proportional to metal concentration. Adding solutions of Cd(II) or Zn(II) to a suspension of Pseudomonas cepacia in 50 mM Hepes buffer (pH 7.4) in the chamber gave polarographic peaks of lower amplitude than those observed when these metal solutions were added to buffer alone, due to metal binding or uptake by cells. Langmuir plots gave binding capacities of 0.13 and 0.20 mmol metal (Dd or Zn, respectively) per g (dry weight) biomass. Ni(II) uptake was biphasic. Metal uptake increased with pH. The value of polarography for rapid assessment of metal removal by cells and the ability to measure uptake from multi-metal solutions is demonstrated.  相似文献   

11.
BackgroundTo this day, empirical data suggests that zinc has important roles in matrix synthesis, bone turnover, and mineralization and its beneficial effects on bone could be mediated through different mechanisms. The influence of zinc on bone turnover could be facilitated via regulating RANKL/RANK/OPG pathway in bone tissue. Therefore, the aim of the study was to conduct a review to investigate the possible effect of the zinc mediated bone remodeling via RANKL/RANK/OPG pathway.MethodsA comprehensive systematic search was performed in MEDLINE/PubMed, Cochrane Library, SCOPUS, and Google Scholar to explore the studies investigating the effect of zinc as a bone remodeling factor via RANKL/RANK/OPG pathway regulation. Subsequently, the details of the pathway and the impact of zinc supplements on RANKL/RANK/OPG pathway regulation were discussed.ResultsThe pathway could play an important role in bone remodeling and any imbalance between RANKL/RANK/OPG components could lead to extreme bone resorption. Although the outcomes of some studies are equivocal, it is evident that zinc possesses protective properties against bone loss by regulating the RANKL/RANK/OPG pathway. There are several experiments where zinc supplementation resulted in upregulation of OPG expression or decreases RANKL level. However, the results of some studies oppose this.ConclusionIt is likely that sufficient zinc intake will elicit positive effects on bone health by RANKL/RANK/OPG regulation. Although the outcomes of a few studies are equivocal, it seems that zinc can exert the protective properties against bone loss by suppressing osteoclastogenesis via downregulation of RANKL/RANK. Additionally, there are several experiments where zinc supplementation resulted in upregulation of OPG expression. However, the results of limited studies oppose this. Therefore, aside from the positive role zinc possesses in preserving bone mass, further effects of zinc in RANKL/RANK/OPG system requires further animal/human studies.  相似文献   

12.
The synthesis of metallothioneins (MTs) is often induced when organisms are exposed to heavy metals in the field. They are among the major "specific" biomarkers identified to date. With a view to include MTs in biomonitoring programs, the organisms most commonly studied are bivalves. Sponges present most of the characteristics researched in bioindicators of pollution and consequently have been proposed to constitute a "Sponge Watch Program". The detection of large quantities of metals in sponges suggests the existence of detoxification systems and indeed, the presence of metallothionein-like proteins (MTLPs) has been reported in two different species of sponges. In Spongia officinalis, the present study has demonstrated the presence of compounds exhibiting most of the characteristics of MTs: cytosolic, heat-stable, with apparent molecular mass of 4 to 15 kDa and binding (at least) Ag, Cu and Zn. Specimens have been collected along the French Mediterranean coast from three sites differing by their degree of contamination. Relationships between MTLP and metal concentrations have been established. For copper, mercury and zinc, the correlations were significantly positive.  相似文献   

13.
Crabs, Pachygrapsus marmoratus, were sampled in June 1997 and February 1998 from two sites (at the mouth and 25 km upstream) in the metal-rich Gironde estuary, France. Gills and hepatopancreas were analysed for metal (Cd, Cu, Zn) and metallothionein (MT) contents, in order to examine the influence of both biological and environmental factors on the physico-chemical forms of detoxified metal storage in the crabs. The concentrations of MT and both cytosolic and insoluble metals were not greatly different between males and females, and the influence of organ weights was also minimal. Intersite differences were observed, probably resulting from the gradient of salinity in the estuary, which interacts with both the chemical speciation and bioavailability of metals, and the general protein metabolism of the crabs. Seasonal changes were also important, probably in interaction with the moult and reproductive cycles. In February, concentrations of insoluble metals were generally higher than in June, in both organs, suggesting that essential metals, particularly Zn, are stored during winter then remobilised during the breeding season. The natural variability in the concentrations of MT often concealed any relationship with accumulated metal concentrations. Thus MT in crabs cannot be considered as a useful biomarker of metal pollution.  相似文献   

14.
The aim of the study was to determine the relative bioavailability of zinc gluconate stabilized with glycine in a Petit Suisse cheese from an infant dessert. Weight gain and bone zinc content were the nutritional responses evaluated for the diets of different zinc content: 2 ppm (basal) and 5, 10, and 30 ppm from zinc gluconate stabilized with glycine and zinc sulfate. Nonlinear regression analysis of the fitted curves for weight gain determined a relative zinc bioavailability of 100% for the Y max ratio and 96% for Y max/t 1/2 ratio for zinc gluconate stabilized with glycine (R 2=0.7996 for zinc sulfate and 0.8665 for zinc gluconate stabilized with glycine). The slope ratio analysis from linear regression of femur zinc determined a relative zinc bioavailability of 93% for zinc gluconate stabilized with glycine (R 2=0.8693 for zinc sulfate and 0.8307 for zinc gluconate stabilized with glycine). Zinc gluconate stabilized with glycine has similar bioavailability as zinc sulfate in a Petit Suisse cheese nutritional matrix, with the advantage that the stabilized compound does not modify the sensorial characteristics of the fortified cheese.  相似文献   

15.
Summary Cucumber (Cucumis sativus) plants were grown in Hoagland solution to which 20 to 2000 ppm of a soil fulvic acid (FA) were added. The addition of 100 to 300 ppm of FA produced highly significant increases in the growth and development of above and below ground plant parts, in the uptake of nutrient elements (N, P, K, Ca, Mg, Cu, Fe and Zn), and in the formation of numbers of flowers per plant. Effects of adding 500 and more ppm of FA were less beneficial.  相似文献   

16.
An easily performed, specific, sensitive, rapid, reliable and inexpensive procedure for the spectrofluorometric quantitation of ascorbic acid was proposed using acriflavine as a fluorescence quenching reagent. The procedure was based on the determined quenching effect of ascorbic acid on the natural fluorescence signal of acriflavine and the reaction between ascorbic acid and acriflavine in Britton–Robinson buffer solution (pH 6) to produce an ion‐associated complex. The reduction in acriflavine fluorescence intensity was detected at 505 nm, while excitation occurred at 265 nm. The relationship between quenching fluorescence intensity (?F) and concentration of ascorbic acid was linear (R2 = 0.9967) within the range 2–10 μg/ml and with a detection limit of 0.08 μg/ml. No significant interference was detected from other materials often found in pharmaceutical nutritional tablets. The obtained results were compared with those from high‐performance liquid chromatography and appeared in good agreement, with no important differences in precision or accuracy. The proposed spectrofluorimetric method was used to determine the amount of ascorbic acid in a number of commercial pharmaceutical nutritional supplement tablets with a 95% confidence performance.  相似文献   

17.
The present work proposes the use of Pleurotus ostreatus immobilized on Amberlite XAD-4 as new biosorbent in trace metal determination. The effects of experimental parameters, such as “pH and flow rate of sample solution, amount of solid phase, eluent type, and concentration” on the recovery of the metal ions were investigated. Maximum adsorption of Cr(III), Cd(II) and Cu(II) ions took place in the pH range 4-5. These metal ions can be desorbed with 1 M HCl (recovery 95-100%). 0.2 g adsorbent amount and 2.5 mL min−1 flow rate was found to be optimum of all preconcentration experiments. The sorption capacity after 10 cycles of sorption and desorption does not vary more than 2.0%. The influences of the contaminant ions on the retentions of the analytes were also examined. The results showed that P. ostreatus immobilized on Amberlite XAD-4 can be considered as very promising material in trace metal determination.  相似文献   

18.
The ozone in an air sample was trapped by H3BO3‐LK solution to produce iodine (I2) that interacted with excess I to form I3. In pH 4.0 acetate buffer solutions, the I3 reacted with acridine red to form acridine red–I3 ion association particles that resulted in the fluorescence peak decreased at 553 nm. The decreased value ΔF553 nm is linear to the O3 concentration in the range 0.08–53.3 × 10–6 mol/L, with a detection limit of 4 × 10–8 mol/L. This fluorescence method was used to determine ozone in air samples, and the results were in agreement with that of indigo carmine spectrophotometry. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

19.
Smith  Steven  Kwan  Michael K. H. 《Hydrobiologia》1989,188(1):345-351
Floating aquatic macrophytes such as the Lemnaceae have many attributes which commend their use in laboratory and field investigations to assess both the toxicity of substances and the quality of freshwater systems. As well as their more well known advantages of small size, relative structural simplicity, rapid growth and vegetative reproduction and genetically homogenous populations, they are also excellent accumulators of a number of metallic elements. This raises the possibility of the use of these aquatic macrophytes in water quality monitoring and also as laboratory bioassays for toxicity and uptake studies. Results are presented of a study of the comparative toxicity, uptake kinetics and accumulated forms of thallium and cadmium in the duckweed, Lemna minor and the role of this methodology in water quality monitoring and hazard evaluation are discussed.  相似文献   

20.
Indirect survey methods are often used in studies of mammals but are susceptible to biases caused by failure to detect species where they are present. Occupancy analysis is an analytical technique which enables non‐detection rates to be estimated and which can be used to develop and refine novel survey methods. In this study, we investigated the use of footprint tunnels by volunteers as a method for surveying occupancy of sites by hedgehogs Erinaceus europaeus. The survey protocol led to a very low non‐detection rate and could reasonably be used to detect occupancy changes of 25% with statistical power of 0.95 in a national survey.  相似文献   

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