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Certain Trichoderma species are causing serious losses in mushroom production worldwide. Trichoderma aggressivum and Trichoderma pleuroti are among the major causal agents of the green mould diseases affecting Agaricus bisporus and Pleurotus ostreatus, respectively. The genus Trichoderma is well‐known for the production of bioactive secondary metabolites, including peptaibols, which are short, linear peptides containing unusual amino acid residues and being synthesised via non‐ribosomal peptide synthetases (NRPSs). The aim of this study was to get more insight into the peptaibol production of T. aggressivum and T. pleuroti. HPLC/MS‐based methods revealed the production of peptaibols closely related to hypomurocins B by T. aggressivum, while tripleurins representing a new group of 18‐residue peptaibols were identified in T. pleuroti. Putative NRPS genes enabling the biosynthesis of the detected peptaibols could be found in the genomes of both Trichoderma species. In vitro experiments revealed that peptaibols are potential growth inhibitors of mushroom mycelia, and that the host mushrooms may have an influence on the peptaibol profiles of green mould agents.  相似文献   

3.
Appropriate nutrition is a key component of burn treatment and should be regarded as an integral part of the therapeutic process in burn patients. A nutritional intervention plan should not only allow for adequate quantities of energy and protein but also carefully consider the supply of macro- and micronutrients. As a result of the severe inflammatory response, oxidative stress, and hypermetabolic state, accompanied by often extensive exudation in burn patients, there is a considerable loss of macro- and micronutrients, including essential trace elements. This leads to certain complications, involving e.g. more frequent infections and impaired wound healing. Our current body of knowledge is still insufficient, and the studies carried out to date focus for the most part on the imbalances in trace elements, such as copper (Cu), selenium (Se), and zinc (Zn). Nevertheless, there are many other trace elements involved in immune functions, regulating gene expression or antioxidant defense, and many of those have not been properly investigated in a clinical setting. Due to the insufficient amount of unambiguous literature data and relatively few, often dated, studies carried out with small patient groups, further evaluation of macro- and microelements in burn patients seems indispensable, e.g. to bring up to date local nutritional protocols.  相似文献   

4.
This article describes a study in which four trace elements (Se, Mn, Cu, and Fe) were analyzed in the blood serum of the patients with colorectal cancer from the Moravian region of the Czech Republic. Atomic absorption spectrometry with graphite furnace atomization was used for analysis of selenium and manganese and with flame atomization for analysis of copper and iron. The observed serum concentrations in adenocarcinoma colorectal patients of selenium were significantly lower (41.8 ± 11.6 μg/L) and those of manganese (16.3 ± 4.5 μg/L) and iron (2.89 ± 1.23 mg/L) were significantly higher as compared to the age-matched control group. Copper serum content (0.95 ± 0.28 mg/L) did not significantly differ as compared to healthy population.  相似文献   

5.
Chromium (Cr) is of known biological importance, necessary for the maintenance of normal glucose metabolism. There is a lower level of blood Cr concentrations in cases of diabetes. Diabetes carries a risk of cataract development, so the potential effects of Cr on the eye may need to be studied in more depth. The presence of this trace element in both normal and cataractous human lenses has to our knowledge not been investigated so far. The concentration of total Cr in 61 human lenses and 38 blood samples was determined by electrothermal atomic absorption spectrometry with Zeeman effect (EAASZ). Analysis of the levels of Cr in human lenses shows a significant difference between normal and diabetic populations, and an absence of difference between senile and diabetic populations.  相似文献   

6.
The aim of our investigation was to determine the concentrations of Cu, Zn, and Cr in urine samples under routine clinical laboratory conditions. To asses the reliability of these methods, critical factors such as detection limit(s), calibration range(s), cost, accuracy, and precision were studied. Our method was employed for the quantitative determination of zinc, chromium, and copper in urine samples from steel production and quality control (QC) workers and healthy unexposed controls. After pretreatment with acids, the samples were digested via a microwave oven. Zinc was determined by flame absorption spectrophotometry (FAAS), whereas chromium and copper were determined by a graphite-furnace atomic absorption spectrophotometry (GFAAS). Our results indicate that urinary zinc, chromium, and copper levels of the exposed workers are significantly higher than those of the controls. The possibility that these metals are involved in the etiology of diseases is discussed and recommendations are made to improve workplace ventilation and industrial hygiene practices.  相似文献   

7.
Dynamics of manganese,cadmium, and lead in experimental power plant ponds   总被引:2,自引:2,他引:0  
The purpose of this study was to determine the effect of heated power plant water on the uptake and retention of manganese, cadmium and lead in selected aquatic invertebrates, channel catfish, green sunfish, and aquatic macrophytes and to study the distribution of manganese, cadmium and lead in sediments and water of experimental power plant ponds.The study was accomplished by placing fingerling channel catfish and green sunfish in holding pens in two ponds, one an experimental pond and one a control pond. Whole fish and selected organs of channel catfish and green sunfish were analyzed during the study. The experimental pond received heated power plant water and was maintained 4–6° C above ambient temperature during the study. Sediments, water, Odonata nymphs, tubificid annelids, snails, leeches, fingernail clams and duckweed were also analyzed for the metals.A typical distribution profile for manganese, cadmium and lead in power plant cooling ponds was developed.  相似文献   

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9.
This comparative study of the intestinal absorption of four toxic metals (aluminum, manganese, nickel, and lead) carried out in rats using the in situ intestinal perfusion technique was able to measure the partition of each metal between the intestine (intestinal retention), the blood circulation, and target tissues after 1 h. The perfused metal solutions were at concentrations likely to occur during oral intoxication. It was found that aluminum (48 and 64 mM), even as a citrate complex, crossed the brush border with difficulty (0.4% of the perfused amount); about 60% of this was retained in the intestine and the remainder was found in target tissues (about 36%). Conversely, lead (4.8–48 μM) penetrated the intestine more easily (about 35% of the perfused amount), was slightly retained (about 12% of the input), and was soon found in the tissues (about 58% of the input) and to a lesser degree in circulation (about 29%). Within the same concentration range, nickel and manganese showed certain similarities, such as a reduced crossing of the brush border proportional to the increase in the concentration perfused (0.17–9.5 mM). There was similar intestinal retention and absorption (about 80% and 20% of the input, respectively). Manganese crossed the brush border more easily and was diffused more rapidly into tissues. Finally, the addition of equimolar amounts of iron (4.7 mM) produced opposite effects on the absorption of the two elements, inhibiting manganese and showing a trend to increase in nickel absorption. This could be the result of competition between Fe2+ and Mn2+ for the same transcellular transporters and the slight predominance of paracellular mechanism in the event of “Fe2+-Ni2+” association.  相似文献   

10.
ObjectiveAdverse effects of lead exposure on children's health have been demonstrated. While studies have examined the relationship between iron status and low-level lead exposure in children with blood lead levels (BLLs) < 100 μg/L, few have investigated the association between blood lead and other trace elements and anemia in children with BLLs ≥ 100 μg/L. This study aimed to assess the levels of lead, iron, copper, zinc, magnesium, and calcium in children aged 0–14 with BLLs≥ 100 μg/L between 2009 and 2021, and to examine the relationship between blood lead, trace elements and anemia.MethodsA total of 11,541 children with BLLs ≥ 100 μg/L were included in this study. Venous blood samples were collected to measure blood lead levels, hemoglobin levels, and trace element levels. According to the World Health Organization standard, outpatients with hemoglobin levels < 110 g / L were defined as having anemia.ResultsThe study results found that high BLLs and blood calcium had a negative influence on Hb with odds ratios (95% confidence interval) of 1.411(1.208, 1.649) and 1.219(1.043, 1.424). High blood iron had a positive influence on Hb with odds ratios of 0.421(0.355, 0.499).ConclusionThe results suggest that the risk of anemia rose significantly with higher BLLs, blood copper, and blood calcium levels, and decreases considerably with higher blood iron levels.  相似文献   

11.
Cucumber plants grown in hydroponics containing 10 μM Cd(II), Ni(II) and Pb(II), and iron supplied as Fe(III) EDTA or Fe(III) citrate in identical concentrations, were investigated by total-reflection X-ray fluorescence spectrometry with special emphasis on the determination of iron accumulation and distribution within the different plant compartments (root, stem, cotyledon and leaves). The extent of Cd, Ni and Pb accumulation and distribution were also determined. Generally, iron and heavy-metal contaminant accumulation was higher when Fe(III) citrate was used. The accumulation of nickel and lead was higher by about 20% and 100%, respectively, if the iron supply was Fe(III) citrate. The accumulation of Cd was similar. In the case of Fe(III) citrate, the total amounts of Fe taken up were similar in the control and heavy-metal-treated plants (27-31 μmol/plant). Further, the amounts of iron transported from the root towards the shoot of the control, lead- and nickel-contaminated plants were independent of the iron(III) form. Although Fe mobility could be characterized as being low, its distribution within the shoot was not significantly affected by the heavy metals investigated.  相似文献   

12.
Pituitary dwarfism (hGHD) is known to be associated with trace element deficiency, which causes improper functioning of the involved endocrine system. Previously, we reported on the head hair concentrations of zinc, copper, manganese, and iron from a total of 418 normal subjects (154 male and 264 female). In this report, we analyzed the head hair concentrations of the same four trace metals of 103 hGHD children (60 male and 43 female) under treatment with human growth hormone (hGH). These subjects ranged in age from 5 to 18 yr. The results were compared with 338 agematched normal subjects (120 male and 218 female). Both male and female hGHD showed approx 1.7 times higher zinc concentrations than normal subjects. Cheruvanky et al. reported a similar trend but with a slightly lower difference between hGHD and normal subjects. The average copper content in the hair of both male and female subjects also showed higher values for the hGHD than for the normal subjects, a trend similar to the values reported by Teraoka et al. In the case of manganese, the concentrations in hair of the hGHD were approx 50% of the values in the normal subjects. Head hair concentrations of iron in the hGHD were commensurate with the normal subjects. Because the content of trace elements in hair varies with the age of subjects, as a control, we investigated the head hair concentration of zinc from 20 healthy girls ranging in age from 10 to 18 yr. The average zinc concentration decreased from 10 to 12 yr, but no clear relation to age was observed from 13 yr and older. These trends were similar to our previous report. The zinc concentration in hair and body weight gain over a year was negatively correlated. The age variation in the content of zinc, copper, manganese, and iron in hair was measured comparing hGHD with the normal subjects in various ages. Concerning the zinc-level variation of hGHD and normal subjects, there were conspicuous differences between hGHD and normal subjects. For copper, the variations in concentration with age were similar to zinc. Regarding the age variations for manganese, hGHD had lower concentrations in hair compared to the normal subjects throughout adolescence (11–18 yr). We have studied the effects between the hair and these trace element concentrations in hGHD before and after hGH administration. These results suggest that hGH affects the metabolism of these trace elements.  相似文献   

13.
Total aluminum, chromium, copper, iron, manganese, and nickel were determined in black tea, green tea, Hibiscus sabdariffa, and Ilex paraguariensis (mate) by electrothermal atomic absorption spectrometry after nitric/perchloric acid digestion. In each case, one ground sample of commercially available leafy material was prepared and three 0.5-g subsamples were run in parallel. The infusions were also analyzed and the percentage of each element leached into the liquor was evaluated. The obtained results indicated that hibiscus and mate contained lower levels of aluminum (272±19 μg/g and 369±22 μg/g, respectively) as referred to black tea (759±31 μg/g) or green tea (919±29 μg/g) and suggested that mate drinking could be a good dietary source of essential micronutrient manganese (total content 2223±110 μg/g, 48.1% leached to the infusion). It was also found that the infusion of hibiscus could supply greater amounts of iron (111±5 μg/g total, 40.5% leached) and copper (5.9±0.3 μg/g total, 93.4% leached) as compared to other infusions. Moreover, it was found that the percentage of element leached to the infusion was strongly related to the tannins content in the beverage (correlation coefficients >0.82 with the exception for nickel); for lower tannins level, better leaching was observed.  相似文献   

14.
Summary The inhibition of the respiration rate by the heavy metals, Cd, Cr, Cu, Pb, Ni and Zn was investigated in five Dutch soil types in relation to the length of time these heavy metals were present in the soil. The amounts of heavy metal added as chloride salts to the soils were 0, 55, 150, 400, 1000, 3000 and 8000 g·g–1, respectively. The measurements were carried out both immediately after the addition of the heavy metals and approximately 18 months later. The inhibition during the first two to eight weeks was not obscured by an extra nutrient flush to drying. During the 18 months, the toxicity decreased but was still significant. Inhibition was greatest in the sandy soil and least in the clay soil. In a loam soil and in a sandy peat soil, the inhibiting effects were intermediate, but distinct. The main abiotic factors responsible for these different degrees of inhibition were the clay fraction for Cd, the Fe content for Cu, Pb and Zn and the pH for Ni. Although clay, Fe, and Mn together with the organic matter fraction, determine the total cation exchange capacity of soil, their contribution to the toxicity of heavy metals may be antagonistic. The latter may increase the mobility due to chelation and therefore possibly increase the toxicity, while the other factors may bind the heavy metals and therefore decrease the toxicity.  相似文献   

15.
Poplar (Populus jacquemontiana var. glauca cv. Kopeczkii) was grown in hydroponics containing 10 μM Cd(II), Ni(II) or Pb(II), and Fe as Fe(III) EDTA or Fe(III) citrate in identical concentrations. The present study was designed to compare the accumulation and distribution of Fe, Cd, Ni and Pb within the different plant compartments. Generally, Fe and heavy-metal accumulation were higher by factor 2-7 and 1.6-3.3, respectively, when Fe(III) citrate was used. Iron transport towards the shoot depended on the Fe(III) chelate and, generally, on the heavy metal used. Lead was accumulated only in the root. The amounts of Fe and heavy metals accumulated by poplar were very similar to those of cucumber grown in an identical way, indicating strong Fe uptake regulation of these two Strategy I plants: a cultivar and a woody plant. The Strategy I Fe uptake mechanism (i.e. reducing Fe(III) followed by Fe(II) uptake), together with the Fe(III) chelate form in the nutrient solution had significant effects on Fe and heavy metal uptake. Poplar appears to show phytoremediation potential for Cd and Ni, as their transport towards the shoot was characterized by 51-54% and 26-48% depending on the Fe(III) supply in the nutrient solution.  相似文献   

16.
Abstract

Total mercury (Hg) concentrations were assessed during July 2017 in two commercial fish species Pimelodus maculatus and Calophysus macropterus from two locations of Acre river (Acre State, Brazilian Amazon) - Iñapari (undeveloped areas) and Assis Brazil (urban areas). The current study aimed to assess: (i) Hg spatial variations; (ii) the assimilation efficiencies in different tissues and (iii) the ecological quality of these ecosystems based on tissue Hg concentrations. Both species showed significantly (p?<?.05) different Hg concentrations between tissues. Hg concentrations were significantly higher than those previously reported for these Amazon regions. Hg concentrations in Assis Brazil were significantly higher (p?<?.05) than in Iñapari, indicating an anthropogenic influence. Bioaccumulation factors indicated that kidney and liver are the main Hg retention tissues. Considering European and Brazilian mercury guidelines in foodstuff, Iñapari and Assis Brazil are “Unpolluted” during July 2017, although hepatic Hg concentrations in C. macropterus from Assis Brazil showed evidences of anthropogenic contamination.  相似文献   

17.
The balances and content of essential elements (iron, copper, zinc, chromium and manganese) in the body of Wistar, Zucker lean and Zucker obese rats fed a reference or cafeteria diet from day 30 to 60 after birth have been studied. Intestinal iron absorption compensated for low iron content of the cafeteria diet and the extra needs of growth and fat deposition. It can be assumed that the altered energy regulation processes that afflict the genetically obese rat are not directly related to altered iron metabolism. Obese Zucker rats had lower copper tissue concentrations than lean rats, but when fed a cafeteria diet the differences between Zucker rats strains disappear. This cannot be traced to large differences in diet copper concentration. A low diet availability of zinc—such as that of cafeteria-fed fa/fa rats—is easily compensated for by increasing absorption. So, as a consequence, we can conclude that genetic obesity did not impair zinc absorption. There was no deficit of zinc in any of the groups studied; the rats have enough capacity to extract zinc within a wide range of dietary concentrations. The absorption of dietary chromium was inversely proportional to its concentration. The ability to extract chromium from the diet and the very low urinary losses are a consequence of its scarcity in most dietary items. Despite wide variations in the manganese of the diets, the absorption rates were practically unchanged except for obese rats fed the cafeteria diet. It seems that this low absorptive capacity is enough to supply the rat with the manganese it needs, since a sizeable—but subjected to 8-fold-span variations-proportion is lost in the urine. This alone points towards a considerable excess of manganese in both diets studied. Obesity does not have a significant effect on the abilities to absorb and retain minerals, since these processes were more related to dietary availability. Management of essential metals by obese rats depends whether this condition is genetic or induced by diet. Most of the differences observed can be related to differences in diet concentration, to the excess fat content or different metabolic attitude to use substrates of obese animals. The data presented show that the cafeteria diet used adequately serves the mineral needs of the rat, since the rat adapts its absorbing and retaining strategies to match the dietary availability of these minerals.  相似文献   

18.
The sheep tapeworm (Moniezia expansa) and its host Ovis aries were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES) for their copper, iron, manganese, zinc and lead levels. Element concentrations in cestode parasites were compared to those in various organs (liver, kidney, and muscle) of sheep. Tapeworms in the small intestine of sheep that were administered 2g of Pb(CH(3)COO)(2) per os daily (7 days) had significantly higher lead concentrations than sheep tissues. Cu levels significantly increased after Pb administration in sheep muscle and sheep tapeworms. Contrarily, Zn content significantly decreased in sheep muscle, but significantly increased in sheep tapeworms. However, Mn content significantly decreased after Pb administration in sheep tapeworms. Furthermore, Fe content significantly decreased after Pb administration in sheep liver and kidneys.  相似文献   

19.
通过室内模拟实验,研究了孔石莼和重金属(铜、镉、锌和铅)共同作用下,海水无机碳体系及碳源汇格局的变化.结果表明,t=7d时,无机碳体系各参数的变化幅度(Δ)与重金属种类和浓度有关.与对照相比,低浓度(<1μmol · L-1)的重金属添加组中,DIC、HCO-3 和PCO2的下降幅度都很明显(P<0.01* *).当铜、镉浓度大于"转折浓度"后, DIC、HCO-3和Pco2 均要大于初始值,其增幅随着重金属浓度的增加而增大.对于锌和铅,二者浓度高达50μmol · L-1时,水体中无机碳各参数与初始值相比仍呈现下降趋势.此外,当重金属浓度和种类不同时,水体中的碳源汇格局亦做不同的变化.当铜和镉浓度小于转折浓度时,水体表现为大气CO2的汇;而当铜和镉超出转折浓度时,水体会由大气CO2的汇过渡到源,并且当水体成为CO2的源后,其CO2的释放量是随着铜、镉浓度的增加而增大.在本实验设计的各浓度锌、铅添加组水体始终表现为碳汇,但当锌、铅浓度分别高于15μmol · L-1和20μmol · L-1时,其碳汇强度开始小于对照组(P<0.05*).  相似文献   

20.
Miniscrews are used as orthodontic anchorage devices in the dentistry clinical practice but the in vivo metallic release from these structures has been not previously investigated. The aim of this study was to determine the content of Al, Co, Cr, Cu, Ni, Ti and V in oral mucosa cells of control subjects, patients under orthodontic treatment and with both, orthodontic treatment and miniscrew, in order to know the contribution of these mini-implants to the total metallic content. ICP-MS measurements revealed the following ascending order: Cr < Ni < Ti < Cu < Al, and Co and V were practically undetected. Significant differences in comparison to the control group were found for Cu in the orthodontic group, and for Ni in both, orthodontic and orthodontic + miniscrew groups. Potential correlations among metallic elements and with some clinical factors were also explored. These findings suggest that miniscrews do not increase significantly the metal release.  相似文献   

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