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101.
N. Haque J.R. Peralta-Videa M. Duarte-Gardea J.L. Gardea-Torresdey 《Bioresource technology》2009,100(24):6177-6182
The selection of appropriate seeds is essential for the success of phytoremediation/restoration projects. In this research, the growth and elements uptake by the offspring of mesquite plants (Prosopis sp.) grown in a copper mine tailing (site seeds, SS) and plants derived from vendor seeds (VS) was investigated. Plants were grown in a modified Hoagland solution containing a mixture of Cu, Mo, Zn, As(III) and Cr(VI) at 0, 1, 5 and 10 mg L−1 each. After one week, plants were harvested and the concentration of elements was determined by using ICP-OES. At 1 mg L−1, plants originated from SS grew faster and longer than control plants (0 mg L−1); whereas plants grown from VS had opposite response. At 5 mg L−1, 50% of the plants grown from VS did not survive, while plants grown from SS had no toxicity effects on growth. Finally, plants grown from VS did not survive at 10 mg L−1 treatment, whilst 50% of the plants grown from SS survived. The ICP-OES data demonstrated that at 1 mg L−1 the concentration of all elements in SS plants was significantly higher compared to control plants and VS plants. While at 5 mg L−1, the shoots of SS plants had significantly more Cu, Mo, As, and Cr. The results suggest that SS could be a better source of plants intended to be used for phytoremediation of soil impacted with Cu, Mo, Zn, As and Cr. 相似文献
102.
Odile?Sergent Aldo?Tomasi Daniela?Ceccarelli Alberto?Masini Hans?Nohl Pierre?Cillard Josiane?Cillard Yuri?A.?Vladimirov Andrey?V.?KozlovEmail author 《Biometals》2005,18(6):567-575
Iron overload aggravates tissue damage caused by ischemia and ethanol intoxication. The underlying mechanisms of this phenomenon
are not yet clear. To clarify these mechanisms we followed free iron (“loosely” bound redox-active iron) concentration in
livers from rats subjected to experimental iron overload, acute ethanol intoxication, and ex vivo warm ischemia. The levels of free iron in non-homogenized liver tissues, liver homogenates, and hepatocyte cultures were
analyzed by means of EPR spectroscopy. Ischemia gradually increased the levels of endogenous free iron in liver tissues and
in liver homogenates. The increase was accompanied by the accumulation of lipid peroxidation products. Iron overload alone,
known to increase significantly the total tissue iron, did not affect either free iron levels or lipid peroxidation. Homogenization
of iron-loaded livers, however, resulted in the release of a significant portion of free iron from endogenous depositories.
Acute ethanol intoxication increased free iron levels in liver tissue and diminished the portion of free iron releasing during
homogenization. Similarly to liver tissue, the primary hepatocyte culture loaded with iron in vitro released significantly more free iron during homogenization compared to non iron-loaded hepatocyte culture. Analyzing three
possible sources of free iron release under these experimental conditions in liver cells, namely ferritin, intracellular transferrin-receptor
complex and heme oxygenase, we suggest that redox active free iron is released from ferritin under ischemic conditions whereas
ethanol and homogenization facilitate the release of iron from endosomes containing transferrin-receptor complexes. 相似文献
103.
Migita K Lu L Zhao Y Honda K Iwamoto T Kita S Katsuragi T 《Biochemical and biophysical research communications》2005,328(4):1211-1215
ATP is released into extracellular space as an autocrine/paracrine molecule by mechanical stress and pharmacological-receptor activation. Released ATP is partly metabolized by ectoenzymes to adenosine. In the present study, we found that adenosine causes ATP release in Madin-Darby canine kidney cells. This release was completely inhibited by CPT (an A1 receptor antagonist), U-73122 (a phospholipase C inhibitor), 2-APB (an inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) receptor blocker), thapsigargin (a Ca2+-ATPase inhibitor), and BAPTA/AM (an intracellular Ca2+ chelator), but not by DMPX (an A2 receptor antagonist). However, forskolin, epinephrine, and isoproterenol, inducers of cAMP accumulation, failed to release ATP. Adenosine increased intracellular Ca2+ concentrations that were strongly blocked by CPT, U-73122, 2-APB, and thapsigargin. Moreover, adenosine enhanced accumulations of Ins(1,4,5)P3 that were significantly reduced by U-73122 and CPT. These data suggest that adenosine induces the release of ATP by activating an Ins(1,4,5)P3 sensitive-Ca2+ pathway through the stimulation of A1 receptors. 相似文献
104.
Hilary Glover 《Journal of phycology》1977,13(3):208-212
Cultures of Isochrysis galbana Parks and Phaeodactylum tricornutum Bohlin were grown in iron-limited chemostats. With increasing iron deficiency, photosynthetic rate per cell and assimilation number decreased. The pattern of photosynthesis was also altered; in Fe deficient cells the proportion of 14C fixed in glycine and serine decreased with an accompanying increase into alanine after 3 min assimilation. Although there was no significant effect of Fe deficiency on the proportion of 14C incorporated into total amino acids and amides, the percentage of total 14C fixed in protein increased with increasing Fe deficiency. Cellular levels of chlorophyll a, carotenoids, cytochromes and protein also decreased with increasing Fe deficiency. However, the reduction in chlorophyll a/cell was not as great as that of cytochrorne f1 and Fe deficient cells therefore showed a marked increase in chlorophyll a:cytochrorne f1 ratio. 相似文献
105.
106.
107.
斜纹夜幼虫对食物中重金属Ni2+的积累与排泄 总被引:2,自引:0,他引:2
为明确食物中重金属离子在昆虫体内的分布和转移情况,本文采用等离子体原子发射光谱仪检测了植食性昆虫斜纹夜蛾Spodoptera litura Fabricius连续3个世代6龄幼虫对食物中过量Ni2+的排泄和积累情况。结果表明:大部分Ni2+可通过粪便排出体外;沉积在体内的Ni2+主要积累在中肠,部分Ni2+可通过中肠上皮细胞基底膜进入血淋巴,经由血淋巴的转运作用积累在脂肪体和表皮等组织中。6龄幼虫不同组织中所积累Ni2+的含量为中肠>脂肪体>表皮,且不同组织和粪便中的Ni2+都随饲料中Ni2+浓度的增加而增加,并存在显著的剂量-反应关系。研究结果可为进一步研究过量Ni2+对斜纹夜蛾幼虫的生长发育和繁殖的影响,以及斜纹夜蛾幼虫不同组织对Ni2+的解毒能力等提供一定依据。 相似文献
108.
109.
A. M. Rofe J. C. Philcox D. R. Haynes M. W. Whitehouse P. Coyle 《Biological trace element research》1992,34(3):237-248
The early changes in hepatic metallothionein (MT) and plasma zinc (Zn), copper (Cu), and iron (Fe) were investigated during
the induction of adjuvant (AJ) arthritis in rats in conjunction with cyclosporin (CSA) treatment. Plasma Zn decreased after
AJ injection (60% of control values at 8 h), and this was associated with a 4.5-fold increase in hepatic MT at 8 h. Plasma
Zn was lowest at 16 h (40% of control), whereas hepatic MT concentrations increased to a maximum of 20-fold at 16 h. Changes
in plasma Fe paralleled those of Zn, whereas plasma Cu levels were increased. Plasma metal and hepatic MT concentrations returned
toward normal from d 1–7. At d 14, when marked paw swelling was apparent, hepatic MT and plasma Cu were again increased and
plasma Zn decreased.
Administration of CsA decreased MT induction in rats injected with AJ and also caused a marked recovery in plasma Zn and Fe
levels. These changes were small but significant even in the early stages (up to 24 h) after AJ injection and were followed
by a sustained improvement in all parameters, corresponding to the nonappearance of clinical arthropathy in CsA-treated rats.
TNF-α and IL-6 production by peritoneal macrophages isolated from AJ-injected rats was significantly decreased by CsA treatment
at d 7 and 14. The inhibition of hepatic MT induction during acute and chronic inflammation by cyclosporin emphasizes the
role of the immune system in altered metal homeostasis in inflammation. 相似文献
110.
Fluorescent Pseudomonas species are characterized by the production of pyoverdin-type siderophores for Fe3+ acquisition in iron-limited environments. Since it produces a structurally specific pyoverdin, Pseudomonas putida strain BTP1 could represent a valuable tool in an attempt to correlate the structural features of these compounds with some specificity in their two main properties i.e. affinity for iron and recognition rate by other Pseudomonas strains. An uncommonly high affinity for iron of the pyoverdin synthetized by P. putida BTP1 was observed by comparing both the apparent stability constant and the decomplexation kinetic of its ferric complex with those of ferripyoverdins from other strains. On another hand, results from growth stimulation experiments and labeled ferripyoverdin uptake assays highlighted the very low recognition rate of BTP1 isopyoverdins by membrane receptors of foreign strains. By contrast, P. putida BTP1 was able to utilize a broad spectrum of structurally unrelated exogenous pyoverdins by means of multiple receptors that are likely constitutively expressed in its outer membrane. The unusual traits of its pyoverdin-mediated iron acquisition system should contribute to enlarge the ecological competence of Pseudomonas putida BTP1 in terms of colonization and persistence in the rhizosphere. 相似文献