Metal accumulation
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The accumulation of heavy metals in plants is a function of uptake capacity and intracellular binding sites. The concentrations of heavy metals in plants growing in constructed wetlands vary considerably between species and systems but in general, the concentrations are within the range commonly found in natural stands. The highest concentrations are mostly found in roots, followed by rhizomes, leaves and stems. Unfortunately, concentration values are commonly used to evaluate the 'accumulation' of heavy metals, but this approach is not correct. In order to evaluate heavy metal accumulation, the biomass of particular plant parts must be taken into consideration. In addition, there are two other factors, which need to be taken into consideration when accumulation is evaluated, namely seasonality and distribution within the plant shoot. It has been found that the seasonal distribution of heavy metals in the biomass varies between heavy metals and mostly does not follow the pattern known for nutrients. In addition, the concentration and accumulation of heavy metals vary considerably within the shoot and this fact should be taken into consideration when analyses are carried out.
Některá neurologická onemocnění způsobená akumulací kovů v CNS jsou léčitelná. Pro všechna tato onemocnění platí, že neurologické příznaky jsou reverzibilní, pouze pokud se léčba zahájí včas. Nejlepších výsledků je dosaženo, pokud se léčba zahájí ještě před vznikem neurologických příznaků. V této kapitole jsou probrány klinické projevy, diagnostika a léčebné strategie u léčitelných onemocnění s akumulací mědi (Wilsonova nemoc), kalcia (hypoparathyreóza), manganu (poruchy transportérů SLC30A10 a SLC39A14) a železa (aceruloplasminemie).
Some neurological diseases caused by accumulation of iron in CNS are treatable. If the initiation of treatment is early, neurological symptoms may be reversibile. The best results are achieved when the treatment is started before the manifestation of neurological symptoms. In this chapter we summarize the clinical features, diagnosis and treatment strategies in treatable diseases with the accumulation of copper (Wilson's disease), calcium (hypoparathyroidism), manganese (SLC30A10 and SLC39A14 transporter deficiency) and iron (aceruloplasminaemia).
Indirect impact of humic acid (HA) on metal accumulation and toxicity (Cd, Ni, Pb, and Hg; 100 μM; 24 h of exposure) in Scenedesmus quadricauda was studied. Algae were pre-cultured on solid (10 and 100 mg HA/L) or in liquid media (1, 5, and 10 mg HA/L) over 30 days and then exposed to metals mentioned above. Accumulation of applied metals irrespective of pre-culture increased in the order Ni < Cd < Pb < Hg. Algae pre-cultured on solid HA-enriched media accumulated more Cd (+ 46% at 10 mg HA/L), Ni (+ 50 and + 81% at 10 and 100 mg HA/L, respectively), and Pb (+ 15% at 100 mg HA/L) but the impact on Hg amount was not detected. Potassium and calcium decreased in response to all metals (K strongly under Hg excess) and HA had negligible impact. Interestingly, fluorescence microscopy detection of reactive oxygen species/nitric oxide (ROS/NO) balance showed that HA pre-culture suppressed ROS signal and stimulated NO signal in response to Cd (indicating positive impact of HA) while ROS signal in Ni and Pb treatments rather increased but NO signal decreased as expected from elevated Ni and Pb accumulation. Hg had clearly the most toxic impact on the ROS/NO balance. Algae pre-cultured in liquid HA-enriched media showed significantly increased Ni accumulation only (+ 14% at a dose 10 mg HA/L). Present study for the first time showed that humic acid may indirectly affect accumulation of metals and that solid HA-enriched medium used for pre-culture is more suitable to increase accumulation of metals by algae.
- MeSH
- chemické látky znečišťující vodu toxicita MeSH
- fluorescenční mikroskopie MeSH
- huminové látky analýza MeSH
- mikrořasy účinky léků MeSH
- oxidační stres MeSH
- reaktivní formy kyslíku metabolismus MeSH
- Scenedesmus účinky léků MeSH
- testy akutní toxicity MeSH
- těžké kovy toxicita MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- Publikační typ
- časopisecké články MeSH
Blood purification, ISSN 0253-5068 vol. 23, suppl. 1, 2005
23 s. : il., tab. ; 28 cm
- MeSH
- chronická nemoc MeSH
- dialýza ledvin MeSH
- kardiovaskulární nemoci MeSH
- kovy krev MeSH
- minerály krev MeSH
- nemoci ledvin patofyziologie MeSH
- Publikační typ
- sborníky MeSH
- Konspekt
- Patologie. Klinická medicína
- NLK Obory
- hematologie a transfuzní lékařství
- nefrologie
The brain has a unique biological complexity and is responsible for important functions in the human body, such as the command of cognitive and motor functions. Disruptive disorders that affect this organ, e.g. neurodegenerative diseases (NDDs), can lead to permanent damage, impairing the patients' quality of life and even causing death. In spite of their clinical diversity, these NDDs share common characteristics, such as the accumulation of specific proteins in the cells, the compromise of the metal ion homeostasis in the brain, among others. Despite considerable advances in understanding the mechanisms of these diseases and advances in the development of treatments, these disorders remain uncured. Considering the diversity of mechanisms that act in NDDs, a wide range of compounds have been developed to act by different means. Thus, promising compounds with contrasting properties, such as chelating agents and metal-based drugs have been proposed to act on different molecular targets as well as to contribute to the same goal, which is the treatment of NDDs. This review seeks to discuss the different roles and recent developments of metal-based drugs, such as metal complexes and metal chelating agents as a proposal for the treatment of NDDs.
- MeSH
- amyloid chemie metabolismus MeSH
- amyloidní beta-protein chemie metabolismus MeSH
- chelátory chemie farmakologie terapeutické užití MeSH
- kovy chemie metabolismus MeSH
- lidé MeSH
- neurodegenerativní nemoci farmakoterapie etiologie metabolismus patologie MeSH
- přehodnocení terapeutických indikací léčivého přípravku MeSH
- simulace molekulární dynamiky MeSH
- simulace molekulového dockingu MeSH
- vyvíjení léků * MeSH
- vztahy mezi strukturou a aktivitou MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Trace elements, such as iron, copper, manganese, and calcium, which are essential constituents necessary for cellular homeostasis, become toxic when present in excess quantities. In this article, we describe disorders arising from endogenous dysregulation of metal homeostasis leading to their tissue accumulation. Although subgroups of these diseases lead to regional brain metal accumulation, mostly in globus pallidus, which is susceptible to accumulate divalent metal ions, other subgroups cause systemic metal accumulation affecting the whole brain, liver, and other parenchymal organs. The latter group comprises Wilson disease, manganese transporter deficiency, and aceruloplasminemia and responds favorably to chelation treatment.
- MeSH
- chelátová terapie MeSH
- duševní poruchy etiologie MeSH
- hepatolentikulární degenerace epidemiologie etiologie patofyziologie terapie MeSH
- kovy metabolismus toxicita MeSH
- lidé MeSH
- mozek metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- audiovizuální média MeSH
- časopisecké články MeSH
- přehledy MeSH
