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1.
Biol Trace Elem Res ; 165(2): 119-22, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25637566

RESUMO

Iliac artery aneurysms (IAA) and abdominal aortic aneurysms (AAA) frequently coexist. It remains unknown whether the content of trace elements in AAA walls depends on the coexistence of IAAs. The aim of this study was to compare the content of selected trace elements in AAA walls depending on the coexistence of IAAs. The content of trace elements was assessed in samples of AAA walls harvested intraoperatively in 19 consecutive patients. In the studied group, coexisting IAAs were diagnosed in 11 out of the 19 patients with AAA. The coexistence of IAAs was associated with a slightly lower content of nickel (0.28 (0.15-0.40) vs. 0.32 (0-0.85) mg/g; p = 0.09) and a significantly higher content of cadmium (0.71 (0.26-1.17) vs. 0.25 (0.20-0.31) mg/g; p = 0.04) in AAA walls. The levels of the remaining studied elements, copper, zinc, manganese, magnesium and calcium, were comparable. The elevated levels of cadmium in the walls of AAA coexisting with IAAs may suggest an impact of the accumulation of this trace element on the greater damage of the iliac artery wall.


Assuntos
Aneurisma da Aorta Abdominal/metabolismo , Aneurisma Ilíaco/metabolismo , Oligoelementos/análise , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/complicações , Cádmio/análise , Estenose das Carótidas/complicações , Feminino , Humanos , Hipertensão/complicações , Aneurisma Ilíaco/complicações , Artéria Ilíaca/patologia , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Níquel/análise , Fumar/efeitos adversos , Trombose/metabolismo
2.
J Trace Elem Med Biol ; 28(1): 28-31, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24220057

RESUMO

BACKGROUND: Intraluminal thrombus (ILT) formation plays a significant role in the progression of infrarenal abdominal aortic aneurysms (AAA). Potentially, as ILT thickness increases the availability of trace elements in the aneurysm wall could decrease thereby leading to oxidative stress and intensifying pro-inflammatory cytokine generation. AIM: To determine if thrombus thickness is related to the concentration of trace elements in the wall of infrarenal AAA. PATIENTS AND METHODS: The concentrations of trace elements in the wall of the aneurysm sack and ILT obtained from 19 consecutive patients during surgery for infrarenal AAA were determined using emission spectrometry. RESULTS: The concentrations of magnesium, zinc, manganese, and lead in the wall of AAA were significantly greater than in the ILT. Only the concentration of copper was lower in the AAA wall compared with the thrombus. The concentration of calcium, phosphorus, zinc, lead, copper, and magnesium increased with ILT thickness. The concentrations of no other trace elements in the wall of AAA were found to be related to the ILT thickness. CONCLUSIONS: Intraluminal thrombus thickness is not associated with a lower concentration of trace elements in the wall of the infrarenal AAA. Thus, the intraluminal thrombus participates in the progression of AAA by mechanisms independent of trace element supply to the wall of the aneurysm sack.


Assuntos
Aneurisma da Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/patologia , Trombose/complicações , Trombose/metabolismo , Oligoelementos/metabolismo , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
Ecotoxicology ; 22(9): 1422-34, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24085602

RESUMO

The purpose of this study was to determine the concentrations of heavy metals (cadmium, lead, zinc, copper, iron and manganese) in soil, their bioavailability and bioaccumulation in plants leaves. This study also examined their influences on the antioxidant response of the plants Cardaminopsis arenosa and Plantago lanceolata grown in metal-contaminated and non-contaminated soils. The activities of guaiacol peroxidase and superoxide dismutase and the levels of antioxidants such as glutathione, proline and non-protein thiols were measured. Concentrations of the examined metals were several to thousands of times lower in the potentially bioavailable fraction than in the acid-extracted fraction of the soil. Similar mode of antioxidant responses in plant leaves of metalliferous populations indicates the tolerance of plants towards heavy metals. However POD and GSHt had a particularly strong role in defense reactions, as their increase was the most common reaction to heavy metal contamination.The levels of Zn, Cd and Pb in the leaves of C. arenosa better reflected metal concentrations in the metalliferous and non-metalliferous soil than the determined metal concentrations in P. lanceolata. Bioaccumulated Zn, Cd and Pb concentrations were above or in the ranges mentioned as toxic for plant tissues and therefore the studied plants have potential for use in phytostabilization.


Assuntos
Antioxidantes/metabolismo , Arabidopsis/metabolismo , Metais Pesados/metabolismo , Plantago/metabolismo , Poluentes do Solo/metabolismo , Disponibilidade Biológica , Metais Pesados/farmacocinética
4.
C R Biol ; 335(4): 292-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22578575

RESUMO

The effect of Cd and Pb on endogenous and IAA-induced elongation growth and medium pH of maize coleoptile segments incubated at 20, 25 and 30 °C was studied. It was found that the elongation of coleoptile segments and proton extrusion increased with the temperature and reached its maximum at 30 °C. For Cd, the maximal inhibition of endogenous and IAA-induced growth as well as medium acidification of coleoptile segments was observed at 25 °C. Meanwhile, Pb, irrespective of the temperature, diminished the growth of the segments by ca. 20%, increasing the acidification of the incubation medium. It was also found that in contrast to Cd, Pb accumulation in maize coleoptile segments did not correlate with temperature. The results suggest that the toxic effect of Cd on elongation growth of coleoptile segments is connected with the decrease of the PM H(+)-ATPase activity and probably with Cd-induced high acivity of IAA oxidase, whereas the effect of Pb did not depend on activity of any of the enzymes.


Assuntos
Cádmio/toxicidade , Cotilédone/efeitos dos fármacos , Cotilédone/crescimento & desenvolvimento , Chumbo/toxicidade , Temperatura , Zea mays/efeitos dos fármacos , Zea mays/crescimento & desenvolvimento , Cádmio/metabolismo , Interpretação Estatística de Dados , Concentração de Íons de Hidrogênio , Chumbo/metabolismo , Zea mays/metabolismo
5.
Arch Environ Contam Toxicol ; 61(4): 568-77, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21424219

RESUMO

The effects of cadmium (Cd; 0.1-1000 µM) and fusicoccin (FC) on growth, Cd(2+) content, and membrane potential (E(m)) in maize coleoptile segments were studied. In addition, the E(m) changes and accumulation of Cd and calcium (Ca) in coleoptile segments treated with Cd(2+) combined with 1 µM FC or 30 mM tetraethylammonium (TEA) chloride (K(+)-channel blocker) were also determined. In this study, the effects of Ca(2+)-channel blockers [lanthanum (La) and verapamil (Ver)] on growth and content of Cd(2+) and Ca(2+) in coleoptile segments were also investigated. It was found that Cd at high concentrations (100 and 1000 µM) significantly inhibited endogenous growth of coleoptile segments and simultaneously measured proton extrusion. FC combined with Cd(2+) counteracted the toxic effect of Cd(2+) on endogenous growth and significantly decreased Cd(2+) content (not the case for Cd(2+) at the highest concentration) in coleoptile segments. Addition of Cd to the control medium caused depolarization of E (m), the extent of which was dependent on Cd concentration and time of treatment with Cd(2+). Hyperpolarization of E(m) induced by FC was suppressed in the presence of Cd(2+) at 1000 µM but not Cd(2+) at 100 µM. It was also found that treatment of maize coleoptile segments with 30 mM TEA chloride caused hyperpolarization of E (m) and decreased Cd(2+) content in coleoptile segments, suggesting that, in the same way as for FC, accumulation of Cd(2+) was dependent on plasma membrane (PM) hyperpolarization. Similar to FC, TEA chloride also decreased Ca(2+) content in coleoptile segments. La and Ver combined with Cd(2+) (100 µM) significantly decreased Cd content in maize coleoptile segments, but only La completely abolished the toxic effect of Cd(2+) on endogenous growth and growth in the presence of FC. Taken together, these results suggest that the mechanism by which FC counteracts the toxic effect of Cd(2+) (except at 1000 µM Cd(2+)) on the growth of maize coleoptile segments involves both stimulation of PM H(+)-ATPase activity by FC as well as Cd(2+)-permeable, voltage-dependent Ca channels, which are blocked by FC and TEA chloride-induced PM hyperpolarization.


Assuntos
Compostos de Cádmio/toxicidade , Cotilédone/efeitos dos fármacos , Glicosídeos/farmacologia , Micotoxinas/farmacologia , Zea mays/efeitos dos fármacos , Cotilédone/crescimento & desenvolvimento , Lantânio/farmacologia , Sementes/efeitos dos fármacos , Verapamil/farmacologia , Zea mays/crescimento & desenvolvimento
6.
Environ Geochem Health ; 33(6): 595-611, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21308401

RESUMO

Contents of mineral substance, silica, and a range of bioelements and toxic elements (Mg, Na, K, Ca, Ba, Zn, Cr, P Al, Cd, Mn Cu, Ni, Pb, Sr, Fe) in 38 livers of donors from the Upper Silesia Coal Basin (southern Poland) are presented. Elements were determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES) with the exception of silica that was estimated colorimetrically. Concentrations, concentration variability, and correlations between selected liver components determined for the total population are related to donor age, gender, and lesion occurrence. Correlations between particular elements were found using correlation coefficient values and the Fisher transformation. Mineral substance in the livers lies in the range 0.40-5.03 wt%. With increasing donor age, mineral-matter content decreases to a minimum for the 40-60 years of age range. Microbioelement contents show a similar tendency, while microbioelements and toxic elements reach maximum contents in donors aged 60-80 years. All elements show content decreases in livers from the oldest group (>80 years). Silica contents increase with age. Variability of element contents is lowest in the older subpopulations. Livers with lesions show lower element contents and variability. The results are compared to literature data for regions of Poland assumed to be of low pollution and to data from comparable regions in Japan and Hungary. Up to our knowledge, this paper is the first work describing the total contents, as distinct from contents of selected elements, of mineral substance in human livers.


Assuntos
Poluição Ambiental/análise , Fígado/química , Metais/análise , Minerais/análise , Oligoelementos/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Espectrofotometria Atômica
7.
Monatsh Chem ; 142(12): 1241-1247, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-26166855

RESUMO

ABSTRACT: Ru-catalyzed synthesis of mixed alkyl-alkyl acetals via addition of primary alcohols to allyl ethers has been extended to include long-chain and/or functionalized substrates. The catalytic systems for these reactions were generated from RuCl2(PPh3)3 and [RuCl2(1,5-COD)]x and phosphines [PPh3 or P(p-chlorophenyl)3] or SbPh3. Of particular importance is the almost quantitative elimination of transacetalization. The addition proceeds through allyl complexes, not via isomerization of allyl ethers--subsequent addition of ROH to vinyl ethers.

9.
Environ Pollut ; 150(3): 338-46, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17408823

RESUMO

The effects of chemophytostabilization practices on arbuscular mycorrhiza (AM) of Deschampsia cespitosa roots at different depths in soils highly contaminated with heavy metals were studied in field trials. Mycorrhizal parameters, including frequency of mycorrhization, intensity of root cortex colonization and arbuscule abundance were studied. Correlations between concentration of bioavailable Cd, Zn, Pb and Cu in soil and mycorrhizal parameters were estimated. An increase in AM colonization with increasing soil depth was observed in soils with spontaneously growing D. cespitosa. A positive effect of chemophytostabilization amendments (calcium phosphate, lignite) on AM colonization was found in the soil layers to which the amendments were applied. Negative correlation coefficients between mycorrhizal parameters and concentration of bioavailable Cd and Zn in soil were obtained. Our results demonstrated that chemophytostabilization practices enhance AM colonization in D. cespitosa roots, even in soils fertilized with high rates of phosphorus.


Assuntos
Recuperação e Remediação Ambiental/métodos , Metais Pesados/toxicidade , Micorrizas/fisiologia , Poaceae/crescimento & desenvolvimento , Poluentes do Solo/toxicidade , Biomassa , Cádmio/toxicidade , Fosfatos de Cálcio , Carvão Mineral , Cobre/toxicidade , Monitoramento Ambiental/métodos , Concentração de Íons de Hidrogênio , Chumbo/toxicidade , Poaceae/microbiologia , Microbiologia do Solo , Zinco/toxicidade
10.
Anal Bioanal Chem ; 385(5): 971-4, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16791580

RESUMO

Analysis of small samples of lanthanum-doped lead zirconate titanate (PLZT) by wavelength-dispersive X-ray fluorescence spectrometry (WDXRF) is presented. The powdered material in ca. 30 mg was suspended in water and collected on the membrane filter. The pure oxide standards (PbO, La2O3, ZrO2 and TiO2) were used for calibration. The matrix effects were corrected using a theoretical influence coefficients algorithm for intermediate-thickness specimens. The results from XRF method were compared with the results from the inductively coupled plasma optical emission spectrometry (ICP-OES). Agreement between XRF and ICP-OES analysis was satisfactory and indicates the usefulness of XRF method for stoichiometry determination of PLZT.

11.
Przegl Lek ; 63(10): 1011-4, 2006.
Artigo em Polonês | MEDLINE | ID: mdl-17288204

RESUMO

The problem of statistical characteristics of occurrence barium and strontium content in gallstones from smoking and non-smoking women living in southern Poland is presented in the work. The subjects of the research were gallstones, gained intraoperatively from 146 women (49 smoking, 97 non-smoking). The content of barium and strontium was determined using atomic emission spectroscopy with inductive coupled plasma (ICP-AES). The statistical characteristic of barium and strontium content in gallstones shows that smoking does not decide about content level of these elements in gallstones. Content of barium (2.32 microgBa/g) as well as strontium (3.23 microgSr/g) in gallstones from non smoking women are higher in comparison to content of these elements in gallstones from smoking women (1.91 microgBa/g and 2.76 microgSr/g).


Assuntos
Bário/análise , Cálculos Biliares/química , Cálculos Biliares/epidemiologia , Fumar/epidemiologia , Estrôncio/análise , Poluição por Fumaça de Tabaco/análise , Estudos de Casos e Controles , Comorbidade , Feminino , Humanos , Polônia/epidemiologia , Espectrofotometria Atômica
12.
Cell Mol Biol Lett ; 8(1): 97-103, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12655362

RESUMO

In this study, we examined the relationship between the accumulation of NaHSeO3, the plant hormone (IAA), and some nutrient elements (K(+), Na(+), Ca(2+)) in the tissues of the roots, mesocotyls and leaves of Zea mays L. plants. Our experiments were carried out with eight- to nine-day old maize plants (Zea mays L. var K33xF2) grown on Hoagland's medium containing the standard macro- and microelements, IAA and NaHSeO(3). The accumulation of selenium, potassium, sodium and calcium in the seedlings was measured by emission spectroscopy using a spectrometer with excitation by the argon inductively coupled plasma technique (ICP-AES). We observed that when selenite and phytohormone (IAA) are present in the external medium of growing plants, they change the uptake and accumulation of some cations (K(+), Na(+), Ca(2+)) in the leaf, mesocotyl and root tissues. The change of transport of some nutrient elements is probably one of the first observed symptoms of selenium's effects on plants.


Assuntos
Ácidos Indolacéticos/farmacologia , Metais/metabolismo , Selênio/toxicidade , Zea mays/efeitos dos fármacos , Zea mays/metabolismo , Cálcio/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Potássio/metabolismo , Selênio/metabolismo , Sódio/metabolismo , Selenito de Sódio/toxicidade , Zea mays/crescimento & desenvolvimento
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