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1.
J Mol Cell Cardiol ; 159: 16-27, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34139233

RESUMO

Chronic heart failure (HF) is often accompanied by systemic iron deficiency (ID). However, effects of ID on cardiac iron status and progression of HF are unknown. To investigate these effects rats underwent LAD ligation to induce post-myocardial infarction HF or sham operation. After 3 weeks the animals from both groups were randomized into three subgroups: control, moderate ID and severe ID+anemia (IDA) by a combination of phlebotomy and low iron diet for 5 weeks. Serum and hepatic iron content were reduced by 55% and 70% (ID) and by 80% and 77% (IDA), respectively, while cardiac iron content was unchanged in HF rats. Changes in expression of all cardiomyocyte iron handling proteins indicating preserved cardiomyocytes iron status in HF and ID/IDA. Contractile function of LV cardiomyocytes, Ca2+ transient amplitude, sarcoplasmic reticulum Ca2+ release and SERCA2a function was augmented by ID and IDA and it was accompanied by an increase in serum catecholamines. Neither ID nor IDA affected left ventricular (LV) systolic or diastolic function or dimensions. To sum up, systemic ID does not result in cardiac ID and does not affect progression of HF and even improves contractile function and Ca2+ handling of isolated LV cardiomyocytes, however, at the cost of increased catecholamine level. This suggests that intravenous iron therapy should be considered as an additional therapeutic option in HF, preventing the increase of catecholaminergic drive with its well-known long-term adverse effects.


Assuntos
Insuficiência Cardíaca/metabolismo , Ventrículos do Coração/metabolismo , Deficiências de Ferro/metabolismo , Ferro/metabolismo , Animais , Cálcio/metabolismo , Masculino , Contração Miocárdica/fisiologia , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Ratos , Ratos Wistar , Retículo Sarcoplasmático/metabolismo
2.
Chemosphere ; 237: 124442, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31369900

RESUMO

Present studies facilitated testing the hypothesis that sediment fraction <20 µm contains different amounts of REEs. The potentially bioavailable rare earth elements (REEs) were determined in the following fractions of the surface sediments of the Vistula River: <5 µm, 5-10 µm, 10-20 µm, and total <20 µm. The attempt was made to fractionate the sediment by self-adjustable split-flow transport-thin fractionation channel operating in the full depletion mode (SPLITT-FFD-SA), which is a new concept and so far unused method for such purposes. All three fractions were separated in the expected particle size ranges. The collected fractions were analyzed with the laser diffraction particle size analyzer and the inductively coupled plasma - mass spectrometer (ICP-MS) to determine the size and the elemental composition. ∑REEs in the Vistula sediments declined from 123.41, through 112.59 to 95.22 mg kg-1 in fractions: 10-20 µm, 5-10 µm, <5 µm, respectively. Eleven, out of sixteen REEs, showed statistically significant declining trend in REEs content, with decreasing particle sizes of sediment fractions. Particularly exceptional was Er, whose content in <5 µm fraction was by 12-20% higher than in larger size fractions. Rare earth elements of the Vistula sediments are considerably enriched in the light rare earth elements (LREEs) relative to the heavy rare earth elements (HREEs), with the LREEs/HREEs ratio declining from 4.01 (10-20 µm) to 3.599 (<5 µm). The sequence of mass weighted REEs content in <20 µm size fraction was as follows: Ce > La > Nd > Y > Sc > Pr > Sm > Gd > Dy > Er > Yb > Eu > Tb > Ho > Tm > Lu.


Assuntos
Sedimentos Geológicos/química , Metais Terras Raras/análise , Rios/química , Peso Molecular , Tamanho da Partícula
3.
Food Chem ; 292: 129-133, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31054656

RESUMO

Arsenic and its inorganic species: As (III), As (V), dimethylarsenic acid (DMA) and monomethylarsenic acid (MMA) were determined in hypoallergenic formulas and grain porridges commercially available on Polish market, dedicated for infant 0-8 months. After quantitative extraction with 0.5% HNO3, separation of individual species was performed by high performance liquid chromatography (HPLC), and their determination by neutron activation analysis (NAA) and inductively coupled plasma mass spectrometry (ICP-MS). Due to relatively low content of As in the analysed samples, it was only possible to determine DMA using the HPLC-ICP-MS mode. HPLC separation coupled with off-line determination by NAA enabled the determination of more extracted As species (especially inorganic) with good accuracy. Certified reference material (CRM) Rice Flour SRM 1568b (NIST) was used for the validation of both procedures.


Assuntos
Arsênio/análise , Cromatografia Líquida de Alta Pressão/métodos , Alimentos Infantis/análise , Espectrometria de Massas/métodos , Análise de Ativação de Nêutrons/métodos , Arsenicais/análise , Ácido Cacodílico/análise , Humanos , Lactente
4.
Sci Rep ; 8(1): 15758, 2018 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-30361476

RESUMO

Iron deficiency (ID) commonly occurs in chronic heart failure (HF) and is associated with poor prognosis. Neither its causes nor pathophysiological significance are clearly understood. We aimed to assess iron status and the effect of iron supplementation in the rat model of post-myocardial infarction (MI) HF. Four weeks after induction of MI to induce HF or sham surgery, rats received intravenous iron (ferric carboxymaltose) or saline, 4 doses in 1-week intervals. HF alone did not cause anemia, systemic or myocardial ID, but reduced myocardial ferritin, suggesting depleted cardiomyocyte iron stores. Iron therapy increased serum Fe, ferritin and transferrin saturation as well as cardiac and hepatic iron content in HF rats, but did not increase myocardial ferritin. This was accompanied by: (1) better preservation of left ventricular (LV) ejection fraction and smaller LV dilation, (2) preservation of function of Ca2+ handling proteins in LV cardiomyocytes and (3) reduced level of inflammatory marker, CRP. Furthermore, iron supplementation did not potentiate oxidative stress or have toxic effects on cardiomyocyte function, but increased activity of antioxidant defenses (cardiac superoxide dismutase). Despite lack of systemic or myocardial ID we found evidence of depleted cardiomyocyte iron stores in the rat model of HF. Furthermore we observed positive effect of iron supplementation and confirmed safety of iron supplementation in this setting.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Espaço Intracelular/metabolismo , Ferro/administração & dosagem , Ferro/uso terapêutico , Miocárdio/metabolismo , Animais , Biomarcadores/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Modelos Animais de Doenças , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Inflamação/sangue , Injeções Intravenosas , Ferro/sangue , Ferro/farmacologia , Fígado/metabolismo , Masculino , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar
5.
Biol Trace Elem Res ; 186(2): 589-596, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29679351

RESUMO

The aim of this study was to assess the levels of 13 essential and toxic elements (As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Se, V, Zn) in the infant formulas, available on Polish market. Selected food samples were of animal (cow- and goat-based milks) and plant (soy-based milk, hypoallergic products, grain porridges) origin. Two analytical techniques, inductively coupled plasma mass spectrometry (ICP-MS) and neutron activation analysis (NAA), have been complementarily applied to analyze elemental content of 16 formulas dedicated for infants between 0 and 8 months. For arsenic determinations, the radiochemical mode of NAA was also used. The daily intake of some micronutrients in the age 0-8 months for non-breastfed infants was estimated and compared with present safety limits. Certified reference materials (CRMs) have been used for the validation of the methods: Non-fat Milk Powder 1549 (National Bureau of Standards-NBS), Soya Bean Flour INCT-SBF-4 (Institute of Nuclear Chemistry and Technology-INCT), Rice Flour SRM 1568b (National Institute of Standards and Technology-NIST).


Assuntos
Glycine max/química , Fórmulas Infantis/química , Leite/química , Oligoelementos/análise , Animais , Bovinos , Feminino , Cabras , Humanos , Lactente , Recém-Nascido , Espectrometria de Massas , Análise de Ativação de Nêutrons , Polônia , Pós/química
6.
J Radioanal Nucl Chem ; 311(2): 1347-1353, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28250548

RESUMO

In this work a determination of selected elements in the infant formulas commercially available on the Polish market was done. 14 different materials (milk-based formulas and grain porridges) were analyzed. Both, inductively coupled plasma mass spectrometry (ICP-MS) and instrumental neutron activation analysis (INAA) were applied for the determination of As, Cr, Fe and Se, which are recognized as the problematic elements for ICP-MS. For As and Se, the radiochemical NAA was also used. The daily intake of Se and Fe in the age 0-6 months for non-breast fed infants was estimated and compared with present safety limits.

7.
Chemosphere ; 169: 181-187, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27883912

RESUMO

Regular use of a reference material and participation in a proficiency testing program can improve the reliability of analytical data. This paper presents the preparation of candidate reference materials for the drugs metoprolol, propranolol, carbamazepine, naproxen, and acenocoumarol in freshwater bottom sediment and cod and herring tissues. These reference materials are not available commercially. Drugs (between 7 ng/g and 32 ng/g) were added to the samples, and the spiked samples were freeze-dried, pulverized, sieved, homogenized, bottled, and sterilized by γ-irradiation to prepare the candidate materials. Procedures for extraction and liquid chromatography coupled with tandem mass spectrometry were developed to determine the drugs of interest in the studied material. Each target drug was quantified using two analytical procedures, and the results obtained from these two procedures were in good agreement with each other. Stability and homogeneity assessments were performed, and the relative uncertainties due to instability (for an expiration date of 12 months) and inhomogeneity were 10-25% and 4.0-6.8%, respectively. These procedures will be useful in the future production of reference materials.


Assuntos
Monitoramento Ambiental/métodos , Peixes/metabolismo , Poluentes Químicos da Água/análise , Acenocumarol/análise , Acenocumarol/metabolismo , Animais , Carbamazepina/análise , Carbamazepina/metabolismo , Cromatografia Líquida/métodos , Monitoramento Ambiental/normas , Metoprolol/análise , Metoprolol/metabolismo , Naproxeno/análise , Naproxeno/metabolismo , Propranolol/análise , Propranolol/metabolismo , Padrões de Referência , Reprodutibilidade dos Testes , Alimentos Marinhos , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/normas
8.
J Radioanal Nucl Chem ; 310(2): 559-564, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27746516

RESUMO

A procedure based on radiochemical neutron activation analysis was developed for the determination of chromium in biological materials. The procedure consists of irradiation of reference and test samples in a nuclear reactor, microwave sample digestion, selective and quantitative radiochemical separations of chromium and gamma-ray spectrometric measurement of 51Cr. Separation of chromium from the accompanying elements was done on the column packed with inorganic resin MnO2 Resin. Distribution coefficients of Cr, Zn, Co, Cs and Sc were determined in the system: MnO2 Resin-HCl, HNO3 and H2SO4. Accuracy of the procedure was checked by analysis of certified reference materials.

10.
Food Chem ; 142: 178-87, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24001829

RESUMO

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for selenium speciation in dietary supplements. Chromatographic separation was performed on a TSK-Gel ODS-100V column using a mixture of 5mM ammonium acetate water solution and methanol as a mobile phase. Conditions chosen for this process allowed to separate all investigated chemical compounds of selenium: seleno-l-methionine, methyl-seleno-l-cysteine, l-selenocystine, methaneseleninic acid, selenite and selenate. A tandem mass spectrometer with an ion trap operating in negative or positive ion mode according to the selenium form being determined was used as a detector. Three extraction procedures: water extraction, enzymatic hydrolysis and sequential extraction were used for preparation of samples for the determination of the actual forms of selenium in diet supplements. The developed method was used for analysis of six dietary supplements containing selenium bought in a pharmacy and supermarket. Apart from speciation analysis of selenium content in supplements total selenium content was determined using instrumental neutron activation analysis (INAA). All expected forms of selenium except for selenite were determined using LC-MS/MS technique. It should be stressed that amounts of selenate were smaller than expected.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Compostos Organosselênicos/química , Selênio/química , Espectrometria de Massas em Tandem/métodos , Estrutura Molecular
11.
Anal Chim Acta ; 806: 97-100, 2014 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-24331044

RESUMO

Hafnium at the very low level of 1-8 ppm (in relation to zirconium) was determined in zirconium sulfate solutions (originating from investigations of the separation of ca. 44 ppm Hf from zirconium by means of the ion exchange method) by using three independent methods: inductively coupled plasma mass spectrometry (ICP MS), neutron activation analysis (NAA) and inductively coupled plasma atomic emission spectrometry (ICP-AES). The results of NAA and ICP MS determinations were consistent with each other across the entire investigated range (the RSD of both methods did not exceed 38%). The results of ICP-AES determination were more diverse, particularly at less than 5 ppm Hf (RSD was significantly higher: 29-253%). The ion exchange method exploiting Diphonix(®) resin proved sufficient efficiency in Zr-Hf separation when the initial concentration ratio of the elements ([Zr]0/[Hf]0) ranged from 1200 to ca. 143,000.

12.
Appl Radiat Isot ; 75: 115-27, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23501361

RESUMO

The gel composites of WO3-ZrO2, WO3-TiO2, WO3-ZrO2-SiO2 at different molar ratios of oxides were synthesized. The elution profiles of the generator columns packed with gel samples activated at the Polish nuclear research reactor MARIA were studied. The best results of elution were found for WO3-ZrO2 and WO3-TiO2 both at 1:2M ratio annealed at 500°C and 650°C, respectively. Their structure determined with X-ray and neutron diffraction is completely amorphous with spherical grains of ∼23nm diameter. The efficiency of (188)W/(188)Re generators with WO3-ZrO2 gel of natural isotope composition as well as enriched in (186)W were investigated.


Assuntos
Óxidos/química , Radioisótopos/química , Compostos Radiofarmacêuticos/síntese química , Rênio/química , Tungstênio/química , Géis , Óxidos/síntese química , Dióxido de Silício/química , Titânio/química , Zircônio/química
13.
ScientificWorldJournal ; 2012: 216380, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22536124

RESUMO

The preparation, certification, and characterization of two new biological certified reference materials for inorganic trace analysis have been presented. They are based on two different varieties of tobacco leaves, namely, Oriental Basma Tobacco Leaves (INCT-OBTL-5), grown in Greece, and Polish Virginia Tobacco Leaves (INCT-PVTL-6), grown in Poland. Certification of the materials was based on the statistical evaluation of results obtained in a worldwide interlaboratory comparison, in which 87 laboratories from 18 countries participated, providing 2568 laboratory averages on nearly 80 elements. It was possible to establish the certified values of concentration for many elements in the new materials, that is, 37 in INCT-OBTL-5 and 36 in INCT-PVTL-6, including several toxic ones like As, Cd, Hg, Pb, and so forth. The share and the role of instrumental analytical techniques used in the process of certification of the new CRMs are discussed.


Assuntos
Nicotiana/química , Folhas de Planta/química , Oligoelementos/análise , Laboratórios , Tamanho da Partícula , Folhas de Planta/toxicidade , Padrões de Referência
14.
Appl Radiat Isot ; 70(5): 819-22, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22342310

RESUMO

A new radiochemical separation scheme based on extraction chromatography has been proposed for isolation of arsenic from selenium. The distribution coefficients of As and Se on prepared sorbents: (selected aromatic o-diamines supported on polystyrene adsorbents) were determined in order to find the best condition for separation of both the elements. Batch experiments were verified by column studies. This work, together with earlier results from this Laboratory, enabled to elaborate a new separation scheme for selective and quantitative separation of arsenic from selenium. Proposed approach insures high selectivity and radionuclide purity of separated arsenic fraction; it is also characterized by high elution efficiency (>95%) using small volume (2 mL) of 0.9% NaCl with very low breakthrough (<0.01%) of selenium.

15.
Int J Cardiol ; 159(1): 47-52, 2012 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-21899903

RESUMO

BACKGROUND: Although, correction of iron deficiency and/or anemia in heart failure (HF) with iron seems promising, little is known about myocardial iron load and homeostasis. Moreover iron supplementation indications are solely based on iron serum markers. The purpose was to assess myocardial iron (M-Iron), ferritin (M-FR), transferrin receptor (M-sTfR) in HF in relation to serum Iron markers. METHODS AND RESULTS: Study group 33 patients, left/right ventricle (LV/RV) (LVEDV 245 ± 84 ml; LVESV 189 ± 85 ml; LVEF 22 ± 11%; RVD 32 ± 10 mm), NTproBNP (5464 ± 4825 pg/ml). Iron homeostasis assessment serum: iron, FR, transferrin/saturation (TSAT), sTfR; myocardial: M-Iron (Instrumental Neutron Activation Analysis, µg/g), M-FR, M-sTfR (ELISA - ng/mg protein) in the explanted failing hearts (FH), compared to non-failing hearts (NFH n=11). In FH as compared to NFH, M-Iron was reduced in RV (174 ± 45 vs 233 ± 97, respectively, p=0.07), LV (189 ± 58 vs 265 ± 119, p=0.04), without significant changes in M-FR/M-sTfR. Out of all serum iron markers only sTfR was negatively correlated with M-Iron in either ventricle (RV r=-0.44, p=0.03, LV r=-0.38, p=0.07). With regard to serum iron status, based on TSAT, patients were divided into two subgroups: reduced (TSAT<15%; n=11) and not-reduced serum iron (TSAT ≥ 15%; n=22). Both subgroups had similar grade of LV/RV dysfunction, NT-proBNP levels. M-FR was lower in TSAT<15% than in TSAT ≥ 15% (LV -31 ± 26 vs 46 ± 29; p=0.07) and (RV -24 ± 24 vs 43 ± 29; p=0.02), without differences in M-Iron and M-sTfR. CONCLUSIONS: In HF, M-Iron levels were reduced. Serum iron markers did not reflect M-Iron levels, except for serum sTfR. In reduced serum iron group, decrease in myocardial storage protein M-FR was observed.


Assuntos
Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/metabolismo , Homeostase/fisiologia , Ferro/metabolismo , Miocárdio/metabolismo , Índice de Gravidade de Doença , Adulto , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Talanta ; 71(2): 529-36, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19071337

RESUMO

The idea of highly accurate (definitive) methods by radiochemical neutron activation analysis (RNAA) is presented and illustrated with several examples of methods worked out in this Laboratory over the past several years. Definitive methods by RNAA are constructed by combining reactor neutron activation with very selective and quantitative post-irradiation separation of the indicator radionuclide by column chromatography followed by gamma-ray spectrometric measurement. All conditions for the determination of the individual element are optimized and uncertainties associated with every step of the analytical procedure are minimized. Even after the method has been thoroughly elaborated and validated through the analysis of appropriate certified reference materials (CRMs), the results obtained in each series of measurements are acknowledged as obtained by definitive method only when a series of previously formulated criteria is simultaneously fulfilled. The examples of definitive methods for the determination of cadmium, cobalt and molybdenum, respectively, in biological materials are presented. Each of these methods has detection limit of the order of ng g(-1) or better, and yields accurate and precise results. The expanded standard uncertainty is of the order of 2.6% for the case of single-element determination (Co) and 3.4-5.2% for the less favourable case (Mo) where there is necessity for simultaneous determination of uranium to correct for interference due to fission reaction. Definitive methods by RNAA may constitute an option or alternative with respect to ID-MS as methods of "guaranteed accuracy" being also a perspective solution in the case of monoisotopic elements, for which ID-MS cannot be used.

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