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1.
Scand J Clin Lab Invest ; 73(3): 253-61, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23448533

RESUMO

Reference intervals are crucial decision-making tools aiding clinicians in differentiating between healthy and diseased populations. However, for children such values often are lacking or incomplete. Blood samples were obtained from 689 healthy children, aged 6 months to 18 years, recruited in day care centers and schools. Hematology and anemia analytes were measured on the Siemens Advia 2120 and Abbott Architect ci8200 platforms (hemoglobin, erythrocyte volume fraction [EVF], erythrocytes, mean corpuscular volume [MCV], mean corpuscular hemoglobin [MCH], mean corpuscular hemoglobin concentration [MCHC], reticulocytes, leukocytes, lymphocytes, monocytes, neutrophils, eosinophils, basophils, platelets, iron, transferrin, transferrin saturation). Age- and gender-specific pediatric reference intervals were defined by calculating 2.5th and 97.5th percentiles. The data generated is primarily applicable to a Caucasian population, but could be used by any laboratory if verified for the local patient population.


Assuntos
Índices de Eritrócitos/fisiologia , Ferro/sangue , Transferrina/análise , Adolescente , Biomarcadores/sangue , Contagem de Células Sanguíneas/normas , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Ferro/normas , Masculino , Valores de Referência , Transferrina/normas , População Branca
2.
Artigo em Inglês | MEDLINE | ID: mdl-21879849

RESUMO

Arsenic (As) enrichment in groundwater has become a major global environmental disaster. Groundwater samples were collected from 64 sites located in the districts of 24-Parganas (S), and Nadia in West Bengal, India (Bhagirathi sub-basin), and 51 sites located in the districts of Comilla, Noakhali, Magura, Brahman baria, Laxmipur, Munshiganj, Faridpur and Jhenaida in Bangladesh (Padma-Meghna sub-basin). Groundwater samples were also collected from two As-affected areas (Chianan and Lanyang plains) of Taiwan (n = 26). The concentrations of major solutes in groundwater of the Padma-Meghna sub-basin are more variable than the Bhagirathi sub-basin, suggesting variations in the depositional and hydrological settings. Arsenic concentrations in groundwaters of the studied areas showed large variations, with mean As concentrations of 125 µg/L (range: 0.20 to 1,301 µg/L) in Bhagirathi sub-basin, 145 µg/L (range: 0.20 to 891 µg/L) in Padma-Meghna sub-basin, 209 µg/L (range: 1.3 to 575 µg/L) in Chianan plain, and 102 µg/L (range: 2.5 to 348 µg/L) in Lanyang plain groundwater. The concentrations of Fe, and Mn are also highly variable, and are mostly above the WHO-recommended guideline values and local (Indian and Bangladeshi) drinking water standard. Piper plot shows that groundwaters of both Bhagirathi and Padma-Meghna sub-basins are of Ca-HCO(3) type. The Chianan plain groundwaters are of Na-Cl type, suggesting seawater intrusion, whereas Lanyang plain groundwaters are mostly of Na-HCO(3) type. The study shows that reductive dissolution of Fe(III)-oxyhydroxides is the dominant geochemical process releasing As from sediment to groundwater in all studied areas.


Assuntos
Arsênio/análise , Água Potável/química , Água Subterrânea/química , Poluentes Químicos da Água/análise , Adsorção , Arsênio/química , Bangladesh , Água Potável/análise , Água Potável/normas , Monitoramento Ambiental/métodos , Compostos Férricos/análise , Compostos Férricos/química , Água Subterrânea/análise , Índia , Ferro/análise , Ferro/química , Ferro/normas , Manganês/análise , Manganês/química , Manganês/normas , Compostos de Manganês/análise , Compostos de Manganês/química , Oxirredução , Taiwan , Poluentes Químicos da Água/química
3.
Magnes Res ; 20(1): 43-52, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17536488

RESUMO

The aim of the present study was to define referential values of 5 basic bioelements (Ca, Mg, Zn, Cu, Fe) and 2 toxic metals (Pb and Cd) in the hair of Polish adults aged 20 to 40 years, based on the research conducted from 1991 to 2006 on a group of 5733 formally healthy subjects of both sexes. The results of our biochemical tests were subjected to statistical analysis and they can be treated as referential norms for the concentrations of analyzed bioelements in the hair of the Polish population. Our analyses confirm significant differences in accumulations of certain elements in women's and men's hair. We established that women's hair Ca, Mg, Zn (p = 0.000000) and hair Cu (p = 0.0001) concentrations are higher than they are in men. A lower mean of hair Fe concentrations in women were confirmed by some tests. Men have significantly higher (p = 0.0000) concentrations of toxic metals (hair Pb and Cd), which keep increasing with age. Analyses of correlations confirm significance (for the assumed level of significance alpha = 0.05) of synergistic interactions between bioelements: Ca-Mg (r = +0.70), Ca-Zn (r = +0.39), Ca-Cu (r = +0.14), Mg-Zn (r = +0.31), Mg-Cu (r = +0.10), Zn-Cu (r = +0.11), Zn-Fe (r = +0.07). Significance (a < 0.05) of antagonistic interactions with toxic metals: Ca-Pb (r = -0.13), Zn-Pb (r = -0.15), Mg-Pb (r = -0.15), Zn-Cd (r =-0.02) was confirmed. Significance (alpha < 0.05) of synergistic effects with toxic metals: Pb-Cd (r = +0.35), Fe-Pb (r = +0.16), Fe-Cd (r = +0.08) was also confirmed. Adults in whose hair bioelements and hair toxic metals concentrations have shown values outlying from reference and who have too many toxic elements and too few bioelements should undergo further diagnostic tests since the results could be a sign of disturbances that could lead to various diseases.


Assuntos
Exposição Ambiental/análise , Cabelo/química , Metais Pesados/análise , Metais/análise , População Branca , Adulto , Fatores Etários , Análise de Variância , Cádmio/análise , Cálcio/análise , Cobre/análise , Feminino , Humanos , Ferro/análise , Ferro/normas , Chumbo/análise , Magnésio/análise , Masculino , Polônia , Padrões de Referência , Fatores Sexuais , Zinco/análise
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(9): 1732-4, 2006 Sep.
Artigo em Zh | MEDLINE | ID: mdl-17112057

RESUMO

Using yttrium phosphate as the coprecipitation collector for the separation and preconcentration of trace lead and iron in nickel chloride and manganese sulfate, flame atomic absorption spectrometric (FAAS) determination was described in the present paper. Coprecipitation parameters including the pH of the solution, and the amounts of YCl3 and H3 PO4 were discussed. It was found that lead and iron in nickel chloride could be coprecipitated quantitatively in the range of pH 3.0-4.0, and so could be lead in manganese sulfate. The detection limits (3sigma) of lead and iron in 20 mL solution were 1.63 x 10(-2) mg x L(-1) and 4.58 x 10(-2) mg x L(-1) respectively. In NiCl2 solution the standard addition recoveries for lead and iron were 100.91% and 99.73% respectively, and in MnSO4 solution the standard addition recoveries were 99.45% and 98.98% respectively. The method has eliminated the interference of matrix, and the result is satisfied.


Assuntos
Ferro/análise , Chumbo/análise , Compostos de Manganês/química , Níquel/química , Espectrofotometria Atômica/métodos , Sulfatos/química , Ítrio/química , Precipitação Química , Concentração de Íons de Hidrogênio , Ferro/isolamento & purificação , Ferro/normas , Chumbo/isolamento & purificação , Chumbo/normas , Fosfatos/química , Padrões de Referência , Reprodutibilidade dos Testes
5.
Ann Lab Med ; 36(5): 481-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27374715

RESUMO

BACKGROUND: Reference intervals need to be established according to age. We established reference intervals of hematology and chemistry from community-based healthy 1-yr-old children and analyzed their iron status according to the feeding methods during the first six months after birth. METHODS: A total of 887 children who received a medical check-up between 2010 and 2014 at Boramae Hospital (Seoul, Korea) were enrolled. A total of 534 children (247 boys and 287 girls) were enrolled as reference individuals after the exclusion of data obtained from children with suspected iron deficiency. Hematology and clinical chemistry analytes were measured, and the reference value of each analyte was estimated by using parametric (mean±2 SD) or nonparametric methods (2.5-97.5th percentile). Iron, total iron-binding capacity, and ferritin were measured, and transferrin saturation was calculated. RESULTS: As there were no differences in the mean values between boys and girls, we established the reference intervals for 1-yr-old children regardless of sex. The analysis of serum iron status according to feeding methods during the first six months revealed higher iron, ferritin, and transferrin saturation levels in children exclusively or mainly fed formula than in children exclusively or mainly fed breast milk. CONCLUSIONS: We established reference intervals of hematology and clinical chemistry analytes from community-based healthy children at one year of age. These reference intervals will be useful for interpreting results of medical check-ups at one year of age.


Assuntos
Testes de Química Clínica/normas , Testes Hematológicos/normas , Ferro/sangue , Aleitamento Materno , Feminino , Humanos , Lactente , Ferro/normas , Masculino , Valores de Referência , República da Coreia
6.
Nutrients ; 8(1)2016 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-26784227

RESUMO

Fortified rice holds great potential for bringing essential micronutrients to a large part of the world population. The present study quantified the losses of three different micronutrients (vitamin A, iron, zinc) in fortified rice that were produced using three different techniques (hot extrusion, cold extrusion, and coating) and stored at two different environments (25 ± 5 °C at a humidity of 60% and 40 ± 5 °C at a humidity of 75%) for up to one year. Fortified rice premix from the different techniques was mixed with normal rice in a 1:100 ratio. Each sample was analyzed in triplicate. The study confirmed the high stability of iron and zinc during storage while the retention of vitamin A was significantly affected by storage and the type of techniques used to make rice premix. Losses for iron and zinc were typically <10% for any type of rice premix. After 12 months at mild conditions (25 °C and humidity of 60%), losses for vitamin A ranged from 20% for cold extrusion, 30% for hot extruded rice 77% for coated rice premix. At higher temperatures and humidity, losses of vitamin A were 40%-50% for extruded premix and 93% for coated premix after 6 months. We conclude that storage does lead to a major loss of vitamin A and question whether rice is a suitable food vehicle to fortify with vitamin A. For Cambodia, fortification of rice with iron and zinc could be an effective strategy to improve the micronutrient status of the population if no other food vehicles are available.


Assuntos
Armazenamento de Alimentos/métodos , Alimentos Fortificados/análise , Ferro/análise , Oryza/química , Vitamina A/análise , Zinco/análise , Camboja , Armazenamento de Alimentos/normas , Alimentos Fortificados/normas , Umidade/efeitos adversos , Ferro/normas , Micronutrientes/análise , Micronutrientes/normas , Programas Nacionais de Saúde/normas , Temperatura , Oligoelementos/análise , Oligoelementos/normas , Vitamina A/normas , Zinco/normas
7.
Int J Pharm ; 196(2): 169-72, 2000 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-10699711

RESUMO

High pressure homogenisation is a method for the production of nanosuspensions. In this process crystalline drug particles are pressed with high pressure through a narrow homogenisation gap. Due to the conditions in the gap it seems possible that metal erosion can occur. In this study the heavy metal (Fe) contamination of nanosuspensions produced by high pressure homogenisation was determined. Therefore nanosuspensions were analysed by atom absorption spectroscopy concerning their load of iron which is chosen as reference metal. The results show that the erosion of metal is below 1 ppm and will not cause any toxicological problems.


Assuntos
Contaminação de Medicamentos/prevenção & controle , Metais Pesados/análise , Suspensões/química , Calibragem , Química Farmacêutica/instrumentação , Química Farmacêutica/métodos , Ferro/análise , Ferro/normas , Metais Pesados/normas , Espectrofotometria Atômica , Suspensões/normas
8.
Eur J Obstet Gynecol Reprod Biol ; 61(1): 65-71, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8549850

RESUMO

There is world-wide concern that women of childbearing age cannot meet the increased iron needs during pregnancy. In the industrial world however, iron supplementation during pregnancy is a controversial issue. On the one hand, selective iron supplementation after iron status assessment has been recommended because not all women need iron, and compliance is likely to be better when an individual's need is recognized. On the other hand, routine iron supplementation to all women in the second half of pregnancy has been advocated in order to reach all women without the difficulties associated with assessment of iron status. Pregnant women could possibly meet their iron needs by increasing iron absorption efficiency. Although in that case, dietary counselling may prevent anaemia during pregnancy, supplementation with iron will be necessary to cure iron-deficiency anaemia.


Assuntos
Ferro/normas , Gravidez/fisiologia , Adulto , Anemia Ferropriva/sangue , Anemia Ferropriva/epidemiologia , Anemia Ferropriva/prevenção & controle , Feminino , Alimentos Fortificados , Humanos , Incidência , Ferro/sangue , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Gravidez/sangue , Prevalência
9.
Med Pr ; 42(3): 185-91, 1991.
Artigo em Polonês | MEDLINE | ID: mdl-1806757

RESUMO

The work verifies data gathered by Occupational Hygiene departments of Sanitary-Epidemiological Stations about workers exposure to chromium compounds in the processing of chrome iron ore. Research showed that 7 plants were involved in the processing of chrome iron ore and that the number of workers directly employed in the process amounted to 215-230. About 150 workers were exposed to high concentrations of chromium compounds which exceeded hygienic standards. All of them were employed only in metallurgical plants. The remaining 80-100 workers subjected to the study exposed to relatively low chromium concentrations were employed in chemical plants and refractory materials plants.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Ligas/toxicidade , Cromatos/toxicidade , Cromo/toxicidade , Ferro/toxicidade , Metalurgia/normas , Ligas/síntese química , Ligas/normas , Cromatos/normas , Cromo/normas , Humanos , Ferro/normas , Concentração Máxima Permitida , Polônia
10.
Rocz Panstw Zakl Hig ; 42(1): 33-40, 1991.
Artigo em Polonês | MEDLINE | ID: mdl-1788510

RESUMO

Studies on the content of macrominerals in daily diets reconstructed in 1988 on the basis of the analysis of family budgets in 1986 carried out by the Central Statistical Bureau were carried on. Two social groups i.e. manual and mental workers with medium income were considered. The diets were prepared for 5 regions (Warszawa, Lublin, Olsztyn, Poznan, Wroclaw). According to the studies the requirements for calcium and magnesium were met in about 70% and those for iron in about 84%. The content of potassium in the diets was in the range of recommended allowances while the phosphorus exceeded the allowances by about 20-30%. The comparison of the presently studied diets with the ones from 1973, 1980, 1981 showed a lower degree of realization of the recommended intake of calcium and magnesium in 1986. The content of studied minerals in the diets was usually similar in all five regions.


Assuntos
Cálcio/administração & dosagem , Serviços de Dietética/normas , Ferro/administração & dosagem , Magnésio/administração & dosagem , Fenômenos Fisiológicos da Nutrição , Serviços de Saúde do Trabalhador/normas , Fósforo/administração & dosagem , Potássio/administração & dosagem , Cálcio/normas , Alimentos Fortificados/normas , Humanos , Ferro/normas , Magnésio/normas , Valor Nutritivo , Fósforo/normas , Polônia , Potássio/normas
12.
Anal Sci ; 28(12): 1171-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23232237

RESUMO

A certified reference material (CRM) for trace cadmium and other elements in brown rice flour was developed at the National Metrology Institute of Japan (NMIJ). The CRM was provided as a dry powder after drying and frozen pulverization of fresh brown rice obtained from a Japanese domestic market. Characterization of the property value for each element was carried out exclusively by NMIJ with at least two independent analytical methods, including inductively coupled plasma mass spectrometry (ICP-MS), ICP high-resolution mass spectrometry, isotope-dilution ICP-MS, ICP optical emission spectrometry, and graphite-furnace atomic-absorption spectrometry. Property values were provided for six elements (Mn, Fe, Cu, Zn, As, and Cd). The concentration range of the property values was from 0.280 mg kg(-1) of As to 31.8 mg kg(-1) of Zn. The combined relative standard uncertainties of the property values were estimated by considering the uncertainties of the homogeneity, characterization, difference among analytical methods, dry-mass correction factor, and calibration standard. The range of the relative combined standard uncertainties was from 1.1% of Zn to 1.6% of As.


Assuntos
Cádmio/análise , Farinha/análise , Oryza/química , Arsênio/análise , Arsênio/normas , Cádmio/normas , Calibragem , Cobre/análise , Cobre/normas , Farinha/normas , Ferro/análise , Ferro/normas , Manganês/análise , Manganês/normas , Espectrometria de Massas , Zinco/análise , Zinco/normas
17.
Contrast Media Mol Imaging ; 3(6): 223-32, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19072771

RESUMO

Small particles of iron oxide (SPIO) and ultrasmall particles of iron oxide (USPIO), inducing a strong negative contrast on T(2) and T(2)*-weighted MR images, are the most commonly used systems for the magnetic labeling of cultured cells and their subsequent detection by magnetic resonance imaging (MRI). The purpose of this work is to study the influence of iron incubation concentration, nanoparticle size and nanoparticle coating on the magnetic labeling and the viability of non-phagocytic adherent cells in culture. The magnetic labeling of 3T6 fibroblasts was studied by T(2)-weighted MRI at 4.7 T and by dosing-or cytochemical revealing-of iron through methods based on Perl's Prussian blue staining. Cells were incubated for 48 h with increasing iron concentrations of SPIO (25-1000 microg Fe/ml Endorem. Sinerem, a USPIO (20-40 nm) coated with neutral dextran, and Resovist (65 nm), a SPIO bearing an anionic carboxydextran coating, were compared with Endorem (dextran-coated, 80-150 nm) as magnetic tags. The iron loading of marrow stromal cell primary cultures (MSCs) isolated from rat femurs was compared with that of 3T6 fibroblasts. The SPIO-labeling of cells with Endorem was found to be dependent on the iron incubation concentration. MSCs, more sparsely distributed in the culture, exhibited higher iron contents than more densely populated 3T6 fibroblast cultures. A larger iron loading was achieved with Resovist than with Endorem, which in turn was more efficient than Sinerem as a magnetic tag. The magnetic labeling of cultured non-phagocytic adherent cells with iron oxide nanoparticles was thus found to be dependent on the relative concentration of the magnetic tag and of the cells in culture, on the nanoparticle size, and on the coating type. The viability of cells, estimated by methods assessing cell membrane permeability, was not affected by magnetic labeling in the conditions used in this work.


Assuntos
Meios de Contraste/química , Compostos Férricos , Nanopartículas , Coloração e Rotulagem/métodos , Animais , Células da Medula Óssea , Sobrevivência Celular , Células Cultivadas , Meios de Contraste/normas , Dextranos , Óxido Ferroso-Férrico , Fibroblastos/citologia , Fibroblastos/metabolismo , Ferro/normas , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita , Camundongos , Nanopartículas/química , Óxidos/normas , Ratos , Kit de Reagentes para Diagnóstico/normas , Coloração e Rotulagem/normas , Células Estromais/metabolismo
18.
Anal Bioanal Chem ; 382(1): 239-42, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15900479

RESUMO

An electrothermal atomic absorption spectrometric method (ET-AAS) was developed for the direct determination of iron in intestinal Caco-2 cells after studying cell viability and proliferation using 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT test). Zeeman background correction and end-capped graphite tubes with L'vov platforms were used. Samples were dissolved in dimethylsulfoxide (DMSO) and pipetted directly into the graphite tube. The preashing, pretreatment and atomization steps were optimized. The temperatures selected were 600, 1200, and 2100 degrees C, respectively. Stability measurements were performed using iron standard solutions in DMSO on the one hand and acidified cell solutions on the other. Direct measurement and standard addition were compared in order to determine possible influences of the matrix. The low detection limit of the ET-AAS method (1.3 microg/L or 3.3 microg/g) combined with the small sample quantities required are ideal for the determination of iron in cells due to the low iron content and the limited growth area of the cells. The method was developed for iron uptake studies for toxicological purposes.


Assuntos
Ferro/análise , Espectrofotometria Atômica/métodos , Células CACO-2 , Calibragem , Humanos , Ferro/normas , Padrões de Referência , Sensibilidade e Especificidade
19.
J Assoc Off Anal Chem ; 58(5): 902-5, 1975 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1158832

RESUMO

Eight laboratories conducted a test for the estimation of the bioavailability of iron from 4 sources, using depleted male albino rats. Ferrous sulfate was used as the reference standard. Ferric orthophosphate was found to have a relative biological value of 11 (range 6-22), an old sample of hydrogen-reduced iron 27 (range 15-41), and ferric citrate 96 (range 75-125). Good results were obtained with a simplified basal diet prepared without ingredients that had previously contributed variable quantities of iron. There was no apparent advantage in using the change in hemoglobin during the repletion period instead of the final homoglobin value as the criterion of response to iron supplements. Several statistical treatments of the data yielded similar conclusions regarding relative biological values of the iron sources.


Assuntos
Disponibilidade Biológica , Biofarmácia , Ferro/normas , Animais , Compostos Férricos/análise , Compostos Ferrosos/análise , Hemoglobinometria , Masculino , Compostos Organometálicos/análise , Ratos
20.
Clin Chem ; 36(10): 1789-92, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2170060

RESUMO

The manual Reference Method of the Centers for Disease Control for serum iron (CDC/RM/Fe) and a semiautomated adaptation of it were used to evaluate two working methods: one, a detergent solubilization procedure for the Roche Cobas-Bio analyzer, the other, the Kodak Ektachem 700 procedure, based on dry-film technology. The CDC/RM/Fe and its semiautomated version gave essentially the same results for 40 sera from hospital patients. This semiautomated version was in turn compared with the two working procedures in a study involving 200 patients. Each of the working methods correlated well with the semiautomated CDC/RM/Fe method. Separate recovery and interference studies indicated satisfactory analytical recovery of iron in all cases, but the detergent solubilization method was found to be susceptible to interference by hemoglobin, lipemia, and bilirubin.


Assuntos
Análise Química do Sangue/normas , Ferro/sangue , Autoanálise/métodos , Autoanálise/normas , Centers for Disease Control and Prevention, U.S. , Humanos , Ferro/normas , Padrões de Referência , Estados Unidos
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