- Email: [email protected]
Plasma selenium status in children with iron deficiency anemia
ARTICLE IN PRESS Journal of
Trace Elements in Medicine and Biology Journal of Trace Elements in Medicine and Biology 18 (2004) 193–196 www.elsevier.de/jtemb
SHORT COMMUNICATION
Plasma selenium status in children with iron deficiency anemia Metin Kaya Gu¨rgo¨zea,, A. Denizmen Aygu¨na, Ali O¨lc¸u¨cu¨b, Yasar Dog˘ana, Erdal Yılmaza a
Department of Pediatrics, Faculty of Medicine, Fırat University, Elazıg˘, Turkey Department of Chemistry, Faculty of Science and Arts, Fırat University, Elazıg˘, Turkey
b
Received 30 January 2004; accepted 26 July 2004
Abstract Iron and selenium are trace elements necessary for the maintenance of life and health. Iron deficiency is the most common nutritional deficiency among children in the world. The purpose of this study was to evaluate plasma selenium concentrations in children with iron deficiency anemia (IDA). Plasma selenium levels were investigated in 56 children with IDA and in 48 control subjects aged 1–8 years. A spectrofluorometric method was used for the determination. Plasma selenium concentrations in children with IDA (33.678.2 mg/l) were significantly lower than in the control group (56.0717.0 mg/l) (po0:001). However, there was no relation between plasma selenium, iron and hemoglobin concentrations. r 2004 Elsevier GmbH. All rights reserved. Keywords: Iron deficiency anemia; Iron; Selenium; Children
Introduction Elements such as iron and selenium are needed in the children’s diet to maintain normal growth rate and biological activities. Iron deficiency is probably the most common deficiency in humans not only in developing but also in industrialized countries [1–4]. Selenium exists naturally in food mainly as a constituent of organic compounds and the dietary intake of selenium varies in different countries [5,6]. Selenium was first known mostly for its toxic effects, but more recently has been found to act as antioxidant agent and cell protector [7,8]: Reactive oxygen and lipid peroxides cause severe damage to cells. The antioxidant enzyme glutathione peroxidase (GSH-Px) protects membranes and essential proteins from this damaging Corresponding author. Fırat U¨niversitesi Tıp Fakultesi, C¸ocuk ¨ Sag˘lıg˘ı ve Hastalıkları AD, Fırat Tıp Merkezi, 23119 Elazıg˘, Turkey. Tel.: +90 424 2333555/2338; fax: +90 424 2388096. E-mail address: [email protected] (M.K. Gu¨rgo¨ze).
0946-672X/$ - see front matter r 2004 Elsevier GmbH. All rights reserved. doi:10.1016/j.jtemb.2004.07.004
effect [9–11]. Selenium is required for the biological activity of GSH-Px and thus selenium depletion is accompanied by a decrease in GSH-Px activity. In addition, selenium affects also hematological parameters. Hemoglobin containing the ferric form of iron (Fe3+) is called methemoglobin. This form of hemoglobin does not have the ability to carry oxygen. With its antioxidative action, the selenoenzyme GSH-Px contributes to the prevention of the formation of methemoglobin [12,13]. The aim of this study was to investigate and evaluate the relation between the levels of plasma selenium and iron in children with iron deficiency anemia (IDA).
Materials and methods Subjects Fifty six children with IDA followed during a 4 month period at the department of Pediatrics (Faculty
ARTICLE IN PRESS 194
M.K. Gu¨rgo¨ze et al. / Journal of Trace Elements in Medicine and Biology 18 (2004) 193–196
Hematological parameters of both groups investi-
of Medicine, Fırat University, Elazıg˘, Turkey) were included in this study. The control group consisted of 48 healthy children matched for age and sex. Both IDA and control groups were selected among applying children at a polyclinic. 33 (59%) of the 56 children with IDA were boys and 23 (41%) were girls. In the control group, there were 29 (60%) boys and 19 (40%) girls. The age of all children (IDA and control group) ranged between 1–8 years. The mean7SD age of the IDA group was 2.171.9 years, and of the control group 2.471.3 years. To avoid effects of concurrent infections on plasma selenium and iron concentrations, children who had an infection as recently as 2 weeks before the study were excluded. Moreover, children with malnutrition were not included in the study.
Table 1. gated
Determination of hematological parameters
Table 2. Selenium and iron concentrations and parameters of iron deficiency anemia
Hemoglobin, hematocrit, white blood cells and red blood cell morphology—mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin content (MCHC), and red cell distribution width (RDW)—were measured with an automatic cell counter. Hematological parameters including transferrin saturation (serum iron/total iron binding capacity), serum albumin, and serum protein levels were determined with a Randox kit using the Olympus AU-600 system. Serum ferritin levels were determined by an automated immunoassay method (ACS 180).
Selenium determination For selenium determination, 4 ml of fasting blood were collected in plastic tubes containing anticoagulant. Plasma was separated and kept deep-frozen at 30 1C until analysis. Selenium concentrations were determined by means of the spectrofluorometric method described by Lalonde et al. [14]. All measurements were carried out using a Perkin Elmer Model 100 spectrofluometer.
Statistics Results are given as mean7SD and 95% confidence interval. The statistical evaluation was conducted using Student’s t-test and correlation tests using the SPSS program.
Results The hematological parameters of both groups are given in Table 1. Children with IDA had a statistically significantly lower mean hemoglobin level than the control group (9.671.1 and 12.670.9 g/dl, respectively,
Hemoglobin (g/dl) Hematocrit (%) MCV (mm3) MCH (g Hb/dl) MCHC (pg/cell) RDW (%)
Iron deficiency anemia group
Control group
p
9.671.1 30.972.7 63.377.2 19.573.6 30.172.5 19.373.0
12.670.9 37.073.0 75.275.0 27.272.2 33.471.2 14.172.1
o0.001 o0.001 o0.001 o0.001 o0.001 o0.001
Values are expressed as mean7standard deviation.
Iron deficiency anemia group
Control group
p
Selenium (mg/l) Mean7SD 95% confidence interval
33.678.2 32.5–34.7
56.0717.0 53.6–58.4
o0.001
Iron (mmol/l) Mean7SD 95% confidence interval
5.973.9 4.8–6.9
12.975.1 11.9–13.9
o0.001
Ferritin (mg/l) Mean7SD 95% confidence interval
5.873.0 5.4–6.2
33.5720.0 30.6–36.4
o0.001
Transferrin saturation (%) Mean7SD 7.376.2 95% confidence 6.5–8.1 interval
19.8710.8 18.4–21.2
o0.001
po0:001). Similarly, all other hematological parameters measured were significantly lower in the IDA group (po0:001). Moreover, serum iron and ferritin values as well as the transferrin saturation in children with IDA were lower than in the control group (po0:001), as shown in Table 2. On the other hand, serum protein and albumin concentrations of the children with IDA (6.970.9 and 3.970.8 g/dl, respectively) did not significantly differ from the control group (7.171.1 and 4.170.8 g/dl, respectively). The iron concentration measured was 5.973.9 mmol/l in the IDA group and 12.975.1 mmol/l in control group; the difference was statistically significant (po0:001).
ARTICLE IN PRESS M.K. Gu¨rgo¨ze et al. / Journal of Trace Elements in Medicine and Biology 18 (2004) 193–196
Control Iron deficiency anemia 40
Number of cases
35 30 25 20 15 10 5 0 <40
40-70
>70
Plasma selenium concentration (µg/l) Fig. 1. Distribution of plasma selenium concentrations.
The mean selenium concentrations in the IDA and control group were 33.678.2 and 56717.0 mg/l, respectively (Table 2). The difference between the two groups was also statistically significant (po0:001). The distribution of plasma selenium levels is presented in Fig. 1. There was no correlation between plasma selenium levels and hematological parameters or between plasma selenium levels and iron concentrations (r ¼ 0:08).
Discussion and conclusions Iron is an essential trace element and iron deficiency is most frequently observed in early childhood [16,17]. Selenium as well as the vitamins E and C, some dietary carotenoids and several other essential elements have antioxidant potential or play a role in antioxidant enzymes [8,18]. In a study involving 100 pregnant women, low total antioxidant status was found in those with iron and selenium deficiency [19]. Although GSHPx is not an iron-containing metalloprotein, previous studies on IDA have shown decreased GSH-Px activity, which is related to the selenium status [10,18,20]. Moriarty et al. [21] observed decreased serum selenium and GSH-Px levels in rats with IDA. Therefore, we suggest that selenium deficiency may accompany iron deficiency. In the present study, the mean plasma selenium concentration in the control group was 56717 mg/l.
195
In other studies from different regions of Turkey, Mengu¨bas- et al. [22] reported serum selenium concentrations of 4472 mg/l in healthy children aged 0–14 years and Hıncal et al. [23] of 87.4711.5 mg/l in healthy children aged 2 months–13 years. Geographical variations in serum selenium concentrations due to differences in soil and diet have been observed [24]. In the United States, serum selenium concentrations for healthy infants and children range from 50 to 150 mg/l [8]. In the IDA group, the mean plasma selenium concentration was 33.678.2 mg/l. In another Turkish study, Yetgin et al. [18] found serum selenium concentrations of 61.2711.0 mg/l for children aged 6 months–16 years in an IDA group and of 73.9712.6 mg/l in the control group, the difference was statistically significant (po0:001). In our study, we also observed a statistic significant difference between the plasma selenium concentration in the IDA and in the healthy control group. However, McAnulty et al. [25] found that serum selenium concentrations of a low iron stores group were not significantly different from those of the control group. Moreover, the serum selenium concentration did not change significantly from pretreatment to post-treatment with iron supplements in patients with low iron stores. In conclusion, when anemia develops due to a deficiency of iron, plasma selenium concentrations may also be low. Therefore, the selenium status of children with IDA should be taken into consideration. Selenium is recommended to be added to the treatment of IDA.
References [1] Gofin R, Palti H, Adler B. Time trends of haemoglobin levels and anaemia prevalence in infancy in a total community. Public Health 1992;106:11–8. [2] Calvo EB, Gnazzo N. Prevalence of Fe deficiency in children aged 9–24 months from a large urban area of Argentina. Am J Clin Nutr 1990;52:534–40. [3] Grant GA. Prevalence of Fe deficiency in rural pre-school children in Northern Ireland. Br J Gen Pract 1990;40:112–3. [4] Dallman PR, Yip R, Johnson C. Prevalence and causes of anemia in the United States, 1976 to 1980. Am J Clin Nutr 1984;39:437–51. [5] Olson OE, Novacek EJ, Whitehead EI, Palmer IS. Investigation on selenium in wheat. Phytochemistry 1970;9:1181–8. [6] Thorling EB, Overvad K, Geboers J. Selenium status in Europe—human data. A multicenter study. Ann Clin Res 1986;18:3–7. [7] Nancy WA. Trace elements. In: Lawrence AK editor. Clinical chemistry. Phialadelphia: Mosby; 1995. p. 746–54. [8] Litov RE, Combs Jr. GF. Selenium in pediatric nutrition. Pediatrics 1991;87:339–51.
ARTICLE IN PRESS 196
M.K. Gu¨rgo¨ze et al. / Journal of Trace Elements in Medicine and Biology 18 (2004) 193–196
[9] Bhagavan NV. In: Medical Biochemistry. Boston: Jones and Barlet Publishers; 1992. p. 875–82. [10] Yetgin S, Ciliv G, Altay C¸. Neutrophil glutathione peroxidase activity in iron deficiency anemia. Scand J Haematol 1986;36:58–60. [11] Holben DH, Smith AM. The diverse role of selenium within selenoproteins: a review. J Am Diet Assoc 1999;99: 836–43. [12] Hu ML, Spallholz JE. Dietary selenium and anilineinduced methemoglobinemia in rats. Toxicol Lett 1985; 25:205–10. [13] Chow CK, Chen CJ. Dietary selenium and age-related susceptibility of rat erythrocytes to oxidative damage. J Nutr 1980;110:2460–6. [14] Lalonde L, Jean Y, Roberts KD, Chapdelaine A, Bleau G. Fluorometry of selenium in serum or urine. Clin Chem 1982;28:172–4. [16] Go¨ktas- Y, Yıldırmak Y, Tanyer G, Dallar Y. Sag˘lıklı c¸ocuklarda demir eksiklig˘i anemisi. Ege Pediatri Bu¨lteni 1999;6:49–55. [17] Booth IW, Aukett MA. Iron deficiency anaemia in infancy and early childhood. Arch Dis Child 1997;76: 549–54. [18] Yetgin S, Hıncal F, Bas-aran N, Ciliv G. Serum selenium status in children with iron deficiency anemia. Acta Haematol 1992;88:185–8.
[19] Petukhov VI, Bykova EY, Bondare DK, et al. Iron and selenium deficiency and a demographic crisis in Russian and Latvia. Gematol Transfuziol 2001;46:18–23. [20] Rodvien R, Gillum A, Weintraub LR. Decreased glutathione peroxidase activity secondary to severe iron deficiency: a possible mechanism responsible for the shortened life span of the iron-deficient red cell. Blood 1974;43:281–9. [21] Moriarty PM, Picciano MF, Beard JL, Reddy CC. Classical selenium-dependent glutatione peroxidase expression is decreased secondary to iron deficiency in rats. J Nutr 1995;125:293–301. [22] Mengu¨bas- K, Diab NA, Go¨kmen G, Ataman OY, C¸avdar AO, Cin S- . Selenium status of healthy Turkish children. Biol Trace Elem Res 1996;54:163–72. [23] Hıncal F, Yetgin S, Atac¸eri N. Selenium status in Turkey. Biol Trace Elem Res 1989;20:161–7. [24] Lombeck I, Kasperek K, Harbisch HD, Feinendegen LE, Bremer HJ. The selenium state of healthy children. I. Serum selenium concentration at different ages; activity of glutathione peroxidase of erythrocytes at different ages; selenium content of food of infants. Eur J Pediatr 1977;125:81–8. [25] McAnulty LS, Gropper SS, McAnulty SR, Keith RE. Iron depletion without anemia is not associated with impaired selenium status in college-aged women. Biol Trace Elem Res 2003;91:125–36.
Trace Elements in Medicine and Biology Journal of Trace Elements in Medicine and Biology 18 (2004) 193–196 www.elsevier.de/jtemb
SHORT COMMUNICATION
Plasma selenium status in children with iron deficiency anemia Metin Kaya Gu¨rgo¨zea,, A. Denizmen Aygu¨na, Ali O¨lc¸u¨cu¨b, Yasar Dog˘ana, Erdal Yılmaza a
Department of Pediatrics, Faculty of Medicine, Fırat University, Elazıg˘, Turkey Department of Chemistry, Faculty of Science and Arts, Fırat University, Elazıg˘, Turkey
b
Received 30 January 2004; accepted 26 July 2004
Abstract Iron and selenium are trace elements necessary for the maintenance of life and health. Iron deficiency is the most common nutritional deficiency among children in the world. The purpose of this study was to evaluate plasma selenium concentrations in children with iron deficiency anemia (IDA). Plasma selenium levels were investigated in 56 children with IDA and in 48 control subjects aged 1–8 years. A spectrofluorometric method was used for the determination. Plasma selenium concentrations in children with IDA (33.678.2 mg/l) were significantly lower than in the control group (56.0717.0 mg/l) (po0:001). However, there was no relation between plasma selenium, iron and hemoglobin concentrations. r 2004 Elsevier GmbH. All rights reserved. Keywords: Iron deficiency anemia; Iron; Selenium; Children
Introduction Elements such as iron and selenium are needed in the children’s diet to maintain normal growth rate and biological activities. Iron deficiency is probably the most common deficiency in humans not only in developing but also in industrialized countries [1–4]. Selenium exists naturally in food mainly as a constituent of organic compounds and the dietary intake of selenium varies in different countries [5,6]. Selenium was first known mostly for its toxic effects, but more recently has been found to act as antioxidant agent and cell protector [7,8]: Reactive oxygen and lipid peroxides cause severe damage to cells. The antioxidant enzyme glutathione peroxidase (GSH-Px) protects membranes and essential proteins from this damaging Corresponding author. Fırat U¨niversitesi Tıp Fakultesi, C¸ocuk ¨ Sag˘lıg˘ı ve Hastalıkları AD, Fırat Tıp Merkezi, 23119 Elazıg˘, Turkey. Tel.: +90 424 2333555/2338; fax: +90 424 2388096. E-mail address: [email protected] (M.K. Gu¨rgo¨ze).
0946-672X/$ - see front matter r 2004 Elsevier GmbH. All rights reserved. doi:10.1016/j.jtemb.2004.07.004
effect [9–11]. Selenium is required for the biological activity of GSH-Px and thus selenium depletion is accompanied by a decrease in GSH-Px activity. In addition, selenium affects also hematological parameters. Hemoglobin containing the ferric form of iron (Fe3+) is called methemoglobin. This form of hemoglobin does not have the ability to carry oxygen. With its antioxidative action, the selenoenzyme GSH-Px contributes to the prevention of the formation of methemoglobin [12,13]. The aim of this study was to investigate and evaluate the relation between the levels of plasma selenium and iron in children with iron deficiency anemia (IDA).
Materials and methods Subjects Fifty six children with IDA followed during a 4 month period at the department of Pediatrics (Faculty
ARTICLE IN PRESS 194
M.K. Gu¨rgo¨ze et al. / Journal of Trace Elements in Medicine and Biology 18 (2004) 193–196
Hematological parameters of both groups investi-
of Medicine, Fırat University, Elazıg˘, Turkey) were included in this study. The control group consisted of 48 healthy children matched for age and sex. Both IDA and control groups were selected among applying children at a polyclinic. 33 (59%) of the 56 children with IDA were boys and 23 (41%) were girls. In the control group, there were 29 (60%) boys and 19 (40%) girls. The age of all children (IDA and control group) ranged between 1–8 years. The mean7SD age of the IDA group was 2.171.9 years, and of the control group 2.471.3 years. To avoid effects of concurrent infections on plasma selenium and iron concentrations, children who had an infection as recently as 2 weeks before the study were excluded. Moreover, children with malnutrition were not included in the study.
Table 1. gated
Determination of hematological parameters
Table 2. Selenium and iron concentrations and parameters of iron deficiency anemia
Hemoglobin, hematocrit, white blood cells and red blood cell morphology—mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin content (MCHC), and red cell distribution width (RDW)—were measured with an automatic cell counter. Hematological parameters including transferrin saturation (serum iron/total iron binding capacity), serum albumin, and serum protein levels were determined with a Randox kit using the Olympus AU-600 system. Serum ferritin levels were determined by an automated immunoassay method (ACS 180).
Selenium determination For selenium determination, 4 ml of fasting blood were collected in plastic tubes containing anticoagulant. Plasma was separated and kept deep-frozen at 30 1C until analysis. Selenium concentrations were determined by means of the spectrofluorometric method described by Lalonde et al. [14]. All measurements were carried out using a Perkin Elmer Model 100 spectrofluometer.
Statistics Results are given as mean7SD and 95% confidence interval. The statistical evaluation was conducted using Student’s t-test and correlation tests using the SPSS program.
Results The hematological parameters of both groups are given in Table 1. Children with IDA had a statistically significantly lower mean hemoglobin level than the control group (9.671.1 and 12.670.9 g/dl, respectively,
Hemoglobin (g/dl) Hematocrit (%) MCV (mm3) MCH (g Hb/dl) MCHC (pg/cell) RDW (%)
Iron deficiency anemia group
Control group
p
9.671.1 30.972.7 63.377.2 19.573.6 30.172.5 19.373.0
12.670.9 37.073.0 75.275.0 27.272.2 33.471.2 14.172.1
o0.001 o0.001 o0.001 o0.001 o0.001 o0.001
Values are expressed as mean7standard deviation.
Iron deficiency anemia group
Control group
p
Selenium (mg/l) Mean7SD 95% confidence interval
33.678.2 32.5–34.7
56.0717.0 53.6–58.4
o0.001
Iron (mmol/l) Mean7SD 95% confidence interval
5.973.9 4.8–6.9
12.975.1 11.9–13.9
o0.001
Ferritin (mg/l) Mean7SD 95% confidence interval
5.873.0 5.4–6.2
33.5720.0 30.6–36.4
o0.001
Transferrin saturation (%) Mean7SD 7.376.2 95% confidence 6.5–8.1 interval
19.8710.8 18.4–21.2
o0.001
po0:001). Similarly, all other hematological parameters measured were significantly lower in the IDA group (po0:001). Moreover, serum iron and ferritin values as well as the transferrin saturation in children with IDA were lower than in the control group (po0:001), as shown in Table 2. On the other hand, serum protein and albumin concentrations of the children with IDA (6.970.9 and 3.970.8 g/dl, respectively) did not significantly differ from the control group (7.171.1 and 4.170.8 g/dl, respectively). The iron concentration measured was 5.973.9 mmol/l in the IDA group and 12.975.1 mmol/l in control group; the difference was statistically significant (po0:001).
ARTICLE IN PRESS M.K. Gu¨rgo¨ze et al. / Journal of Trace Elements in Medicine and Biology 18 (2004) 193–196
Control Iron deficiency anemia 40
Number of cases
35 30 25 20 15 10 5 0 <40
40-70
>70
Plasma selenium concentration (µg/l) Fig. 1. Distribution of plasma selenium concentrations.
The mean selenium concentrations in the IDA and control group were 33.678.2 and 56717.0 mg/l, respectively (Table 2). The difference between the two groups was also statistically significant (po0:001). The distribution of plasma selenium levels is presented in Fig. 1. There was no correlation between plasma selenium levels and hematological parameters or between plasma selenium levels and iron concentrations (r ¼ 0:08).
Discussion and conclusions Iron is an essential trace element and iron deficiency is most frequently observed in early childhood [16,17]. Selenium as well as the vitamins E and C, some dietary carotenoids and several other essential elements have antioxidant potential or play a role in antioxidant enzymes [8,18]. In a study involving 100 pregnant women, low total antioxidant status was found in those with iron and selenium deficiency [19]. Although GSHPx is not an iron-containing metalloprotein, previous studies on IDA have shown decreased GSH-Px activity, which is related to the selenium status [10,18,20]. Moriarty et al. [21] observed decreased serum selenium and GSH-Px levels in rats with IDA. Therefore, we suggest that selenium deficiency may accompany iron deficiency. In the present study, the mean plasma selenium concentration in the control group was 56717 mg/l.
195
In other studies from different regions of Turkey, Mengu¨bas- et al. [22] reported serum selenium concentrations of 4472 mg/l in healthy children aged 0–14 years and Hıncal et al. [23] of 87.4711.5 mg/l in healthy children aged 2 months–13 years. Geographical variations in serum selenium concentrations due to differences in soil and diet have been observed [24]. In the United States, serum selenium concentrations for healthy infants and children range from 50 to 150 mg/l [8]. In the IDA group, the mean plasma selenium concentration was 33.678.2 mg/l. In another Turkish study, Yetgin et al. [18] found serum selenium concentrations of 61.2711.0 mg/l for children aged 6 months–16 years in an IDA group and of 73.9712.6 mg/l in the control group, the difference was statistically significant (po0:001). In our study, we also observed a statistic significant difference between the plasma selenium concentration in the IDA and in the healthy control group. However, McAnulty et al. [25] found that serum selenium concentrations of a low iron stores group were not significantly different from those of the control group. Moreover, the serum selenium concentration did not change significantly from pretreatment to post-treatment with iron supplements in patients with low iron stores. In conclusion, when anemia develops due to a deficiency of iron, plasma selenium concentrations may also be low. Therefore, the selenium status of children with IDA should be taken into consideration. Selenium is recommended to be added to the treatment of IDA.
References [1] Gofin R, Palti H, Adler B. Time trends of haemoglobin levels and anaemia prevalence in infancy in a total community. Public Health 1992;106:11–8. [2] Calvo EB, Gnazzo N. Prevalence of Fe deficiency in children aged 9–24 months from a large urban area of Argentina. Am J Clin Nutr 1990;52:534–40. [3] Grant GA. Prevalence of Fe deficiency in rural pre-school children in Northern Ireland. Br J Gen Pract 1990;40:112–3. [4] Dallman PR, Yip R, Johnson C. Prevalence and causes of anemia in the United States, 1976 to 1980. Am J Clin Nutr 1984;39:437–51. [5] Olson OE, Novacek EJ, Whitehead EI, Palmer IS. Investigation on selenium in wheat. Phytochemistry 1970;9:1181–8. [6] Thorling EB, Overvad K, Geboers J. Selenium status in Europe—human data. A multicenter study. Ann Clin Res 1986;18:3–7. [7] Nancy WA. Trace elements. In: Lawrence AK editor. Clinical chemistry. Phialadelphia: Mosby; 1995. p. 746–54. [8] Litov RE, Combs Jr. GF. Selenium in pediatric nutrition. Pediatrics 1991;87:339–51.
ARTICLE IN PRESS 196
M.K. Gu¨rgo¨ze et al. / Journal of Trace Elements in Medicine and Biology 18 (2004) 193–196
[9] Bhagavan NV. In: Medical Biochemistry. Boston: Jones and Barlet Publishers; 1992. p. 875–82. [10] Yetgin S, Ciliv G, Altay C¸. Neutrophil glutathione peroxidase activity in iron deficiency anemia. Scand J Haematol 1986;36:58–60. [11] Holben DH, Smith AM. The diverse role of selenium within selenoproteins: a review. J Am Diet Assoc 1999;99: 836–43. [12] Hu ML, Spallholz JE. Dietary selenium and anilineinduced methemoglobinemia in rats. Toxicol Lett 1985; 25:205–10. [13] Chow CK, Chen CJ. Dietary selenium and age-related susceptibility of rat erythrocytes to oxidative damage. J Nutr 1980;110:2460–6. [14] Lalonde L, Jean Y, Roberts KD, Chapdelaine A, Bleau G. Fluorometry of selenium in serum or urine. Clin Chem 1982;28:172–4. [16] Go¨ktas- Y, Yıldırmak Y, Tanyer G, Dallar Y. Sag˘lıklı c¸ocuklarda demir eksiklig˘i anemisi. Ege Pediatri Bu¨lteni 1999;6:49–55. [17] Booth IW, Aukett MA. Iron deficiency anaemia in infancy and early childhood. Arch Dis Child 1997;76: 549–54. [18] Yetgin S, Hıncal F, Bas-aran N, Ciliv G. Serum selenium status in children with iron deficiency anemia. Acta Haematol 1992;88:185–8.
[19] Petukhov VI, Bykova EY, Bondare DK, et al. Iron and selenium deficiency and a demographic crisis in Russian and Latvia. Gematol Transfuziol 2001;46:18–23. [20] Rodvien R, Gillum A, Weintraub LR. Decreased glutathione peroxidase activity secondary to severe iron deficiency: a possible mechanism responsible for the shortened life span of the iron-deficient red cell. Blood 1974;43:281–9. [21] Moriarty PM, Picciano MF, Beard JL, Reddy CC. Classical selenium-dependent glutatione peroxidase expression is decreased secondary to iron deficiency in rats. J Nutr 1995;125:293–301. [22] Mengu¨bas- K, Diab NA, Go¨kmen G, Ataman OY, C¸avdar AO, Cin S- . Selenium status of healthy Turkish children. Biol Trace Elem Res 1996;54:163–72. [23] Hıncal F, Yetgin S, Atac¸eri N. Selenium status in Turkey. Biol Trace Elem Res 1989;20:161–7. [24] Lombeck I, Kasperek K, Harbisch HD, Feinendegen LE, Bremer HJ. The selenium state of healthy children. I. Serum selenium concentration at different ages; activity of glutathione peroxidase of erythrocytes at different ages; selenium content of food of infants. Eur J Pediatr 1977;125:81–8. [25] McAnulty LS, Gropper SS, McAnulty SR, Keith RE. Iron depletion without anemia is not associated with impaired selenium status in college-aged women. Biol Trace Elem Res 2003;91:125–36.