Thalassemia is the most common hereditary

Paediatrica Indonesiana May ‡ VOLUME 52 NUMBER 3 Original Article Variables associated with malondialdehyde level in thalassemia major patien...
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Paediatrica Indonesiana May ‡

VOLUME 52

NUMBER 3

Original Article

Variables associated with malondialdehyde level in thalassemia major patients Arum Gunarsih, Pustika Amalia, Imam Boediman

Abstract Background Thalassemia is the most common hereditary haemolytic anaemia in the world, including in Indonesia. The main treatment for thalassemia is regular transfusions, but these are known to cause iron overload. Moreover, iron overload in E-thalassemia patients generates oxygen free radicals and peroxidative lipid injury. Ferritin serum concentration is used as indirect measurement of iron overload. Malondialdehyde (MDA), a terminal compound of lipid peroxidation, is used as an index of oxidative stress status. Objective To assess the correlation between iron overload (serum ferritin level) and MDA as a marker of oxidative stress in thalassemia major patients. Methods This cross-sectional study was conducted at Cipto Mangunkusumo +RVSLWDO -DNDUWD IURP 0D\-XQH  6XEMHFWV were thalassemia major patients (homozygous E-thalassemia or E-thalassemia/HbE) who received regular blood transfusions, ironchelation, and vitamin E as an antioxidant. Data was collected by history-taking, physical examination, medical records, and questionnaires. Blood specimens were drawn from the thalassemia major subjects before transfusion and examined for serum ferritin and MDA levels. Results Fifty-five subjects with thalassemia major (34 homozygous EWKDODVVHPLD DQG  E-thalassemia/HbE) were included in our VWXG\0HDQVHUXPIHUULWLQOHYHOZDV 6' —J/DQG PHDQ0'$OHYHOZDV 6' QPROP/1RFRUUHODWLRQ was found between serum ferritin and MDA levels in thalassemia PDMRUVXEMHFWV U 3  $VDGGLWLRQDOUHVXOWVWKLVVWXG\ also showed no correlation between MDA to reguler vitamin E FRQVXPSWLRQ U 3  DVZHOODV0'$DQGQXWULWLRQDO VWDWXV U 3   Conclusion There was no correlation between serum ferritin level and plasma MDA level in thalassemia major subjects, no correlations between MDA and regular vitamin E consumption, as well as MDA and nutritional status. [Paediatr Indones. 2012;52:125-31]. Keywords: thalassemia, oxidative stress, ferritin, malondialdehyde

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halassemia is the most common hereditary chronic hemolytic anaemia in the world, including in Indonesia. Thalassemia and hemoglobinopathies are caused by impaired synthesis of D- or E-globin chains. The number of thalassemia patients in Indonesia has increased.4 $V RI 'HFHPEHU  WKHUH ZHUH  SDWLHQWV registered at the Thalassemia Centre, Department of Child Health, Cipto Mangunkusumo Hospital (DCHCMH), Jakarta.5 3DWLHQWVZLWKE-thalassemia major often receive regular blood transfusions, leading to iron overload. Excess iron deposits in tissues and organs are known to generate oxygen free radicals, which then react ZLWKFHOOXODUSKRVSKROLSLGPHPEUDQHV3HUR[LGDWLYH tissue injury is detectable in these patients, and results in damage and failure of organs. An abundance of free radicals requires an optimal antioxidant system to persist in thalassemia patients. The level of cellular antioxidant vitamins, such as vitamin A, C, and E, were found to be considerably lower in thalassemic patients compared to normal subjects.  These results suggest major antioxidant consumption in thalassemic

)URP WKH 'HSDUWPHQW RI &KLOG +HDOWK 0HGLFDO 6FKRRO 8QLYHUVLW\ RI Indonesia, Cipto Mangunkusumo Hospital, Jakarta, Indonesia. Reprint requests to: Arum Gunarsih, Department of Child Health, 0HGLFDO 6FKRRO 8QLYHUVLW\ RI ,QGRQHVLD &LSWR 0DQJXQNXVXPR +RVSLWDO-O'LSRQHJRUR1R-DNDUWDIndonesia. 7HO (PDLO[email protected]

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Arum Gunarsih et al: Malondialdehyde level in thalassemia major patients

patients with iron overload from continuous blood transfusions or oxidative stress. 6HUXP IHUULWLQ LV D FRPPRQ LQGLFDWRU RI LURQ storage.  MDA, a terminal compound of lipid peroxidation, is used widely as an index of oxidative status. Increased plasma MDA levels have been observed in patients affected by E-thalassemia major. This substrate also causes cell damage and death, or genetic mutations.24 This study was aimed to assess the correlation between iron overload and MDA as a marker of oxidative stress in thalasemia major patients.

Methods This cross-sectional study was performed in the outpatient clinic at the Thalassemia Centre, DCH-CMH, Jakarta in 0D\-XQH6XEMHFWVZHUHVHOHFWHGE\FRQVHFXWLYH sampling of thalassemia major patients. The inclusion criteria comprised of children diagnosed with thalassemia PDMRU ZKR KDG UHFHLYHG WUDQVIXVLRQV PRUH WKDQ  times or had been given iron-chelation treatment. Thalassemia major patients with acute or chronic infection, including hepatitis B or C, or hypersplenism were excluded. Based on the calculated required sample VL]HRXUVWXG\LQFOXGHGVXEMHFWVUDQJLQJIURP years in age. Informed consent was obtained from all of the participants/parents and the study was approved by the Ethics Committee of the University of Indonesia 0HGLFDO6FKRRO'DWDRQDGKHUHQFHWRYLWDPLQ(DQG iron chelating agent consumption was collected by questionnaire and medical records.25 Blood sample was analyzed for serum lipid peroxide by quantitative assay of MDA using thiobarbituric acid reactive substances DQGD89VSHFWURPHWHU 6KLPDG]X&RUSRUDWLRQ-DSDQ  at the Biochemistry Laboratory of the CMH, Jakarta.26 The serum ferritin quantitative test was based on a solid phase enzyme-linked immunosorbent assay, using D&REDV.LWDWWKH&OLQLFDO3DWKRORJ\/DERUDWRU\RIWKH CMH, Jakarta.3DWLHQWV·EORRGZDVGUDZQMXVWEHIRUH EORRGWUDQVIXVLRQ6WXG\UHVXOWVZHUHDQDO\]HGE\6366 YHUVLRQ'LIIHUHQFHVZHUHFRQVLGHUHGVLJQLILFDQWIRU 3$OOUHVXOWVDUHH[SUHVVHGDVPHDQ+ standard GHYLDWLRQ 6'  7KH UHODWLRQ EHWZHHQ VHUXP IHUULWLQ concentrations and MDA level was determined with 3HDUVRQ·V FRHIILFLHQW FRUUHODWLRQ /LQHDU UHJUHVVLRQ analysis was used to determine a correlation between MDA and other variables.

126‡Paediatr Indones, Vol. 52, No. 3, May 2012

Results Fifty-five subjects diagnosed with E-thalassemia major were consecutively recruited for this study. Characteristics of the subjects are presented in Table 1. The mean MDA level of all subjects in this VWXG\ZDVQPROP/ 6' ZLWKDUDQJH RIQPROP/0HDQIHUULWLQVHUXPOHYHO ZDV—J/ 6' ZLWKDUDQJHRI —J/ )HUULWLQ VHUXP DQG 0'$ OHYHOV LQ WKLV VWXG\ ZHUHQRWFRUUHODWHG U 3  DVVKRZQ in Figure 1. Older subjects had higher MDA levels than younger subjects as shown in Table 2. Homozygous ß-thalassemia subjects had higher MDA levels than ‰WKDODVVHPLD+E( VXEMHFWV 6XEMHFWV ZKR XVHG deferasirox as an iron-chelating agent, had a length RI LOOQHVV UDQJHG EHWZHHQ  PRQWKV DQG ZHUH malnourished also had higher levels of MDA than subjects in other categories. Table 4 shows the bivariate analysis of the above variables with MDA level. Table 1. Characteristics of subjects Characteristics Sex Male Female Thalassemia type Homozygous E-thalassemia E-thalassemia/HbE Age, years 10 Age at diagnosis, years 2 Nutritional status based on MUAC Well-nourished Undernourished Malnourished Iron-chelation type Desferoxamine Deferiprone Deferasirox No iron-chelation Transfusion frequency, times per year < 10 10-15 > 15 Pre-transfusion hemoglobin, g/dL 8 MUAC: mid-upper arm circumference

Number (%) n=55 36 (65.4) 19 (34.6) 34 (61.8) 21 (38.2) 7 (12.7) 27 (49.1) 21 (38.2) 24 (43.6) 19 (34.6) 12 (21.8) 18 (32.7) 25 (45.5) 12 (21.8) 12 (21.8) 40 (72.7) 2 (3.6) 1 (1.8) 23 (41.8) 29 (52.7) 3 (5.5) 8 (14.5) 45 (81.8) 2 (3.6)

Arum Gunarsih et al: Malondialdehyde level in thalassemia major patients

Figure 1. Correlation of ferritin and MDA levels (r=0.147, P= 0.285) Notes: MDA = 2x105 ferritin + 0.569. R2 = 0.021. Table 2. Distribution of mean ferritin and MDA levels Characteristics Age (in study period) < 5 years 5-10 years  Ů[GCTU Type of thalassemia Homozygous E-thalassemia  E-thalassemia/HbE Iron-chelation type Desferoxamine Deferiprone Deferasirox Duration of disease < 24 months 25-120 months > 120 months Nutritional status (based on MUAC) Well-nourished Undernourished Severely malnourished MUAC: mid-upper arm circumference

n

Mean ferritin level (SD) μg/L

Mean MDA level (SD) nmol/mL

7 27 21

2853 (803.9) 5909 (1547.1) 4749 (2113.4)

0.52 (0.166) 0.59 (0.213) 0.75 (0.343)

34 21

3950.0 (2308) 6256.9 (1817)

0.68 (0.32) 0.59 (0.21)

12 40 2

4711.8 (2627.0) 3318.6 (1771.1) 6504.5 (2741.0)

0.74 (0.36) 0.58 (0.23) 1.19 (0.12)

10 27 18

1752.0 (878.5) 4983.8 (2171.0) 3551.7 (1958.0)

0.63 (0.14) 0.76 (0.35) 0.58 (0.26)

18 25 12

3413.4 (2306.6) 3681.4 (1789.4) 4137.0 (2529.2)

0.62 (0.21) 0.58 (0.23) 0.84 (0.36)

Nutritional status was divided into 2 categories, normal (well-nourished) and abnormal (malnourished and undernourished), so mean of the MDA level became linear. Bivariate analysis (Table 4) revealed WKUHH VWDWLVWLFDOO\ VLJQLILFDQW YDULDEOHV JHQGHU adherence to vitamin E consumption, and nutritional status. Moreover, adherence to vitamin E consumption

U 3  DQGQXWULWLRQDOVWDWXV U  3  KDGQRFRUUHODWLRQWR0'$OHYHO

Discussion The mean of age at first transfusion of our subjects was PRQWKV 6' 0RGHOOet al. reported the age

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Arum Gunarsih et al: Malondialdehyde level in thalassemia major patients Table 3. Distribution of characteristics according to thalassemia type Characteristics Mean ferritin, μg/mL (SD) Mean MDA, nmol/mL (SD) Mean age, years Mean duration of disease, months Iron-chelation type, n Desferoxamine Deferiprone Deferasirox None Nutritional status, n Well-nourished Undernourished Severely malnourished Adhered to iron-chelating agent consumption, n Adhered to vitamin E consumption, n

Homozygous E-thalassemia n = 34 3950 (2308) 0.68 (0.32) 8.5 89.8

E-thalassemia/HbE n = 21 6256.9 (1817) 0.59 (0.21) 11.4 10.8

9 22 2 1

18 3 0 0

14 13 7 15 7

4 12 5 13 7

Table 4. Correlation of various variables to mean MDA level Variables

Ferritin level Age in study period Age at diagnosis Duration of disease Sex Male Female Type of thalassemia Homozygous E-thalassemia E-thalassemia/Hb E Iron-chelation type Deferiprone Desferoxamine Adhered to iron-chelating agent consumption Poor adherence Good adherence Adhered to vitamin E consumption Poor adherence Good adherence Nutritional status Severely malnourished Undernourished Well-nourished

n

55 55 55 55

0.285 0.087 0.319 0.064

36 19

0.57 (0.22) 0.77 (0.35)

0.034

34 21

0.68 (0.32) 0.59 (0.21)

0.220

40 12

0.58 (0.23) 0.74 (0.36)

0.191

27 28

0.70 (0.33) 0.59 (0.23)

0.161

41 14

0.68(0.29) 0.51(0.19)

0.012

12 25 18

0.84 (0.36) 0.58 (0.23) 0.62 (0.21)

0.046

DWILUVWWUDQVIXVLRQWREHIRU\HDUROGVIRU \HDUROGVDQGDVKLJKDVIRU!\HDUROGV In contrast, most of our subjects were diagnosed later, since thalassemia screening is not routinely conducted in Indonesia. Consequently, blood transfusions would be received later. In our study, 25 (45.5%) subjects were underQRXULVKHGDQG  ZHUHPDOQRXULVKHGEDVHG on MUAC. Constantoulakis et al. reported that low body weight and growth impairment in ß-thalassemia

128‡Paediatr Indones, Vol. 52, No. 3, May 2012

P %QTTGNCVKQPEQGHſEKGPVVQ/&# level, r 0.147 0.233 -0.137 0.251 /GCP/&# 5&

major patients can be caused by various factors, such as chronic and severe anemia, enlarged spleen, and coexistence of other diseases, especially infections. The most common type of iron-chelating agent XVHG ZDV GHIHULSURQH   DQ DJHQW LQ ZKLFK consumption adherence is typically better than others. 2QO\RIWKDODVVHPLDPDMRUSDWLHQWVLQRXUVWXG\ used iron-chelating agents regularly. This figure was higher than that from the Thalassemia Center, DCH&0+LQ+RZHYHUWKLVLPSURYHGFRPSOLDQFH

Arum Gunarsih et al: Malondialdehyde level in thalassemia major patients

may reflect that oral iron-chelating agents were not DYDLODEOHLQ,QGRQHVLDLQ Malondialdehyde is a marker to determine the existence of oxidative stress.24 We did not compare MDA levels of thalassemia patients to normal controls. A study on MDA levels in the normal Jakarta SRSXODWLRQLQUHSRUWHGWKHPHDQOHYHOZDV 6' nmol/mL. In comparison, the mean MDA OHYHOLQWKLVVWXG\ZDVWLPHVKLJKHU7KLVUHVXOWZDV similar to a previous study that showed increased MDA in thalassemia major subjects compared to normal subjects. This situation can be explained by there being lipid peroxidation processing by auto-oxidation of unstable hemoglobin in thalassemia patients, with D-chain producing radical peroxide (O2-), erythrocyterich iron, catalyst-like copper, and iron overload that make an oxidative stress condition. Mean MDA level in thalassemia major subjects in this study was lower than in previous studies. This lower mean MDA may have been due to our use of homozygous ß-thalassemia and ß-thalassemia/HbE subjects, while other studies used normal control subjects. We found the mean MDA level in ‰WKDODVVHPLD+E( VXEMHFWV WR EH  6'   nmol/mL, lower than that of homozygous ß-thalassemia VXEMHFWV 6' QPROP/ 3! 7KLV result differs from a study by Goswami et al that showed MDA levels in homozygous ß-thalassemia subjects ZHUHORZHU> PHDQ6' QPROP/@WKDQLQ ‰WKDODVVHPLD+E( SDWLHQWV > PHDQ  6'   QPROP/@ This condition was thought to be due to iron-binding by protein, thus free radical products were not increased. There was no correlation between MDA level and VHUXPIHUULWLQOHYHOLQDOOVXEMHFWVLQWKLVVWXG\ U  3  7KLVUHVXOWGLIIHUVIURPVWXGLHVSHUIRUPHG by Livrea et al, Cighetti et al,23 and Naithani et al, possibly due to different characteristics of the subjects. Their studies all used only homozygous ß-thalassemia subjects. Furthermore, existence of other factors such as age, type of iron-chelating agent, adherence to ironchelating agent consumption, adherence to vitamin E consumption, and nutritional status, could influence the results. As presented in Table 3, homozygous ß-thalassemia subjects had a higher level of MDA than ß-thalassemia/HbE subjects, but also had lower level of serum ferritin, probably because homozygous ß-thalassemia subjects had a younger mean age,

shorter length of disease, and better nutritional status than thalassemia-ß/HbE subjects. In addition, the majority of the homozygous ß-thalassemia subjects used deferiprone. Free iron may act as a catalyst to form reactive oxygen species by Fenton reaction. However, free iron-measurement (non-transferrin-bound iron) is not a routine examination in thalassemia patients. 6HUXP IHUULWLQ OHYHO VKRZV WKH DPRXQW RI UHVHUYHG body iron, and is not a measurement of free iron. This examination is relatively easy to do and inexpensive. 6RLWKDVEHHQURXWLQHO\SHUIRUPHGWRPHDVXUHERG\ iron-content, although its value can be influenced by infection, inflammation, diet, nutritional status, liver disease, and diurnal variation. The regularity of vitamin E consumption VKRZHGQRFRUUHODWLRQZLWKOHYHORI0'$ U  3   9LWDPLQ ( GHILFLHQF\ LQ WKDODVVHPLD subjects might be caused by increased consumption as a consequence of oxidative stress and pressure on erythrocyte and other organs due to hemochromatosis. Liver damage induced by iron is related to the lack of lipid antioxidants. Mahjoub et al and Das et alreported that MDA level decreased in thalassemia subjects who received vitamin E. There was also no correlation between nutritional VWDWXV DQG 0'$ OHYHO LQ DOO VXEMHFWV U  3  1RSULRUVWXG\KDVUHSRUWHGDFRUUHODWLRQ EHWZHHQWKDODVVHPLDSDWLHQWV·QXWULWLRQDOVWDWXVDQG MDA level, but MDA level has been correlated to malnourishment. Khaled et al stated that insufficient nutritional substances increased oxidative stress.34 Nutritional substances that play a part in the free radical reaction process include vitamin E, vitamin A, vitamin C, selenium, zinc, manganese, copper, and ß-carotene. These substances act in enzymatic reactions. Malnourished children usually lack those nutritional substances.35 $ULMDQW\ LQ  IRXQG plasma zinc levels in thalassemia subjects to be low, although there was only a weak correlation between plasma zinc level and nutritional status.35 There were several limitations in this study. 6XEMHFWV ZHUH FROOHFWHG E\ FRQVHFXWLYH VDPSOLQJ As such, it was difficult to recruit subjects based on age group, gender, and other variables in balanced proportion to each other. Data on adherence to iron-chelating agent and vitamin E consumption was FROOHFWHG E\ KLVWRU\WDNLQJ DQG UHOLHG RQ SDUHQWV·

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memories, which may be subjective and prone to recall bias. We conclude that the mean MDA level was  6'   QPROP/ DQG WKH PHDQ VHUXP IHUULWLQ OHYHO ZDV  6'   —J/ 7KHUH was no correlation between MDA and ferritin serum OHYHOV U  3   7KHUH ZDV DOVR QR correlation between consumption of iron-chelating DJHQW DQG 0'$ OHYHO 3   7KLV VWXG\ DOVR revealed no correlation between adherence to vitamin (FRQVXPSWLRQDQG0'$OHYHO U 3   as well as no correlation between nutritional status DQG0'$OHYHO U 3  

References  5XQG ' 5DFKPLOHZLW] ( E-thalassemia. N Engl J Med.  2. Olivieri NF. The EWKDODVVHPLDV1(QJO-0HG   $GYDQL 5 6RUHQVRQ 6 6KLQDU ( /DQGH : 5DFKPLOHZLW] ( 6FKULHU 6/ &KDUDFWHUL]DWLRQ DQG FRPSDULVRQ RI WKH red blood cell membrane damage in severe human D- and EWKDODVVHPLD%ORRG  3UHYDOHQVLWDODVHPLDWHUXVQDLN>KRPHSDJHRQWKH,QWHUQHW@ F>FLWHG-DQXDU\@$YDLODEOHIURPhttp://www. mediaindonesia.com/print.php?ar_id=19143. 5. Data of Thalassemia Center Cipto Mangunkusumo Hospital, -DNDUWD'HFHPEHU  +LJJV'57KHLQ6/:RRGV:*7KHPROHFXODUSDWKRORJ\ RI WKH WKDODVVHPLDV ,Q :HDWKHUDOO '- &OHJJ % HGLWRUV The thalassemia syndromes. 4thHGLWLRQ/RQGRQ%ODFNZHOO 6FLHQFHS  /LYUHD0$7HVRULHUH/3LQWDXGL$0&DODEUHVH$0DJJLR A, Freisleben HJ, et al. Oxidative stress and antioxidant status LQ EHWDWKDODVVHPLD PDMRU LURQ RYHUORDG DQG GHSOHWLRQ RI OLSLGVROXEOHDQWLR[LGDQWV%ORRG  'DV1'DV&7&KDWWRSDGK\D\$'DWWD$*$WWHQXDWLRQRI oxidative stress-induced changes in thalassemic erythrocytes E\YLWDPLQ(3RO-3KDUPDFRO  .DVVDE&KHNLU$./DUDGL6)HUFKLFOL6.KHOLO$+)HNL M, Amri F, et al. Oxidant, antioxidant status and metabolic data in patients with beta-thalassemia. Clin Chim Act.   .DWWDPLV$3DSDVVRWLULRX,3DODLRORJRX'$SRVWRODNRX) Galani A, Ladis V, et al. The effects of erythropoetic activity and iron burden on hepcidin expression in patients with

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WKDODVVHPLDPDMRU+DHPDWRORJLFD  /DNVPLWDZDWL'5+DQGD\DQL68G\DQLQJVLK6..XUQLDWL9 Adhiyanto C, Hidayat J, et al. Iron status and oxidative stress in EWKDODVVHPLDSDWLHQWVLQ-DNDUWD%LR)DF  *RVZDPL.*KRVK6%DQG\RSDGK\D\0XNKHUMHH./,URQ store and free radicals in thalassemia. Indian J Clin Biochem.   *KRQH5$.XPEDU.06XU\DNDU$1.DWNDP59-RVKL NG. Oxidative stress and disturbance in antioxidant balance in beta thalassemia major. Indian J Clin Biochem.   6LPVHN ) 2]WXUN * .HPDKOL 6 (UEDV ' +DVDQRJOX $ Oxidant and antioxidant status in beta thalassemia major patients. Ankara Universitesi Tip Fakultesi Mecmuasi.   3DYORYD/(6DYRY903HWNRY+*&KDURYD,32[LGDWLYH stress in patients with EWKDODVVHPLDPDMRU6HF%LRO0HG6FL   0HUDO$7XQFHO36XUPHQ(2]EHN52]WXUN(*XQD\8 Lipid peroxidation and antioxidant status in E-thalassemia . 3HG+HP2QF  $QJHOXFFL ( %ULWWHQKDP *0 0F/DUHQ &( 5LSDOWL 0 Baronciani D, Giardiani C, et al. Hepatic iron concentration and total body iron stores in thalassemia major. N Engl J Med.   &KLJHWWL*'XFD/%RUWRQH/6DOD61DYD/)LRUHOOL*HW al. Oxidative status and malondialdehyde in E-thalassemia SDWLHQWV(XU-&OLQ,QYHV  (SRVLWR %3 %UHXHU : 6LUDQNDSUDQFKD 3 3RRWUDNR & &DEDQWFKLN =, /DELOH SODVPD LURQ LQ LURQ RYHUORDG redox activity and susceptibility to chelation. Blood.   1DLWKDQL5&KDQGUD-%KDWWDFKDUMHH-9HUPD31DUD\DQ6 3HUR[LGDWLYHVWUHVVDQGDQWLR[LGDQWHQ]\PHVLQFKLOGUHQZLWK EWKDODVVHPLDPDMRU3HGLDWU%ORRG&DQFHU  :DOWHU 3% )XQJ (% .LOOLOHD ': -LDQJ 4 +XGHV 0 Madden J, et al. Oxidative stress and inflammation in iron overloaded patients with E-thalassemia or sickle cell disease. %U-+DHPDWRO 22. Widad NM, Al-Naama LM, Hassan MK. Lipid peroxidation LQEHWDWKDODVVHPLD+DHPD  1RXURR]=DGHK-&KLDQL0.KDGDP0+$+HMD]L63ODVPD measures of oxidative stress in E-thalassemia. J Urmia Univ 0HG6FL 24. Nielsen F, Mikkelsen BB, Nielsen JB, Andersen HR, *UDQGMHDQ 3 3ODVPD PDORQGLDOGHK\GH DV ELRPDUNHU IRU R[LGDWLYH VWUHVV UHIHUHQFH LQWHUYDO DQG HIIHFWV RI OLIHVW\OH IDFWRUV&OLQ&KHP

Arum Gunarsih et al: Malondialdehyde level in thalassemia major patients 25. Data of Thalassemia Center Cipto Mangunkusumo Hospital, -DNDUWD'HFHPEHU 26. Wills, ED. Evaluation of lipid peroxidation in lipids and ELRORJLFDOPHPEUDQHV,Q6QHOO.DQG0XOORFN%HGLWRUV %LRFKHPLFDO WR[LFRORJ\ $ SUDFWLFDO DSSURDFK SUDFWLFDO DSSURDFKVHULHV/RQGRQ,5/SUHVV2[IRUGS  (QJOHELHQQH3+RRQDFNHU$99DOVDPLV-5DSLGKRPRJHQHRXV immunoassay for human ferritin in the Cobas Mira using colloidal gold as the reporter reagent. Clinical Chemistry.   0RGHOO%%HUGRXNDV97UDQVIXVLRQGHSHQGHQWWKDODVVHPLD DQHZHUD0HG-$XVW  &RQVWDQWRXODNLV0/RJRWKHWLV-/RHZHQVRQ5%$XJRXVWDNL2 (FRQRPLGRY-%RG\JURZWKLQ&RROH\·VDQHPLD KRPR]\JRXV beta thalassemia) with a correlative study as to other aspects of LOOQHVVLQFDVHV3HGLDWULFV  3XVSDVDUL 0 .DGDU JOXWDWLRQ DQG PDORQG\DOGHKLGH plasma darah mahasiswa Universitas Negeri Jakarta.





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Paediatr Indones, Vol. 52, No. 3, May 2012 ‡131