The derivatization towards the hydroxyl groups of steroid environmental endocrine disrupting chemicals,such as estrone(E1),17β-estradiol(E2),estriol(E3) and 17α-ethynylestradoil( EE2),with A,O-bis (trimethylsilyl) trifluoroacetamide ( BSTFA ) as derivatization reagent followed by gas chromatography-mass spectrometry(GC-MS) was studied. The effects of the amount of BSTFA,derivatization temperature and time on the derivatization of target compounds,as well as the stability of steroid derivatives,calibration curves,instrumental quantification limits were investigated. The cleavage mechanism of steroid derivatives characteristic fragment ions was also interpreted. The results showed that better derivatization results were obtained when the amount of BSTFA was 25 μL for 100 μL steroids standard mix solution at 0.01 g/L;it is unnecessary to heating in the derivatization,better results were obtained when the steroids were derivatized with BSTFA at room temperature (20℃) for 10 min. The derivatives of target compounds were stable because their relative response factors(RRFs) had no observable change when deposited at -20℃ for 48 h. Under the optimal conditions,good linear correlation was obtained and the instrumental quantification limit was 0. 3μg/L for E1 and E2,while it was 5μg/L for EE2 and E3.

OBJECTIVETo observe the status of iron deposition in patient with β thalassemia major, and to formulate appropriate treatment strategies.

METHODThe data of status of transfusion and chelation in 135 patients aged from 6 years and 4 months to 17 years and 11 months with β thalassemia major were collected and analyzed. Serum ferritin levels were determined and cardiac and hepatic iron deposition was determined using MRI T2(*) technology.

RESULTOf the 135 cases studied, 66 were male, and 69 were female, their average age was 12.1 years. Serum ferritin (SF) was determined for 111 cases, it varied from 1 086.8 µg/L to 15 011.5 µg/L. Among them, 16 cases had SF level <2 000 µg/L (14.5%) , in 41 cases SF were between 2 000 and 4 000 µg/L (36.0%) ;in 54 cases SF >4 000 µg/L (48.7%) . Liver MRI T2(*) results showed that in only 8 cases (5.9%) iron content in the liver was in normal range, 19 cases (14.9%) showed mild liver iron deposition;34 (25.2%) moderate and 74 (54.8%, the youngest one was only 6 years and 4 months of age) had severe iron deposition respectively. Cardiac MRI T2(*) showed that in 89 cases (65.9%) iron content in the heart was in normal range;19 cases (14.1%) had mild cardiac iron deposition and 27 (20.0%) presented severe iron deposition (the youngest one was only 9 years and 3 months of age) . SF level was obviously related to liver and cardiac iron deposition (MRI T2(*)) r and P value were -0.284, 0.003 and -0.374, 0.000 respectively. In 108 cases regular transfusion and chelation were delayed due to financial problem. The late and insufficient dosage administered and irregular chelation caused the higher SF level and the severe iron deposition.

CONCLUSIONThe survival status of β thalassemia major in China is worrisome. Majority of them had not received regular transfusion and chelation. Liver and cardiac iron deposition occur early and had a high incidence.

Adolescent ; Child ; Female ; Ferritins ; blood ; Humans ; Iron ; metabolism ; Iron Chelating Agents ; adverse effects ; therapeutic use ; Iron Overload ; epidemiology ; etiology ; Liver ; metabolism ; Magnetic Resonance Imaging ; Male ; Myocardium ; metabolism ; Radiography ; Retrospective Studies ; Transfusion Reaction ; beta-Thalassemia ; diagnostic imaging ; metabolism ; therapy