The Significance and Correlation of SODD and Bel-2 Protein Expression in Acute Leukemia of Children

OBJECTIVE To explore the expression of SODD and bcl-2 proteins in bone marrow cells of children with acute leukemia （AL）, and to examine the relationship of their expression with the classification, clinical features, therapeutic effect and prognosis for AL patients.METHODS Using the SABC immunohistochemical staining method, the expression of SODD and bcl-2 proteins in the bone marrow cells of 86 AL cases was determined. Tqe patients were studied based on the following groups： 1） a first-visiting group; 2） a refractory-relapse group （some patients were sensitive, to therapy but then suffered a recurrence）; 3） a complete-remission group （CR）; 4） a high risk （HR） and 5） standard risk （SR） group; 6） a control group of patients with non-hematologica diseases.RESULTS The positive rates of SODD and bcl-2 expression in the firstvisit, refractory-relapse and CR groups were significantly higher （P〈0,05） compared to the control group. There was no significant difference in the expression of SODD or bcl-2 proteins between an acute lymphoblastic leukemia （ALL） group and acute nonlymphoblastic leukemia （ANLL） group （t=1.874, t=1.583, P〉0,05）. The positive rates of SODD and bcl-2 expression in the patients who developed complete remission after chemotherapy were significantly lower （t=2,054, t=2.703, P〈0.05） compared to the first-visit pediatric patients. The expression of the SODD protein in the refractory-relapse group was notably higher compared to the group treated initially （t=-1.081, P〈0.05）. A high expression of the bcl-2 protein was found in both the first-visit and refractory-relapse groups, with no significant difference found between the two groups （t= -1.196, P〉0.05）, whereas the percentage of bcl-2 positive cells in the refractory-relapse group （45%-87%） was significantly higher compared to the first-visit group （5%-62%）. The positive expression of the SODD and bcl-2 proteins in the high-risk （HR） group were both significantly higher than the SR group （t=-3.236, t=-3.555, P〈0.01）. The Pearson rank correlation analysis indicated that there was a positive correlation between SODD and bcl-2 expressions （P〈0.01, r=0.726）. Among the 30 AL patients in the initial treatment group, 13 patients showed negative SODD expression. These children reached a complete remission （CR） rate of 84.6% （11/13）, while in the other 17 cases with positive SODD expression, the CR rate was 64.7% （11/17）. In 8 patients with negative bcl-2 expression, the CR rate amounted to 100% （8/8）, and in 22 cases with positive bcl-2 expression, the CR rate reached 63.6% （14/22）. Statistical analysis showed that the CR rates in patients with negative expression of SODD and bcl-2 were all significantly higher （P〈0.05） compared to the patients with positive expression.CONCLUSION Both SODD and bcl-2 are closely related to the onset, progression, curative effect aqd prognosis of AL in children. The expression of SODD and bcl-2 has a definite synergistic relationship with the onset and development of AL.

磁性金纳米基因载体的制备及结合DNA研究

目的制备1种高分子材料聚乙烯亚胺（PEI）修饰的磁性金纳米粒子作为新型基因载体，观察其表征及结合DNA的能力。方法应用原位合成法合成稳定的复合磁性金纳米微粒（Au-MP-PEI）,将适量FeCl3和FeS04制备纳米磁颗粒（MP-CA）分散液，加人适量PEI溶液及氯金酸（AU-C14 ·3H20）溶液沸腾制得Au-MP-PEI;通过透射电镜观察磁性金纳米粒形态，并检测该纳米粒的粒径及电位分析;采用原液及稀释1 倍的纳米载体进行磁性金纳米载体-DNA的结合实验。结果对PEI包敷的纳米磁颗粒（MP-PEI）做磷钨酸染色后电镜扫描可见每1个团聚体都有数个纳米颗粒构成,笼罩在薄薄一层灰黑色分子下，大小在90 nm左右，而在磁性金纳米颗粒电镜照片中磁颗粒表面可见较多黑色点状颗粒，此即为合成的胶体金。通过不同浓度的金磁纳米载体凝胶阻滞电泳证明磁性金纳米原液能将DNA完全结合。结论成功制备粒径均一的磁性金纳米粒子作为新型基因载体，并且凝胶电泳实验证明该基因载体对DNA具有完全结合的能力。