骨髓增生异常综合征红细胞酶谱测定临床应用研究

本文比较了２３例ＭＤＳ和９例ＡＡ患者４种红细胞酶的活性，除醛缩酶（ＡＬＤ）外，丙酮酸激酶（ＰＫ）、嘌呤核苷磷酸化酶（ＰＮＰ）、腺苷脱氨酶（ＡＤＡ）在ＡＡ患者均接近正常，和ＭＤＳ差异显著，尤其是ＰＫ和ＰＮＰ差异显著。据此联合检测红细胞４种酶活性，建立了ＭＤＳ和ＡＡ的判别函数式：ＰＭＤＳ＝－５．０４１０７＋０．２５６７４ＰＫ＋１．６７６５１ＡＬＤ＋０．０３４８１ＰＮＰ＋０．２５０２４ＡＤＡ，ＰＡＡ＝－７．９００３８＋０．３８４６ＰＫ＋１．４９６２１ＡＬＤ＋０．０８０５ＰＮＰ＋０．１３２３７ＡＤＡ。内部回代结果，判别敏感度ＭＤＳ为８２．６１％，ＡＡ为７７．７８％，特异度ＭＤＳ可达９０．４８％，ＡＡ仅为６３．６４％。结果表明，该判别函数式可反映红系病态造血用于临床作为ＭＤＳ诊断的辅助指标。

Inhibitory Effect of Oridonin on the Proliferation of NB4 Cells and Its Mechanism

Objective: To investigate the anti-proliferation e?ect of oridonin on leukemic NB4 cells and its mechanism. Methods: NB4 cells in culture medium in vitro were given di?erent concentrations of oridonin. The inhibitory rate of the cells were measured by MTT assay, cell apoptotic rate was detected by ?ow cytometry(FCM), morphology of cell apoptosis was observed by hoechst 33258 ?uorescence staining , and the activity of telomerase was detected using TRAP-PCR-ELISA before and after apoptosis occurred. Results: Oridonin (over 8 μmol/L) could decrease the telomerase activity, inhibit the growth of NB4 cells and induce apoptosis signi?cantly in a time- and dose-dependent manner. Marked morphological changes of cell apoptosis were observed by hoechst 33258 ?uorescence staining especially after the cells treated by oridonin for 48–60 h. Conclusion: Oridonin could inhibit the proliferation and induce the apoptosis of NB4 cells in vitro. One of the mechanisms may be the decrease of the telomerase activity of NB4 cells.

Induction of APOBEC3G in human hepatoma cells by interferon-α stimulation

To clarify the role of APOBEC3G （A3G） in cellular defense against hepatitis B virus （HBV）, the expression of A3G in normal human liver and the regulation of the A3G expression in hepatoma cell line （HuH-7） were investigated. Expression level of APOBEC3s mRNA in human liver was determined by RT-PCR. HuH-7 and HepG2 cells were treated with various concentrations of IFN-α（0 U/ml, 100 U/ml, 500 U/ml, 1000 U/ml）for 12 h. The mRNA levels were measured by a quantitative RT-PCR, the results were normalized relative to the specimens without IFN-α stimulation. Total protein of HuH-7 cells treated with various concentrations of IFN-α for 48 h was subjected to Western blot analysis. For reporter gene assay, HuH-7 cells were transfected with the reporter plasmids containing IRF- E sites and its mutants with different lengths. Then the cells were treated with or without 1200 U/ml IFN-α for additional 12 h （ 1000 U/ml） after 24 h of transfection, and the cell lysate was prepared and assayed for lueiferase activity. It was found that normal human liver expressed the rnR_NA of A3G. A3G mRNA expression in HuH-7 and HepG2 cells were up-regulated by IFN-α stimulation in a dose-depen- dent manner. Western blot analysis indicated that A3G protein expression was also enhanced by IFN-α stimulation. Sequence analysis showed the existence of putative sites of IFN regulatory factor element （IRF-E） in 5＇ region of A3G gene upstream the initiation eodon. IFN-α stimulation results in 6- to 8- fold increase in lueiferase activity in cells transfeeted with the plasmid containing IRF-E sites of the 5＇ upstream sequences, whereas luciferase activity did not change in cells transfected with the plasmid containing mutant IRF-E sites or without IRF-E sites. As a conclusion, A3G are expressed in normal human liver. A3G expression was up-regulated by IFN-α stimulation in hepatoma cells and could be involved in host defense mechanisms against HBV. IRF-E site in 5＇ region of APOBEC3G gene upstream the initiation codon plays an important role in this process.

Au nanoclusters suppress chronic lymphocytic leukaemia cells by inhibiting thioredoxin reductase 1 to induce intracellular oxidative stress and apoptosis

Chronic lymphocytic leukaemia （CLL） is a rare blood cancer that always relapses as refractory disease and eventually leads to death. To date, therapeutic options for CLL patients are scarce and there is an urgent need to develop novel chemotherapeutics that are both effective and safe. Gold-containing compounds induce a lethal oxidative and endoplasmic reticulum stress response in cultured and primary CLL cells via inhibition of thioredoxin reductase （TrxR）. However, traditional gold-containing medicines have revealed side effects during clinical applications. Therefore, safer gold-containing drugs are needed to overcome this challenge. In this study, a novel peptide templated gold cluster Au2sSv9 was synthesized and its therapeutic effect on CLL cells was evaluated. This nanocluster could induce cell apoptosis in MEC-1 cells in a dose-dependent manner which correlated with the uptake amount of clusters in cells. As expected, increasing intracellular reactive oxidative species （ROS） in MEC-1 cells was exhibited with the increase of cluster dosage. Further analyses demonstrated the underlying mechanism that the nan- oclusters suppress the activity ofTrxR1, increase the level of intracellular ROS, destroy the mitochondrial membrane potential and finally trigger the mitochondrial apoptotic pathway in MEC-1 cells. Furthermore, the direct interaction between Au2sSv9 clusters and TrxRl was confirmed for the first time by isothermal titration calorimetry. These findings explored the preclinical efficacy and potential mech- anism of gold clusters in CLL therapy and provided a fundamental reference for the development of other novel gold-containing chemotherapeutics to treat CLL.