Abstract. Dracorhodin perchlorate (Dp), a synthetic analogue of the antimicrobial anthocyanin red pigment, has recently been shown to induce apoptotic cell death in various types of cancer cells. Yet, the inhibitory effect of Dp on human glioma cells remains uninvestigated. Therefore, in the present study, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry were used to detect cell viability and cell cycle progression in glioma U87MG and T98G cells, respectively. Annexin V-FITC/propidium iodide double staining and JC-1 staining were separately applied to determine cellular apoptosis and mitochondrial membrane potential damage in the cells. The expression levels of associated proteins involved in cell cycle progression and apoptosis were measured by western blotting. The activities of caspase-9/-3 were determined by Caspase-Glo-9/3 assay. The results indicated that Dp treatment significantly inhibited cell proliferation in a dose-and time-dependent manner, and blocked cell cycle progression at the G 1 /S phase in the U87MG and T98G cells via the upregulation of p53 and p21 protein expression, and simultaneous downregulation of Cdc25A, Cdc2 and P-Cdc2 protein expression. Additionally, Dp treatment led to the loss of cellular mitochondrial membrane potential, and the release of cytochrome c, and strongly induced the occurence of apoptosis. Increased expression levels of Bim and Bax protein and the downregulated expression of Bcl-2 protein were observed. Caspase-9/-3 were activated and their activities were elevated after Dp treatment. These findings indicate that Dp inhibits cell proliferation, induces cell cycle arrest and apoptosis in glioma cells, and is a possible candidate for glioma treatment. IntroductionBrain glioma is the most common form of neural malignancy in the nervous system. High grade glioma is the leading cause of brain cancer-related mortality due to its high invasive ability and malignant proliferation (1,2). Glioma incidence accounts for approximately 40-50% of all intracranial tumors (3). Although current treatment has modestly improved patient survival, patients with gliomas still have a very poor prognosis and low cure rates. It was reported that patients with anaplastic astrocytoma have a median survival of 2-3 years, but for those with more aggressive glioblastomas, the median survival is only 12-15 months (4,5). Currently, surgery is considered as an important initial clinical approach for glioma, yet it is difficult to completely remove diffuse tumor cells. Radiotherapy and chemotherapy after initial surgical resection are regarded as an effective therapeutic plan to prevent disease recurrence (6). However, most attempts to increase the efficacy of radiotherapy and chemotherapy are hampered by unacceptable late toxicities (7). In addition, the drug-resistance of tumor cells finally results in the abrogation of the effects of current chemotherapeutic agents (8). Accordingly, to improve the prognosis and quality of life of patients with gliomas, the ...

The rapid development of Internet of Things (IoT) technology has brought great convenience to people's life. However, the security protection capability of IoT is weak and vulnerable. Therefore, more protection needs to be done for the security of IoT. The paper proposes an intrusion detection method for IoT based on multi GBDT feature reduction and hierarchical traffic detection model. Firstly, GBDT is used to filter the features of IoT traffic data sets BoT-IoT and UNSW-NB15 to reduce the traffic feature dimension. At the same time, in order to improve the reliability of feature filtering, this paper constructs multiple GBDT models to filter the features of multiple sub data sets, and comprehensively evaluates the filtered features to find out the best alternative features. Then, two neural networks are trained with the two data sets after dimensionality reduction, and the traffic will be detected with the trained neural network. In order to improve the efficiency of traffic detection, this paper proposes a hierarchical traffic detection model, which can reduce the computational cost and time cost of detection process. Experiments show that the multi GBDT dimensionality reduction method can obtain better features than the traditional PCA dimensionality reduction method. Besides, the use of dual data sets improves the comprehensiveness of the IoT intrusion detection system, which can detect more types of attacks, and the hierarchical traffic model improves the detection efficiency of the system.

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