Cryptotanshinone Induces Apoptosis of HL-60 Cells via Mitochondrial Pathway

Purpose: To test the effect of Cryptotanshinone (CPT), a natural  compound isolated from the plant Salvia miltiorrhiza Bunge, on human leukemic cell lines (HL-60).Methods: HL-60 cells were treated with CPT. Cell growth inhibition (%) was quantitated using MTT assay. Apoptosis detection with Annexin  V-FITC/propidium iodide staining was followed by flow cytometry. Caspase-3, caspase-8, and caspase-9 colorimetric assay kit was used to determine caspase protease activity. Loss of mitochondrial membrane potential was examined by flow cytometry with JC-1 staining. Bax, PARP, p53, p21 and cytochrome C were determined using Western blot.Results: Morphologic assessment, Annexin V-FITC/propidium iodide  staining results and sub-G1 percentage indicate that the cytotoxic effect of CPT was mediated by induction of apoptosis. Furthermore, increased Bax expression, decreased Bcl-2 expression, loss of mitochondria membranepotential (MMP), release of cytochrome C, activation of caspase enzyme, cleavage of PARP and accumulation of p53 and p21 were detected during the apoptotic process. Caspase inhibitor partially abrogated CPT-induced apoptosis.Conclusion: The results show that CPT induced apoptosis of HL-60 cell lines by mitochondria pathway, and suggest that CPT may serve as a potential therapy for leukemia.Keywords: Cryptotanshinone, Salvia miltiorrhiza Bunge, Caspase,  Membrane potential, Mitochondrial, Apoptosis, Leukemia, Cytochrome C, Cell cycl

Acceleration disturbances due to local gravity gradients in ASTROD I

The Astrodynamical Space Test of Relativity using Optical Devices (ASTROD) mission consists of three spacecraft in separate solar orbits and carries out laser interferometric ranging. ASTROD aims at testing relativistic gravity, measuring the solar system and detecting gravitational waves. Because of the larger arm length, the sensitivity of ASTROD to gravitational waves is estimated to be about 30 times better than Laser Interferometer Space Antenna (LISA) in the frequency range lower than about 0.1 mHz. ASTROD I is a simple version of ASTROD, employing one spacecraft in a solar orbit. It is the first step for ASTROD and serves as a technology demonstration mission for ASTROD. In addition, several scientific results are expected in the ASTROD I experiment. The required acceleration noise level of ASTROD I is 10^-13 m s^-2 Hz^{-1/2} at the frequency of 0.1 mHz. In this paper, we focus on local gravity gradient noise that could be one of the largest acceleration disturbances in the ASTROD I experiment. We have carried out gravitational modelling for the current test-mass design and simplified configurations of ASTROD I by using an analytical method and the Monte Carlo method. Our analyses can be applied to figure out the optimal designs of the test mass and the constructing materials of the spacecraft, and the configuration of compensation mass to reduce local gravity gradients.Comment: 6 pages, presented at the 6th Edoardo Amaldi Conference (Okinawa Japan, June 2005); to be published in Journal of Physics: Conference Serie

AC-PROT: An Access Control Model to Improve Software-Defined Networking Security

© 2017 IEEE. The logically-centralized controllers have largely operated as the coordination points in software-defined networking(SDN), through which applications submit network operations to manage the global network resource. Therefore, the validity of these network operations from SDN applications are critical for the security of SDN. In this paper, we analyze the mechanism that generates network operations in SDN, and present a fine-grained access control model, called Access Control Protector(AC-PROT),that employs an attribute-based signature scheme for network applications. The simulation result demonstrates that AC-PROT can efficiently identify and reject unauthorized network operations generated by applications

Raman spectroscopy of epitaxial graphene on a SiC substrate

The fabrication of epitaxial graphene (EG) on SiC substrate by annealing has attracted a lot of interest as it may speed up the application of graphene for future electronic devices. The interaction of EG and the SiC substrate is critical to its electronic and physical properties. In this work, Raman spectroscopy was used to study the structure of EG and its interaction with SiC substrate. All the Raman bands of EG blue shift from that of bulk graphite and graphene made by micromechanical cleavage, which was attributed to the compressive strain induced by the substrate. A model containing 13 x 13 honeycomb lattice cells of graphene on carbon nanomesh was constructed to explain the origin of strain. The lattice mismatch between graphene layer and substrate causes the compressive stress of 2.27 GPa on graphene. We also demonstrate that the electronic structures of EG grown on Si and C terminated SiC substrates are quite different. Our experimental results shed light on the interaction between graphene and SiC substrate that are critical to the future applications of EG.Comment: 20 pages, 5 figure

Documentation of a new hypotrich species in the family Amphisiellidae, Lamtostyla gui n. sp. (Protista, Ciliophora) using a multidisciplinary approach

An integrated approach considering both morphologic and molecular data is now required to improve biodiversity estimations and provide more robust systematics interpretations in hypotrichs, a highly differentiated group of ciliates. In present study, we document a new hypotrich species, Lamtostyla gui n. sp., collected from Chongming wetland, Shanghai, China, based on investigations using living observation, protargol staining, scanning and transmission electron microscopy, and gene sequencing. The new species is mainly recognized by having a short amphisiellid median cirral row composed of four cirri, three frontoventral cirri, three dorsal kinetids, four to eight macronuclear nodules, and small colorless cortical granules distributed as rosettes around dorsal bristles. Transmission electron microscope observation finds the associated microtubules of cirri and pharyngeal discs of L. gui are distinct from those in other hypotrichs. Morphogenesis of this species indicates that parental adoral membranelles retained intact or partial renewed is a potential feature to separate Lamtostyla granulifera-group and Lamtostyla lamottei-group. Phylogenetic analysis based on small subunit ribosomal RNA (rRNA) gene shows that this molecular marker is not useful to resolve phylogenetic relationships of the genus Lamtostyla, as well as many other hypotrichous taxa. We additionally characterize the internal transcribed spacers (ITS) region and the almost complete large subunit rRNA, which will be essential for future studies aimed at solving phylogenetic problems of Lamtostyla, or even the family Amphisiellidae. As a final remark, the critical screening of GenBank using ITS genes of our organism allows us to recognize a large amount of hypotrichous sequences have been misclassified as fungi. This observation suggests that hypotrichs could be frequently found in fungi-rich environment and overlooked by fungal specialists

Attack and Defence of Ethereum Remote APIs

© 2018 IEEE. Ethereum, as the first Turing-complete blockchain platform, provides various application program interfaces for developers. Although blockchain has highly improved security, faulty configuration and usage can result in serious vulnerabilities. In this paper, we focus on the security vulnerabilities of the official Go-version Ethereum client (geth). The vulnerabilities are because of the insecure API design and the specific Ethereum wallet mechanism. We demonstrate attacks exploiting these vulnerabilities in an Ethereum testbed. The vulnerabilities are confirmed by the scanning results on the public Internet. Finally, corresponding countermeasures against attacks are provided to enhance the security of the Ethereum platform