1,149 research outputs found

    Clinical efficacy and safety of buyang huanwu decoction for acute ischemic stroke: a systematic review and meta-analysis of 19 randomized controlled trials

    Get PDF
    Buyang Huanwu Decoction (BHD) is a well-known traditional Chinese herbal prescription for treating stroke-induced disability. The objective of this study was to evaluate the efficacy and safety of BHD for acute ischemic stroke. A systematic literature search was performed in 6 databases until February 2012. Randomized controlled clinical trials (RCTs) that evaluate efficacy and safety of BHD for acute ischemic stroke were included. Nineteen RCTs with 1580 individuals were identified. The studies were generally of low methodological quality. Only one of the trial included death or dependency as a primary outcome measure. Only 4 trials reported adverse events. Meta-analysis showed the clinical effective rate of neurological deficit improvement favoring BHD when compared with western conventional medicines (WCM), P < 0.001. There is significant difference in the neurologic deficit score between the BHD treatment group and the WCM control group, P < 0.001. In Conclusion, BHD appears to improve neurological deficit and seems generally safe in patients with acute ischemic stroke. However, the current evidence is insufficient to support a routine use of BHD for acute ischemic stroke due to the poor methodological quality and lack of adequate safety data of the included studies. Further rigorously designed trials are required.published_or_final_versio

    Rmi1 stimulates decatenation of double Holliday junctions during dissolution by Sgs1-Top3

    Get PDF
    double Holliday junction (dHJ) is a central intermediate of homologous recombination that can be processed to yield crossover or non-crossover recombination products. To preserve genomic integrity, cells possess mechanisms to avoid crossing over. We show that Saccharomyces cerevisiae Sgs1 and Top3 proteins are sufficient to migrate and disentangle a dHJ to produce exclusively non-crossover recombination products, in a reaction termed "dissolution." We show that Rmi1 stimulates dHJ dissolution at low Sgs1-Top3 protein concentrations, although it has no effect on the initial rate of Holliday junction (HJ) migration. Rmi1 serves to stimulate DNA decatenation, removing the last linkages between the repaired and template DNA molecules. Dissolution of a dHJ is a highly efficient and concerted alternative to nucleolytic resolution that prevents crossing over of chromosomes during recombinational DNA repair in mitotic cells and thereby contributes to genomic integrity

    Identification of post-pyrite phase transitions in SiO2 by a genetic algorithm

    Get PDF
    US Department of Energy, Basic Energy Sciences, Division of Materials Science and Engineering [DE-AC02-07CH11358]; NSF [EAR-0757903, EAR-0810272, EAR-1047629, ATM-0426757]Using a first-principles genetic algorithm we predict an Fe2P phase is the first post-pyrite phase of SiO2 at low temperatures. This contrasts with a recently predicted cotunnite phase. Static enthalpy differences between these two phases are small near the transition pressure (0.69 TPa). While quasiharmonic free energy calculations predict an Fe2P--> cotunnite-type transition with increasing temperature, another phase, NbCoB type, is identified as being structurally and energetically intermediate between Fe2P and cotunnite phases. This structure suggests a possible temperature-induced gradual transformation between Fe2P and cotunnite phases. This finding would change our understanding of how planet-forming silicates, for example, MgSiO3 post-perovskite and its solid solutions, dissociate into elementary oxides at thermodynamic conditions expected in the interior of solar giants and exoplanets

    BLM and RMI1 alleviate RPA inhibition of topoIIIα decatenase activity

    Get PDF
    RPA is a single-stranded DNA binding protein that physically associates with the BLM complex. RPA stimulates BLM helicase activity as well as the double Holliday junction dissolution activity of the BLM-topoisomerase IIIα complex. We investigated the effect of RPA on the ssDNA decatenase activity of topoisomerase IIIα. We found that RPA and other ssDNA binding proteins inhibit decatenation by topoisomerase IIIα. Complex formation between BLM, TopoIIIα, and RMI1 ablates inhibition of decatenation by ssDNA binding proteins. Together, these data indicate that inhibition by RPA does not involve species-specific interactions between RPA and BLM-TopoIIIα-RMI1, which contrasts with RPA modulation of double Holliday junction dissolution. We propose that topoisomerase IIIα and RPA compete to bind to single-stranded regions of catenanes. Interactions with BLM and RMI1 enhance toposiomerase IIIα activity, promoting decatenation in the presence of RPA

    MiR-223 Suppresses Cell Proliferation by Targeting IGF-1R

    Get PDF
    To study the roles of microRNA-223 (miR-223) in regulation of cell growth, we established a miR-223 over-expression model in HeLa cells infected with miR-223 by Lentivirus pLL3.7 system. We observed in this model that miR-223 significantly suppressed the proliferation, growth rate, colony formation of HeLa cells in vitro, and in vivo tumorigenicity or tumor formation in nude mice. To investigate the mechanisms involved, we scanned and examined the potential and putative target molecules of miR-223 by informatics, quantitative PCR and Western blot, and found that insulin-like growth factor-1 receptor (IGF-1R) was the functional target of miR-223 inhibition of cell proliferation. Targeting IGF-1R by miR-223 was not only seen in HeLa cells, but also in leukemia and hepatoma cells. The downstream pathway, Akt/mTOR/p70S6K, to which the signal was mediated by IGF-1R, was inhibited as well. The relative luciferase activity of the reporter containing wild-type 3′UTR(3′untranslated region) of IGF-1R was significantly suppressed, but the mutant not. Silence of IGF-1R expression by vector-based short hairpin RNA resulted in the similar inhibition with miR-223. Contrarily, rescued IGF-1R expression in the cells that over-expressed miR-223, reversed the inhibition caused by miR-223 via introducing IGF-1R cDNA that didn't contain the 3′UTR. Meanwhile, we also noted that miR-223 targeted Rasa1, but the downstream molecules mediated by Rasa1 was neither targeted nor regulated. Therefore we believed that IGF-1R was the functional target for miR-223 suppression of cell proliferation and its downstream PI3K/Akt/mTOR/p70S6K pathway suppressed by miR-223 was by targeting IGF-1R

    Light hadron, Charmonium(-like) and Bottomonium(-like) states

    Full text link
    Hadron physics represents the study of strongly interacting matter in all its manifestations and the understanding of its properties and interactions. The interest on this field has been revitalized by the discovery of new light hadrons, charmonium- and bottomonium-like states. I review the most recent experimental results from different experiments.Comment: Presented at Lepton-Photon 2011, Mumbai, India; 21 pages, 18 figures; add more references; some correctio

    ruvA Mutants that resolve Holliday junctions but do not reverse replication forks

    Get PDF
    RuvAB and RuvABC complexes catalyze branch migration and resolution of Holliday junctions (HJs) respectively. In addition to their action in the last steps of homologous recombination, they process HJs made by replication fork reversal, a reaction which occurs at inactivated replication forks by the annealing of blocked leading and lagging strand ends. RuvAB was recently proposed to bind replication forks and directly catalyze their conversion into HJs. We report here the isolation and characterization of two separation-of-function ruvA mutants that resolve HJs, based on their capacity to promote conjugational recombination and recombinational repair of UV and mitomycin C lesions, but have lost the capacity to reverse forks. In vivo and in vitro evidence indicate that the ruvA mutations affect DNA binding and the stimulation of RuvB helicase activity. This work shows that RuvA's actions at forks and at HJs can be genetically separated, and that RuvA mutants compromised for fork reversal remain fully capable of homologous recombination

    Optimal control of impulsive switched systems with minimum subsystem durations

    Get PDF
    This paper presents a new computational approach for solving optimal control problems governed by impulsive switched systems. Such systems consist of multiple subsystems operating in succession, with possible instantaneous state jumps occurring when the system switches from one subsystem to another. The control variables are the subsystem durations and a set of system parameters influencing the state jumps. In contrast with most other papers on the control of impulsive switched systems, we do not require every potential subsystem to be active during the time horizon (it may be optimal to delete certain subsystems, especially when the optimal number of switches is unknown). However, any active subsystem must be active for a minimum non-negligible duration of time. This restriction leads to a disjoint feasible region for the subsystem durations. The problem of choosing the subsystem durations and the system parameters to minimize a given cost function is a non-standard optimal control problem that cannot be solved using conventional techniques. By combining a time-scaling transformation and an exact penalty method, we develop a computational algorithm for solving this problem. We then demonstrate the effectiveness of this algorithm by considering a numerical example on the optimization of shrimp harvesting operations
    corecore