22,448 research outputs found

    Antioxidant and Antitumor Activity of Indonesian Herbal Ingredients

    Full text link
    The present study was to aimed to evaluated and compare in vitro antioxidant activities of 2 Indonesian herbal ingredients (A and B), determined total phenol content., cytotoxic and apoptosis induction activities on HL-60 cells. These data were providing some useful information for people healthy dietary and the new potential application of natural antioxidant containing food materials in functional foods and also as new cancer therapeutics promising candidates. The parameters were total antioxidant activity, amount of total cytotoxic effect on the growth of human promyelocytic leukemia cells (HL-60). Statistical comparison was perform with Student's t-test at p<0.05. The correlation coefficient (r2) between the parameters tested was established by regression analysis. The scavenging effect of extracts herbal on DPPH radicals increased from 0.3-1.5 mg/ml, where is sample A 14.33% to 64.29% and sample B 9.09% to 57.53% was obtained. High content of total phenol compounds were in sample A (21.72 mg GAE/g), lower amounts were in sample B (17.53 mg GAE/g). Apoptosis of HL-60 cells from the morphological changes side (chromatin condensation). Chromatin condensation, a specific and distinct feature of apoptotic cells, was found in the majority of treated cells. The results indicated that the cell death receptor pathway was involved in the apoptosis induced by Indonesian herbal extracts

    Fermi resonance-algebraic model for molecular vibrational spectra

    Full text link
    A Fermi resonance-algebraic model is proposed for molecular vibrations, where a U(2) algebra is used for describing the vibrations of each bond, and Fermi resonances between stretching and bending modes are taken into account. The model for a bent molecule XY_2 and a molecule XY_3 is successfully applied to fit the recently observed vibrational spectrum of the water molecule and arsine (AsH_3), respectively, and results are compared with those of other models. Calculations show that algebraic approaches can be used as an effective method for describing molecular vibrations with small standard deviations

    Necessary and sufficient conditions for local creation of quantum discord

    Full text link
    We show that a local channel cannot create quantum discord (QD) for zero QD states of size d≥3d\geq3 if and only if either it is a completely decohering channel or it is a nontrivial isotropic channel. For the qubit case this propertiy is additionally characteristic to the completely decohering channel or the commutativity-preserving unital channel. In particular, the exact forms of the completely decohering channel and the commutativity-preserving unital qubit channel are proposed. Consequently, our results confirm and improve the conjecture proposed by X. Hu et al. for the case of d≥3d\geq3 and improve the result proposed by A. Streltsov et al. for the qubit case. Furthermore, it is shown that a local channel nullifies QD in any state if and only if it is a completely decohering channel. Based on our results, some protocols of quantum information processing issues associated with QD, especially for the qubit case, would be experimentally accessible.Comment: 8 page

    State-independent experimental test of quantum contextuality in an indivisible system

    Full text link
    We report the first state-independent experimental test of quantum contextuality on a single photonic qutrit (three-dimensional system), based on a recent theoretical proposal [Yu and Oh, Phys. Rev. Lett. 108, 030402 (2012)]. Our experiment spotlights quantum contextuality in its most basic form, in a way that is independent of either the state or the tensor product structure of the system

    FHL2 regulates hematopoietic stem cell functions under stress conditions.

    Get PDF
    FHL2, a member of the four and one half LIM domain protein family, is a critical transcriptional modulator. Here, we identify FHL2 as a critical regulator of hematopoietic stem cells (HSCs) that is essential for maintaining HSC self-renewal under regenerative stress. We find that Fhl2 loss has limited effects on hematopoiesis under homeostatic conditions. In contrast, Fhl2-null chimeric mice reconstituted with Fhl2-null bone marrow cells developed abnormal hematopoiesis with significantly reduced numbers of HSCs, hematopoietic progenitor cells (HPCs), red blood cells and platelets as well as hemoglobin levels. In addition, HSCs displayed a significantly reduced self-renewal capacity and were skewed toward myeloid lineage differentiation. We find that Fhl2 loss reduces both HSC quiescence and survival in response to regenerative stress, probably as a consequence of Fhl2-loss-mediated downregulation of cyclin-dependent kinase-inhibitors, including p21(Cip) and p27(Kip1). Interestingly, FHL2 is regulated under the control of a tissue-specific promoter in hematopoietic cells and it is downregulated by DNA hypermethylation in the leukemia cell line and primary leukemia cells. Furthermore, we find that downregulation of FHL2 frequently occurs in myelodysplastic syndrome and acute myeloid leukemia patients, raising a possibility that FHL2 downregulation has a role in the pathogenesis of myeloid malignancies
    • …
    corecore