234 research outputs found

    The calpastatin-derived calpain inhibitor CP1B reduces mRNA expression of matrix metalloproteinase-2 and-9 and invasion by leukemic THP-1 cells

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    The ubiquitous proteases Ό- and m-calpain are Ca2+-dependent cysteine endopeptidases. Besides involvement in a variety of physio(patho)logical processes, recent studies suggest a pivotal role of calpains in differentiation of hematopoietic cells and tumor cell invasion. However, the precise actions of calpains and their endogenous inhibitor, calpastatin, in these processes are only partially understood. Here we have studied the role of the calpain/calpastatin system in the invasion of leukemic cells under basal and differentiationstimulating conditions. To further differentiate the human leukaemic cell line THP-1 (monocytic), the cells were treated for 24 hours with the differentiationstimulating reagents phorbol 12-myristate 13-acetate (PMA) and dimethyl sulfoxide (DMSO). Macrophage and granulocytelike differentiation was confirmed by induction of vimentin expression as well as by microscopic and fluorescence assisted cytometric analysis. Extracellular matrix (ECM) invasion of both the basal and differentiation stimulated cells in a Matrigel assay was inhibited by preincubation of the cells with the specific calpain inhibitor CP1B for 24 hours. Inhibition of invasiveness correlated with decreased mRNA expression and secretion of the matrix metalloproteinases MMP-2 and MMP-9. In contrast, addition of CP1B only during the invasion process did neither influence transmigration nor MMP release. This is the first report showing that the calpain/calpastatin system mediates MMPmRNA expression of the leukemic THP-1 cells and as a consequence their invasiveness

    mHealth optimisation for education and physical activity in Type 1 diabetes: MEDPAT1.

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    Aims: To develop and evaluate usability of prototype personalised prediction algorithms for people with Type 1 diabetes to optimise blood glucose control associated with physical activity using smart phone technology. To explore the potential to build a knowledge repository founded on case-based reasoning and linkage with an online structured education programme that will increase confidence and levels of participation in physical activity

    The Impact of Cell Phone Texting During Aerobic Exercise on Measures of Cognition

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    International Journal of Exercise Science 12(5): 646-656, 2019. This study assessed the effect of cell phone texting during a 30-minute bout of cycle ergometer exercise on measures of cognition (i.e., reaction time and accuracy). Twenty-eight college students participated in two conditions (cell phone and no cell phone). Reaction time and accuracy were assessed pre- and post-exercise with the use of the Stroop test. Reaction time was significantly worse (p \u3c 0.001) in the cell phone condition from pre- (1003.75 ± 178.04 ms) to post-exercise (1124.46 ± 238.55 ms). Reaction time was significantly better (p \u3c 0.001) in the no cell phone condition from pre- (1107.71 ± 229.54 ms) to post-exercise (953.86 ± 177.42 ms). Accuracy was significantly worse (p = 0.01) in the cell phone condition from pre- (97.61 ± 2.32) to post-exercise (94.04 ± 7.88). Accuracy was significantly better (p \u3c 0.001) in the no cell phone condition from pre- (94.82 ± 4.42) to post-exercise (97.39 ± 2.42). In conclusion, using your cell phone for texting can interfere with the cognitive benefits associated with reaction time and accuracy that are developed from participating in aerobic exercise

    m-Calpain is required for preimplantation embryonic development in mice

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    BACKGROUND: Ό-calpain and m-calpain are ubiquitously expressed proteases implicated in cellular migration, cell cycle progression, degenerative processes and cell death. These heterodimeric enzymes are composed of distinct catalytic subunits, encoded by Capn1 (Ό-calpain) or Capn2 (m-calpain), and a common regulatory subunit encoded by Capn4. Disruption of the mouse Capn4 gene abolished both Ό-calpain and m-calpain activity, and resulted in embryonic lethality, thereby suggesting essential roles for one or both of these enzymes during mammalian embryogenesis. Disruption of the Capn1 gene produced viable, fertile mice implying that either m-calpain could compensate for the loss of Ό-calpain, or that the loss of m-calpain was responsible for death of Capn4(-/- )mice. RESULTS: To distinguish between the alternatives described above, we deleted an essential coding region in the mouse Capn2 gene in embryonic stems cells and transmitted this mutant allele through the mouse germline. Breeding of heterozygous animals failed to produce homozygous mutant live offspring or implanted embryos. A nested PCR genotyping protocol was established, and homozygous preimplantation mutant embryos were detected at the morula but not at the blastocyts stage. CONCLUSION: We conclude that homozygous disruption of the Capn2 gene results in pre-implantation embryonic lethality between the morula and blastocyst stage. This establishes that Ό-calpain and m-calpain have distinct functions, and that m-calpain is vital for development of the preimplantation murine embryo

    Competitive nationalism:state, class, and the forms of capital in devolved Scotland

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    Devolved government in Scotland actively reconstitutes the unequal conditions of social class reproduction. Recognition of state-led class reconstitution draws upon the social theory of Bourdieu. Our analysis of social class in devolved Scotland revisits theories that examine the state as a `power container'. A range of state-enabling powers regulate the legal, economic, social, and cultural containers of class relations as specific forms of what Bourdieu called economic, social, and cultural `capital'. The preconditions of class reproduction are structured in direct ways by the Scottish state as a wealth container but also, more indirectly, as a cultural container and a social container. Competitive nationalism in the devolved Scottish state enacts neoliberal policies as a class- specific worldview but, at the same time, discursively frames society as a panclass national fraternity in terms of distinctive Scottish values of welfare nationalism. Nationalism is able to express this ambiguity in symbolic ways in which the partisan language of social class cannot

    Calpain Cleavage Prediction Using Multiple Kernel Learning

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    Calpain, an intracellular -dependent cysteine protease, is known to play a role in a wide range of metabolic pathways through limited proteolysis of its substrates. However, only a limited number of these substrates are currently known, with the exact mechanism of substrate recognition and cleavage by calpain still largely unknown. While previous research has successfully applied standard machine-learning algorithms to accurately predict substrate cleavage by other similar types of proteases, their approach does not extend well to calpain, possibly due to its particular mode of proteolytic action and limited amount of experimental data. Through the use of Multiple Kernel Learning, a recent extension to the classic Support Vector Machine framework, we were able to train complex models based on rich, heterogeneous feature sets, leading to significantly improved prediction quality (6% over highest AUC score produced by state-of-the-art methods). In addition to producing a stronger machine-learning model for the prediction of calpain cleavage, we were able to highlight the importance and role of each feature of substrate sequences in defining specificity: primary sequence, secondary structure and solvent accessibility. Most notably, we showed there existed significant specificity differences across calpain sub-types, despite previous assumption to the contrary. Prediction accuracy was further successfully validated using, as an unbiased test set, mutated sequences of calpastatin (endogenous inhibitor of calpain) modified to no longer block calpain's proteolytic action. An online implementation of our prediction tool is available at http://calpain.org
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