335 research outputs found

    Phosphorylation Of Cytoskeletal Proteins By Protein Kinase C

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    Protein kinase C is the Ca{dollar}\sp{lcub}2+{rcub}{dollar}/phospholipid-dependent enzyme that serves as the receptor for, and is directly activated by, the tumour-promoting phorbol esters. To examine the involvement of protein kinase C in the regulation of the organization or function of the actin-containing microfilaments, the activity of the enzyme towards two distinct groups of proteins that are thought to be involved in microfilament regulation has been investigated. For these studies, protein kinase C was partially purified from bovine brain or was more extensively purified from rat brain. Two proteins that are localized in certain areas of microfilament-membrane attachment (focal contacts), vinculin and talin, were identified as in vitro substrates for protein kinase C. Purified protein kinase C also phosphorylated chicken gizzard myosin light chain kinase and different forms of caldesmon, proteins that are involved in the regulation of contractile events. Chicken gizzard caldesmon and chicken liver caldesmon{dollar}\sb{lcub}72{rcub}{dollar} as well as two forms of bovine live caldesmon (caldesmon{dollar}\sb{lcub}150{rcub}{dollar} and caldesmon{dollar}\sb{lcub}77{rcub}{dollar}) were all in vitro substrates for protein kinase C. The sites of phosphorylation of the substrate proteins were examined by phosphopeptide mapping and phosphoamino acid analysis. Phosphorylation of chicken gizzard caldesmon by protein kinase C partially abolished its inhibitory activity towards the actin-activated ATPase of skeletal muscle myosin and diminished associations between caldesmon and actin.;Treatment of intact human platelets with 12-O-tetradecanoyl-phorbol-13-acetate (TPA), a tumour-promoter that activates protein kinase C in living cells, stimulated phosphorylation of talin and caldesmon{dollar}\sb{lcub}77{rcub}{dollar}. The phosphate content of talin was elevated by 44%, but the apparent stoichiometry of phosphorylation was low. In contrast, the phosphate content of caldesmon{dollar}\sb{lcub}77{rcub}{dollar} increased approximately 4-fold. Moreover, the phosphopeptides that appeared in response to TPA treatment had the same migration pattern as the two major phosphopeptides of bovine liver caldesmon{dollar}\sb{lcub}77{rcub}{dollar} phosphorylated in vitro.;The results of this study imply that protein kinase C, by phosphorylating focal contact proteins or proteins involved in the control of contractile events, may have a role in microfilament regulation

    The simulation of an automatic punch press line

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    Objectives of the development of the simulation are: a. To develop a model for the operation of an existing automatic punch press line, b. To write a program for the LGP-30 Digital Computer, c. To analyze the program and the model

    Molecular pathways: Emergence of protein kinase CK2 (CSNK2) as a potential target to inhibit survival and DNA damage response and repair pathways in cancer cells

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    ©2016 AACR. Protein kinase CK2 (designated CSNK2) is a constitutively active protein kinase with a vast repertoire of putative substrates that has been implicated in several human cancers, including cancer of the breast, lung, colon, and prostate, as well as hematologic malignancies. On the basis of these observations, CSNK2 has emerged as a candidate for targeted therapy, with two CSNK2 inhibitors in ongoing clinical trials. CX-4945 is a bioavailable small-molecule ATP-competitive inhibitor targeting its active site, and CIGB-300 is a cell-permeable cyclic peptide that prevents phosphorylation of the E7 protein of HPV16 by CSNK2. In preclinical models, either of these inhibitors exhibit antitumor efficacy. Furthermore, in combinations with chemotherapeutics such as cisplatin or gemcitabine, either CX-4945 or CIGB-300 promote synergistic induction of apoptosis. While CSNK2 is a regulatory participant in many processes related to cancer, its potential to modulate caspase action may be particularly pertinent to its emergence as a therapeutic target. Because the substrate recognition motifs for CSNK2 and caspases are remarkably similar, CSNK2 can block the cleavage of many caspase substrates through the phosphorylation of sites adjacent to cleavage sites. Phosphoproteomic strategies have also revealed previously underappreciated roles for CSNK2 in the phosphorylation of several key constituents of DNA damage and DNA repair pathways. Going forward, applications of proteomic strategies to interrogate responses to CSNK2 inhibitors are expected to reveal signatures for CSNK2 inhibition and molecular insights to guide new strategies to interfere with its potential to inhibit caspase action or enhance the susceptibility of cancer cells to DNA damage

    Protein kinase CK2: Intricate relationships within regulatory cellular networks

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    © 2017 by the authors. Licensee MDPI, Basel, Switzerland. Protein kinase CK2 is a small family of protein kinases that has been implicated in an expanding array of biological processes. While it is widely accepted that CK2 is a regulatory participant in a multitude of fundamental cellular processes, CK2 is often considered to be a constitutively active enzyme which raises questions about how it can be a regulatory participant in intricately controlled cellular processes. To resolve this apparent paradox, we have performed a systematic analysis of the published literature using text mining as well as mining of proteomic databases together with computational assembly of networks that involve CK2. These analyses reinforce the notion that CK2 is involved in a broad variety of biological processes and also reveal an extensive interplay between CK2 phosphorylation and other post-translational modifications. The interplay between CK2 and other post-translational modifications suggests that CK2 does have intricate roles in orchestrating cellular events. In this respect, phosphorylation of specific substrates by CK2 could be regulated by other post-translational modifications and CK2 could also have roles in modulating other post-translational modifications. Collectively, these observations suggest that the actions of CK2 are precisely coordinated with other constituents of regulatory cellular networks

    Can process mining automatically describe care pathways of patients with long-term conditions in UK primary care? A study protocol

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    Introduction In the UK, primary care is seen as the optimal context for delivering care to an ageing population with a growing number of long-term conditions. However, if it is to meet these demands effectively and efficiently, a more precise understanding of existing care processes is required to ensure their configuration is based on robust evidence. This need to understand and optimise organisational performance is not unique to healthcare, and in industries such as telecommunications or finance, a methodology known as ‘process mining’ has become an established and successful method to identify how an organisation can best deploy resources to meet the needs of its clients and customers. Here and for the first time in the UK, we will apply it to primary care settings to gain a greater understanding of how patients with two of the most common chronic conditions are managed. Methods and analysis The study will be conducted in three phases; first, we will apply process mining algorithms to the data held on the clinical management system of four practices of varying characteristics in the West Midlands to determine how each interacts with patients with hypertension or type 2 diabetes. Second, we will use traditional process mapping exercises at each practice to manually produce maps of care processes for the selected condition. Third, with the aid of staff and patients at each practice, we will compare and contrast the process models produced by process mining with the process maps produced via manual techniques, review differences and similarities between them and the relative importance of each. The first pilot study will be on hypertension and the second for patients diagnosed with type 2 diabetes

    Patients' perceptions and experiences of the prevention of hospital-acquired thrombosis : a qualitative study

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    Objective To examine patients' understanding of hospital-associated thrombosis, and their experiences of thromboprophylaxis. Design Qualitative study using semi-structured interviews with 31 patients requiring venous thromboembolism (VTE) prophylaxis following a recent hospital admission. Interviews were audio-recorded, transcribed verbatim and analysed thematically using framework analysis. Setting 4 hospitals in Birmingham and Oxford. Results All the participants received thromboprophylaxis following surgical procedures. Participants were aware of a risk of blood clots; however, they lacked a good understanding of VTE and its components. Experiences of VTE prophylaxis were characterised with good adherence to heparin injections and poor adherence to elastic compression stockings, largely due to perceived lack of clarity in guidance from health professionals. Participants had limited knowledge of the signs and symptoms of VTE and would value improved education on VTE. Conclusions Findings suggest that patient education is often inadequate and impacts negatively on patients' involvement in VTE prevention. An enhanced patient education programme incorporating a consistent message on the appropriate use of elastic compression stockings and description of VTE symptoms is likely to optimise the effectiveness of the prevention of hospital-associated thrombosis. Physicians may use the results of this study to improve individual patient education

    Development of an unbiased statistical method for the analysis of unigenic evolution

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    BACKGROUND: Unigenic evolution is a powerful genetic strategy involving random mutagenesis of a single gene product to delineate functionally important domains of a protein. This method involves selection of variants of the protein which retain function, followed by statistical analysis comparing expected and observed mutation frequencies of each residue. Resultant mutability indices for each residue are averaged across a specified window of codons to identify hypomutable regions of the protein. As originally described, the effect of changes to the length of this averaging window was not fully eludicated. In addition, it was unclear when sufficient functional variants had been examined to conclude that residues conserved in all variants have important functional roles. RESULTS: We demonstrate that the length of averaging window dramatically affects identification of individual hypomutable regions and delineation of region boundaries. Accordingly, we devised a region-independent chi-square analysis that eliminates loss of information incurred during window averaging and removes the arbitrary assignment of window length. We also present a method to estimate the probability that conserved residues have not been mutated simply by chance. In addition, we describe an improved estimation of the expected mutation frequency. CONCLUSION: Overall, these methods significantly extend the analysis of unigenic evolution data over existing methods to allow comprehensive, unbiased identification of domains and possibly even individual residues that are essential for protein function

    A review and comparative study of release coatings for optimised abhesion in resin transfer moulding applications

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    In this study, a number of abhesion promoting coatings were considered in terms of their physicochemical and release properties. The techniques used to further this study include; FEGSEM, AFM, profilometry, AFM, XPS, AES, SSIMS, FTIR and contact angle analysis for coating physical and chemical characterisation along with PF-AFM and other adhesion and mechanical tests to determine surface release properties. These coatings were applied to metal substrates and were based upon silicone, fluoropolymer or metal-PTFE composite chemistry, all being potentially useful as release films for resin transfer moulding (RTM) applications. The semi-permanent Frekote B15/710 NC mould release coating system, which is based on PDMS, proved extremely effective in terms of release against a cured epoxide applied under pressure. Although fluoroalkylsilane coatings offer a number of technological advantages for release applications they generally produce very thin coatings which conform any existing surface topography and adhesion through mechanical interlocking occurs. The commercial PTFE-based coatings were found to provide poor release properties due to the presence of surface microcracks which allowed epoxide penetration when cured under elevated pressure and temperature. Electroless Ni/PTFE composite coatings comprise hard nickel-phosphorus matrix containing a very fine dispersion of PTFE particles. The matrix proved sufficiently robust for industrial applications and the low friction and surface energy provided by the embedded PTFE combined with macroscopic scale surface roughness provided efficient mould release

    An Inverted Mass Hierarchy for Hot Dark Matter and the Solar Neutrino Problem.

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    The cosmological model in which 20% of the dark matter is shared by two nearly equal mass neutrinos fits the structure of the universe on all scales. This has been motivated a νμ\nu_\mu-ντ\nu_{\tau} oscillation explanation of the deficit of atmospheric muon neutrinos. If the observed ratio of atmospheric nuμnu_\mu to νe\nu_e has an alternative explanation, the cosmological model can be retained if the deficit of solar neutrinos is explained by νe\nu_e-ντ\nu_{\tau} oscillation. In this case an inverted mass hierarchy is required with mνμ≪mνe≃mντ≈2.4m_{\nu_{\mu}}\ll m_{\nu_e} \simeq m_{\nu_\tau}\approx 2.4 eV. We show that if there exists an Le−LτL_e- L_{\tau} symmetry in nature, both the near mass degeneracy of \nue\ and \nut\ as well as the consistency of the above values for neutrino masses with the negative results for neutrinoless double beta decay search experiments are easily understood. We show that this symmetry implemented in the context of a high-scale left-right symmetric theory with the see-saw mechanism can lead to a simple theoretical understanding of the desired form of the mass matrix.Comment: Tex file; no figures; 10 page
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