Preparation of the myristoylated and nonmyristoylated form of recombinant recoverin in E. coli cells and comparison of their functional activity]

Numerous data strongly suggest the involvement of cytokines and the matrix metalloproteinase collagenase (MMP-1) in the pathogenesis of periodontitis. Recently, we have demonstrated that, upon culturing under the influence of IL-1 alpha + EGF, a large amount of inactive procollagenase (MMP-1) is stored in the extracellular matrix of periosteal tissue. We now show that this endogenous reservoir of proenzyme can be operative after activation with plasmin and is able to induce a rapid and almost complete breakdown of the collagenous extracellular matrix. The level of collagen degradation following activation showed a strong correlation with the amount of proenzyme that was incorporated in the tissue. The highest level of degradation (70% of the total amount of collagenous proteins) was found with the IL-1 alpha + EGF-treated explants, followed by those treated with IL-1 alpha alone (35%). Explants cultured with EGF or in the absence of cytokines, containing only small amounts of procollagenase, showed little collagen breakdown following plasmin activation (7%). Inhibition of metalloproteinases by EDTA, or blockage of plasmin by PMSF, prevented the degradation in all explants irrespective of the amount of proenzyme present in the tissue. Our findings demonstrate that endogenous proenzyme stored in a native connective tissue matrix can be activated at a later time interval which results in a massive breakdown of the tissue. This study shows a possible pathway of collagenase-induced breakdown without recent de novo synthesis of the enzyme. Such a sequence may be operative in chronic inflammatory diseases, such as periodontitis, where production of procollagenase under the influence of cytokines spans a longer time period, whereas breakdown is often characterized by a cyclic behaviour.     

Performance monitoring of the EC - 1030 system by a microprocessor - based monitor

This paper presents a M6800 microprocessor based hardware monitor for measuring certain selected parameters of the EC-1030 computer system. The motivation for this work was to get an insight into the operation of the system under the present work load and use these results towards improvement and design studies. The three main classes of quantitative indices of computer system performance/productivity, responsiveness and use have been measured using hardware and software tools. This paper describes the hardware monitor design and discusses the measurements made.     

Calculation of the interaction of supersonic counter flows

The maximum stable difference scheme of second order accuracy is described for axisymmetrical flows with shock waves and the results are given of a calculation of the interaction between an external supersonic flow and a counter supersonic jet issuing from a cylindrical channel.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol.27, No.3, pp. 430–437, September, 1974.     

Assessing coal concentrate by means of an Audibert-Arnu dilatometer

The relation between the plastic-layer thickness (defined by Sapozhnikov and Bazilevich) and the expansion index (defined by Audibert and Arnu) is established. It is found that Audibert-Arnu dilatometry more precisely reflects coal quality. The change in quality of concentrates from individual enrichment enterprises is assessed for the period 2006–2008.     

Simulation of magnetic reconnection in 3D geometry

The mathematical model of magnetic reconnection in the vicinity of critical points is discussed in the frame of 3D magneto-hydrodynamics. A mixed problem for an initial magnetic configuration without external currents was formulated and solved numerically. The evolution of a magnetic field in the vicinity of the null point and null line for the case of the forced magnetic reconnection mode is considered. Results of computational experiments concerning the formation of complex self-organizing nonlinear structures are presented.