64 research outputs found

    Interactions Among Murine Cytomegalovirus US22 Family Gene Products That Influence Viral Pathogenesis

    Get PDF
    Cytomegalovirus (CMV) is a complex, ubiquitous herpesvirus that is characterized by acute, chronic, and latent infections. Monocytes-macrophages are the key target cell type involved in pathogenesis, which is most effectively studied using the murine model of CMV infection. Previously three murine CMV (MCMV) genes (M139, M140, and M141) were identified to regulate viral expression in cultured macrophages and in mice. These genes are members of the US22 gene family with respect to HCMV homology. There is no function assigned to the proteins encoded by these genes. However, deletion of M139, M140, and M141 significantly curtails growth of MCMV in macrophages in vitro and in macrophage-dense target organs in vivo (Hanson et al. 1999, J.Virol. 73(7): 5970–80). Therefore, M139, M140, and/or M141 gene products likely affect tissue specific viral infectivity. The purpose of this study was to characterize these proteins (pM139, pM140, and pM141) and interaction among them. The M139, gene encodes two protein of 75 and 61 kD; M140 encodes a single protein of 56 kD, and M141 encodes a 52 kD protein. Most interestingly, when infected cell lysates were immunoprecipitated with anti-M139 antibody under non-denaturing (but not denaturing) conditions, five bands of 98-, 75-, 61-, 56-, and 52-kD proteins were co-precipitated. Likewise, anti-M140 antisera co-precipitated two bands of 56- and 52-kD, and anti-M141 antibody precipitated a less abundant 56- and an abundant 52-kD band. The co-precipitating bands were identified as products of M139, M140, and M141 genes in experiments employing mutant viruses deleted of each gene. Complex formation between the M140 and M141 proteins (PM140 and pM141) was confirmed by sequential immunoprecipitations and combined immunoprecipitation and western blotting. These two proteins also formed a complex in the absence of other viral proteins. At least one function of the pM140/pM141 complex is to stabilize expression of pM141, which is unstable in the absence of pM140. Given the complexity of viral pathogenesis and the fact that pM139, pM140, and pM141 proteins are dispensable for viral replication in tissue culture, it is possible that each single protein as well as the complex(s) they form may have a distinct function which influences tissue specific infectivity

    Growth factors mediated differentiation of mesenchymal stem cells to cardiac polymicrotissue using hanging drop and bioreactor

    Get PDF
    Heart disease is the major leading cause of death worldwide and the use of stem cells promises new ways for its treatment. The relative easy and quick acquisition of human umbilical cord matrix mesenchymal stem cells (HUMSCs) and their properties make them useful for the treatment of cardiac diseases. Therefore, the main aim of this investigation was to create cardiac polymicrotissue from HUMSCs using a combination of growth factors [sphingosine-1-phosphate (S1P) and suramin] and techniques (hanging drop and bioreactor). Using designated culture conditions of the growth factors (100 nM S1P and 500 µM suramin), cardiomyocyte differentiation medium (CDM), hanging drop, bioreactor and differentiation for 7 days, a potential specific cardiac polymicrotissue was derived from HUMSCs. The effectiveness of growth factors alone or in combination in differentiation of HUMSCs to cardiac polymicrotissue was analysed by assessing the presence of cardiac markers by immunocytochemistry. This analysis demonstrated the importance of those growth factors for the differentiation. This study for the first time demonstrated the formation of a cardiac polymicrotissue under specific culture conditions. The polymicrotissue, thus, obtained may be used in future as a 'patch' to cover the injured cardiac region and thereby useful for the treatment of heart diseases

    Screening revealed the strong cytotoxic activity of <i>Alchemilla smirnovii</i> and <i>Hypericum alpestre</i> ethanol extracts on different cancer cell lines

    Get PDF
    Compounds of plant origin are considered promising alternative approaches in the development of medicines for the prevention and treatment of cancer. The large diversity of herbal species still requires careful exploration as a source for new anticancer compounds. The goal of the study was to screen different herbal extracts traditionally used in Armenian folk medicine for their cytotoxic effect against some cancer cell lines, and to find the prospective plant species among them. The cytotoxicity of the plant ethanol extracts was evaluated with MTT test against HeLa (human cervical carcinoma) and A549 (human lung adenocarcinoma) cells. Antioxidant properties were assessed with DPPH free radical scavenging assay. Five of the tested ten herbal extracts exhibited significant growth-inhibiting activity on HeLa cells. Moreover, Alchemilla smirnovii and Hypericum alpestre extracts also showed potent cytotoxicity on human lung adenocarcinoma cells. These two plants possessed high antiradical activity as well. Their DPPH stoichiometric values were 0.4234 and 0.14437 respectively, meaning that 1 µg of plant extract brought the reduction of DPPH equal to the respective stoichiometric values in µg. Thus, A. smirnovii and H. alpestre extracts expressed themselves as potent cytotoxic and antioxidant agents and could have promising anticancer potential. Further evaluation of their in vivo anticancer properties has much interest

    The HERA-B Ring Imaging Cherenkov Counter

    Full text link
    The HERA-B RICH uses a radiation path length of 2.8 m in C_4F_10 gas and a large 24 square meters spherical mirror for imaging Cherenkov rings. The photon detector consists of 2240 Hamamatsu multi-anode photomultipliers with about 27000 channels. A 2:1 reducing two-lens telescope in front of each PMT increases the sensitive area at the expense of increased pixel size, resulting in a contribution to the resolution which roughly matches that of dispersion. The counter was completed in January of 1999, and its performance has been steady and reliable over the years it has been in operation. The design performance of the RICH was fully reached: the average number of detected photons in the RICH for a beta=1 particle was found to be 33 with a single hit resolution of 0.7 mrad and 1 mrad in the fine and coarse granularity regions, respectively.Comment: 29 pages, 23 figure

    Formation of cardiac fibers in Matrigel matrix

    Full text link
    The Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform March 202

    Effects of N-cadherin overexpression on the adhesion properties of embryonic stem cells

    No full text
    Constitutive overexpression of N-cadherin in mouse embryonic stem cells led to marked changes in the phenotype and adhesion properties of these cells. The changes included the formation of smaller embryonic bodies, elevated mRNA and total protein levels of N-cadherin, and increased amounts of p120 catenin and connexin-43. N-cadherin cells exhibited decreased attachment to non-cell surfaces, while their adhesiveness to each other and to rat neonatal cardiomyocytes was significantly elevated. The findings suggest that N-cadherin overexpression can facilitate electromechanical integration of stem cells into excitable tissues with endogenously high levels of N-cadherin, such as the heart and brain
    corecore