Search results for "DAS"

Inhibition of proteasome function induces programmed cell death in proliferating endothelial cells.

2000

Proteolysis mediated by the ubiquitin-proteasome system has been implicated in the regulation of programmed cell death. Here we investigated the differential effects of proteasomal inhibitors on the viability of proliferating and quiescent primary endothelial cells in vitro and in vivo. Subconfluent, proliferating cells underwent carbobenzoxy-L-isoleucyl-gamma-t-butyl-L-glutamyl-L-alanyl-L-leucinal (PSI) -induced apoptosis at low concentrations (EC(50)=24 nM), whereas at least 340-fold higher concentrations of PSI were necessary to obtain the same effect in confluent, contact-inhibited cells. PSI-mediated cell death could be blocked by a caspase-3 inhibitor (Ac-DEVD-H), but not by a caspase…

Phytochemical indicaxanthin suppresses 7-ketocholesterol-induced THP-1 cell apoptosis by preventing cytosolic Ca(2+) increase and oxidative stress.

2012

7-Ketocholesterol (7-KC)-induced apoptosis of macrophages is considered a key event in the development of human atheromas. In the present study, the effect of indicaxanthin (Ind), a bioactive pigment from cactus pear fruit, on 7-KC-induced apoptosis of human monocyte/macrophage THP-1 cells was investigated. A pathophysiological condition was simulated by using amounts of 7-KC that can be reached in human atheromatous plaque. Ind was assayed within a micromolar concentration range, consistent with its plasma level after dietary supplementation with cactus pear fruit. Pro-apoptotic effects of 7-KC were assessed by cell cycle arrest, exposure of phosphatidylserine at the plasma membrane, varia…

Effect of flupirtine on cell death of human umbilical vein endothelial cells induced by reactive oxygen species.

1999

Abstract Flupirtine (KATADOLON®), known as a nonopiate centrally acting analgesic drug, was tested as to its potential to prevent apoptosis of human endothelial cells induced by reactive oxygen species (ROS). It was found that Flupirtine displayed no effect on viability and cell proliferation of human umbilical vein endothelial cells (HUVEC) up to a concentration of 10 μg/mL. Apoptosis, induced by ROS and generated by hypoxanthine/xanthine oxidase (EC 1.1.3.22) (HX/XOD) or t-butyl hydroperoxide, was reduced after preincubation with Flupirtine for 3 hr by 35% and 41%, respectively. The maximal cytoprotective effect against apoptosis was observed at a drug concentration of 1 to 3 μg/mL. Flow …

Biznesa procesu modelēšana, izmantojot metamodelēšanas paņēmienus : kopsavilkums

2007

Darba tēma ir saistīta ar biznesa procesu vadības sistēmu izstrādi. Šajā darbā biznesa procesu modelēšanas problēmas ir risinātas, izmantojot metamodelēšanas paņēmienus. Metamodelēšana ļauj dažādus biznesa modelēšanas aspektus aplūkot vienotā un vispārīgā formā, tai pat laikā nezaudējot precīzu jēdzienu nozīmi. Galvenie pētījumu rezultāti ir sekojoši: Izstrādāts vienots biznesa procesu un to apkārtnes metamodelis, kas parāda biznesa modelēšanas jēdzienus un to saistību. Izstrādāta biznesa modeļu jēdzienu kartēšanas metode jēdzienu kartēšanai no viena domēna uz vairākām modelēšanas valodām. Izstrādāta precīza Unified Modeling Language Aktivitāšu diagrammas (UML AD) izpildes semantika, izmant…

Identification and characterization of new prolylendopeptidases (PEPs) from Actinomycetes

2011

Immune depression induced by acanthocephalan parasites in their intermediate crustacean host: consequences for the risk of super-infection and links …

2009

9 pages; International audience; Parasite survival in hosts mainly depends on the capacity to circumvent the host immune response. Acanthocephalan infections in gammarids are linked with decreased activity of the prophenoloxidase (ProPO) system, suggesting an active immunosuppression process. Nevertheless, experimental evidence for this hypothesis is lacking: whether these parasites affect several immune pathways is unknown and the consequences of such immune change have not been investigated. In particular, the consequences for other pathogens are not known; neither are the links with other parasite-induced manipulations of the host. Firstly, using experimental infections of Pomphorhynchus…

Seprase-DPPIV Association and Prolyl Peptidase and Gelatinase Activities of the Protease Complex

2005

The N-glycan processing in HT-29 cells is a function of their state of enterocytic differentiation. Evidence for an atypical traffic associated with …

1991

International audience; When the human colon cancer cells HT-29 undergo enterocytic differentiation, they correctly process their N-glycans, whereas their undifferentiated counterpart are unable to process Man9-8-GlcNAc2 species, the natural substrate of alpha-mannosidase I. As this enzyme is fully active in both HT-29 cell populations, we hypothesize that N-glycoproteins are unable to reach the cis Golgi, the site where alpha-mannosidase I has been localized. We have demonstrated this point by using 1-deoxymannojirimycin, leupeptin, and monensin. In the presence of 1-deoxymannojirimycin, a specific inhibitor of alpha-mannosidase I, differentiated HT-29 cells, as expected, accumulate Man9-8…

Secretion of haemolysins and proteases by Aeromonas hydrophila EO63: separation and characterization of the serine protease (caseinase) and the metal…

2004

C . E S T E V E A N D T . H . B I R K B E C K . 2004. Aims: To determine the haemolysins and proteases excreted by the virulent strain EO63 of Aeromonas hydrophila grown in complex media and to then fractionate and characterize them, in particular those with elastolytic activity. Methods and Results: The amount of haemolytic and proteolytic activity in EO63 culture supernatants was dependent on the culture media used. In all media, haemolysins appeared during the phase of active growth and haemolytic activity decreased quickly thereafter, as previously described for aerolysin. In contrast, proteases were mainly released during the stationary phase. Serine protease activity in EO63 culture s…

Inhibition of glycosaminoglycan modification of perlecan domain I by site-directed mutagenesis changes protease sensitivity and laminin-1 binding act…

1998

AbstractGlycosaminoglycan attachment to perlecan domain I (173 residues) was completely prevented by site-directed mutagenesis of Ser-65, Ser-71 and Ser-76 as shown by recombinant production in mammalian cells. This did not interfere with the proper folding of the domain's SEA module but enhanced its sensitivity to neutral proteases. Lack of substitution also abolished binding to the two major heparin binding sites of laminin-1.