Hepatocyte growth factor (HGF) induced scattering and cell migration of human gastric adenocarcinoma MKN-74. HGF also significantly promoted the growth of MKN-74 cells in a dose-dependent manner, although HGF is reported to be antiproliferative for the growth of tumor cell lines. This result indicates that HGF stimulates cell proliferation of not only normal epithelial cells but also certain ca...

The BL Lac object Mkn 501 was observed with the BeppoSAX satellite at three epochs in April-May 1998, simultaneously with the Whipple and HEGRA Cherenkov telescopes. The X-ray spectrum is well detected up to 70 keV and it exhibits, at all epochs, a continuous curvature, which is here modeled with three power-laws of increasingly steeper index at larger energies. In the νF ν representation the s...

We present photoionization modelling of the Extended Narrow Line Region (ENLR) in Mkn 79 based on long-slit spectra presented in our previous paper (Nazarova et al. 1996). The ENLR has been modelled with two gas components: a system of high density clouds embedded in a low density gas envelope. The ENLR line fluxes have been calculated allowing for attenuation of the nuclear ionizing continuum ...

Observational and theoretical results indicate that low-redshift BL Lacertae objects are the most likely extragalactic sources to be detectable at TeV energies. In this paper we present the results of observations of 4 BL Lacertae objects (PKS0521 365, EXO0423.4 0840, PKS2005 489 and PKS2316 423) made between 1993 and 1996 with the CANGAROO 3.8m imaging Cerenkov telescope. During the period of ...

We present the expected variability features in the context of the Synchro-Self-Compton (SSC) model of emission from Active Galactic Nuclei (AGNs). We show that the homogeneous SSC model can describe well the observed mul-tiwavelength spectrum and variability of objects such as Mkn 421 and Mkn 501; however in order to explain the very fast flaring timescales occasionally observed from these obj...

This study examined whether human gastric carcinoma cells produced EGF for self-stimulation, using TMK-1 and MKN-28 cells which express mRNA for EGF and EGF receptor. EGF protein production was confirmed by ELISA and flow cytometric analysis. The lysates of these cells replaced EGF-induced biological activity to EGF receptor bearing KB cells but the culture supernatants did not. Furthermore, EG...

Interleukin-1beta is up-regulated in the presence of Helicobacter pylori infection. H. pylori infection was associated with E-cadherin methylation. In this study, we examined if IL-1beta could induce promoter methylation of E-cadherin in human gastric cancer cell lines TMK-1, MKN-74 and MKN-7. Cells were treated with IL-1beta (0.025, 0.1, 0.25, 1.0, 2.5 ng/mL) for 6, 12 and 24h. Methylation sta...

The ionized disc reflection model of Ross & Fabian is applied to a sample of five Seyfert 1 galaxies observed by BeppoSAX. Good fits were obtained for all the objects in the sample. NGC 4051 and Mkn 335 (usually classified as NLSy 1s) show evidence of a highly ionized accretion disc (ξ ∼ 350 erg cm s and ξ ∼ 800 erg cm s). While NGC 3783 seems to be a “pure Sy 1” characterized by a highly ioniz...

The intrinsic BL Lac spectra above few hundreds GeV can be very different from the observed ones due to the absorption effects by the diffuse Extragalactic Background Light (EBL), at present poorly known. With the recent results, there are now 4 sources with good spectral information: Mkn 421 (z=0.031), Mkn 501 (z=0.034), 1ES 1426+428 (z=0.129) and 1ES 1959+650 (z=0.047). Making simple assumpti...