13,162 research outputs found
Meloxicam decreases the migration and invasion of CF41.Mg canine mammary carcinoma cells
Indexación: Web of Science; Scopus.Cyclooxygenase (COX)-2 expression is positively correlated with malignant features in canine mammary carcinomas. Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit COX activity and may therefore possess anticancer effects. Meloxicam is an NSAID that is widely used in human and veterinary medicine. High concentrations of meloxicam have been reported to be antitumorigenic in vitro; however, the effect of meloxicam at concentrations that are equivalent to those that can be obtained in vivo remains unknown. In the current study, the in vitro effects of low-dose meloxicam (0.25 μg/ml) on CF41.Mg canine mammary carcinoma cells were evaluated. The effects on cell proliferation, apoptosis, cell migration and invasion, in addition to the expression of different molecules associated with tumor invasiveness were analyzed. No effect on cell viability and apoptosis were observed. However, cell migration and invasion were significantly reduced following treatment with meloxicam. MMP-2 expression and activity were similarly reduced, explaining the impaired cell invasion. In addition, β-catenin expression was downregulated, while its phosphorylation increased. These results indicate that 0.25 μg/ml meloxicam reduces cell migration and invasion, in part through modulating MMP-2 and β-catenin expression. Additional studies are required to elucidate the mechanism associated with the anti-invasive effect of meloxicam on CF41.Mg cells. The results of the present study suggest that meloxicam has a potential adjunctive therapeutic application, which could be useful in controlling the invasion and metastasis of canine mammary carcinomas.https://www.spandidos-publications.com/10.3892/ol.2017.640
Poiseuille flow in a nanochannel – use of different thermostats
Poiseuille flow of a liquid in a nano-channel is simulated by molecular dynamics by embedding the fluid particles in a uniform force field. The channel is periodic in y and z directions and along x direction it is bounded by atomic walls. The imposition of the body force generates heat in the system leading to shear heating and a non-uniform temperature rise across the channel. In this nonequilibrium system, one can attempt to control temperature in different ways: velocity rescaling, thermostats or wall-fluid coupling. We evaluate and compare different methods critically by analyzing the fluctuations and time averaged quantities from various simulations. When particles will be inserted into the flow, it is expected that the dynamics will depend on the thermostat chosen. First observations show little influence of the thermostats on single tracer particles – this needs further study
A Multiwavelength Investigation of the Relationship Between 2CG135+1 and LSI+61o 303
We present the results of a multiwavelength monitoring campaign targeting the
gamma-ray source 2CG 135+1 in an attempt to confirm the association of this
object with the radio/Be/X-ray binary system LSI +61o 303. The campaign
included simultaneous radio, optical, infrared, and hard x-ray/gamma-ray
observations carried out with a variety of instruments, covering (not
continously) almost three binary cycles of LSI +61o 303 during the period
April-July 1994. Three separate OSSE observations of the gamma-ray source were
carried out, covering different phases of the radio lightcurve. Hard
X-ray/gamma-ray emission was detected from the direction of 2CG 135+1 during
the first of these OSSE observations. The signal to noise ratio of the OSSE
observations was insufficient to establish a spectral or intensity correlation
of the high-energy emission with simultaneous radio, optical and infrared
emission of LSI +61o 303. We briefly discuss the theoretical implications of
our observations.Comment: 17 pages, 9 figures, 6 tables to be published in Astrophysical
Journal, 10 April 199
Statistics of Core Lifetimes in Numerical Simulations of Turbulent, Magnetically Supercritical Molecular Clouds
We present measurements of the mean dense core lifetimes in numerical
simulations of magnetically supercritical, turbulent, isothermal molecular
clouds, in order to compare with observational determinations. "Prestellar"
lifetimes (given as a function of the mean density within the cores, which in
turn is determined by the density threshold n_thr used to define them) are
consistent with observationally reported values, ranging from a few to several
free-fall times. We also present estimates of the fraction of cores in the
"prestellar", "stellar'', and "failed" (those cores that redisperse back into
the environment) stages as a function of n_thr. The number ratios are measured
indirectly in the simulations due to their resolution limitations. Our approach
contains one free parameter, the lifetime of a protostellar object t_yso (Class
0 + Class I stages), which is outside the realm of the simulations. Assuming a
value t_yso = 0.46 Myr, we obtain number ratios of starless to stellar cores
ranging from 4-5 at n_thr = 1.5 x 10^4 cm^-3 to 1 at n_thr = 1.2 x 10^5 cm^-3,
again in good agreement with observational determinations. We also find that
the mass in the failed cores is comparable to that in stellar cores at n_thr =
1.5 x 10^4 cm^-3, but becomes negligible at n_thr = 1.2 x 10^5 cm^-3, in
agreement with recent observational suggestions that at the latter densities
the cores are in general gravitationally dominated. We conclude by noting that
the timescale for core contraction and collapse is virtually the same in the
subcritical, ambipolar diffusion-mediated model of star formation, in the model
of star formation in turbulent supercritical clouds, and in a model
intermediate between the previous two, for currently accepted values of the
clouds' magnetic criticality.Comment: 25 pages, 8 figures, ApJ accepted. Fig.1 animation is at
http://www.astrosmo.unam.mx/~e.vazquez/turbulence/movies/Galvan_etal07/Galvan_etal07.htm
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