On the Z_p-ranks of tamely ramified Iwasawa modules

For a prime number p, we denote by K the cyclotomic Z_p-extension of a number field k. For a finite set S of prime numbers, we consider the S-ramified Iwasawa module which is the Galois group of the maximal abelian pro-p-extension of K unramified outside S. This paper treats the case where S does not contain p and k is the rational number field or an imaginary quadratic field. In this case, we prove the explicit formulae for the free ranks of the S-ramified Iwasawa modules as abelian pro-p groups, by using Brumer's p-adic version of Baker's theorem on the linear independence of logarithms of algebraic numbers

Cholecystokinin receptor antagonist, loxiglumide, inhibits invasiveness of human pancreatic cancer cell lines

AbstractRecently, cholecystokinin has been reported to be important in regulating the growth of pancreatic cancer. We investigated the effect of loxiglumide (LXG), a cholecytskinin receptor antagonist, on the invasiveness of two human pancreatic cancer cell lines. Cells were treated with LXG for 24 h, and examined in the invasion assay. The expression and activity of MMP-9 in supernatants from cancer cells were analyzed by Western blotting and zymogram. Interestingly, the invasiveness of cancer cells and expression of MMP-9 were decreased by LXG in a dose-dependent manner. LXG may be a useful therapeutic agent against pancreatic cancer

ASCA Observations of the Supernova Remnant IC 443: Thermal Structure and Detection of Overionized Plasma

We present the results of X-ray spatial and spectral studies of the ``mixed-morphology'' supernova remnant IC 443 using ASCA. IC 443 has a center-filled image in X-ray band, contrasting with the shell-like appearance in radio and optical bands. The overall X-ray emission is thermal, not from a synchrotron nebula. ASCA observed IC 443 three times, covering the whole remnant. From the image analysis, we found that the softness-ratio map reveals a shell-like structure. At the same time, its spectra require two (1.0 keV and 0.2 keV) plasma components; the emission of the 0.2 keV plasma is stronger in the region near the shell than the center. These results can be explained by a simple model that IC 443 has a hot (1.0 keV) interior surrounded by a cool (0.2 keV) outer shell. From the emission measures, we infer that the 0.2 keV plasma is denser than the 1.0 keV plasma, suggesting pressure equilibrium between the two. In addition, we found that the ionization temperature of sulfur, obtained from H-like K$\alpha$ to He-like K$\alpha$ intensity ratio, is 1.5 keV, significantly higher than the gas temperature of 1.0 keV suggested from the continuum spectrum. The same can be concluded for silicon. Neither an additional, hotter plasma component nor a multi-temperature plasma successfully accounts for this ratio, and we conclude that the 1.0 keV plasma is overionized. This is the first time that overionized gas has been detected in a SNR. For the gas to become overionized in the absence of a photoionizing flux, it must cool faster than the ions recombine. Thermal conduction from the 1.0 keV plasma to the 0.2 keV one could cause the 1.0 keV plasma to become overionized, which is plausible within an old (3$\times10^4$ yr) SNR.Comment: 11 pages, 15 figures, 2 tables, accepted for publication in The Astrophysical Journa

Patient-derived ovarian cancer organoids capture the genomic profiles of primary tumours applicable for drug sensitivity and resistance testing

The use of primary patient-derived organoids for drug sensitivity and resistance testing could play an important role in precision cancer medicine. We developed expandable ovarian cancer organoids in<3 weeks; these organoids captured the characteristics of histological cancer subtypes and replicated the mutational landscape of the primary tumours. Seven pairs of organoids (3 high-grade serous, 1 clear cell, 3 endometrioid) and original tumours shared 59.5% (36.1-73.1%) of the variants identified. Copy number variations were also similar among organoids and primary tumours. The organoid that harboured the BRCA1 pathogenic variant (p.L63*) showed a higher sensitivity to PARP inhibitor, olaparib, as well as to platinum drugs compared to the other organoids, whereas an organoid derived from clear cell ovarian cancer was resistant to conventional drugs for ovarian cancer, namely platinum drugs, paclitaxel, and olaparib. The overall success rate of primary organoid culture, including those of various histological subtypes, was 80% (28/35). Our data show that patient-derived organoids are suitable physiological ex vivo cancer models that can be used to screen effective personalised ovarian cancer drugs