Observations of [C II] 158 micron Line and Far-infrared Continuum Emission toward the High-latitude Molecular Clouds in Ursa Major

We report the results of a rocket-borne observation of [C II] 158\micron line and far-infrared continuum emission at 152.5\micron toward the high latitude molecular clouds in Ursa Major. We also present the results of a follow-up observation of the millimeter ^{12}CO J=1-0 line over a selected region observed by the rocket-borne experiment. We have discovered three small CO cloudlets from the follow-up ^{12}CO observations. We show that these molecular cloudlets, as well as the MBM clouds(MBM 27/28/29/30), are not gravitationally bound. Magnetic pressure and turbulent pressure dominate the dynamic balance of the clouds. After removing the HI-correlated and background contributions, we find that the [C II] emission peak is displaced from the 152.5\micron and CO peaks, while the 152.5\micron continuum emission is spatially correlated with the CO emission. We interpret this behavior by attributing the origin of [C II] emission to the photodissociation regions around the molecular clouds illuminated by the local UV radiation field. We also find that the ratio of the molecular hydrogen column density to velocity-integrated CO intensity is 1.19+-0.29x10^{20} cm^{-2} (K kms^{-1})^{-1} from the FIR continuum and the CO data. The average [C II] /FIR intensity ratio over the MBM clouds is 0.0071, which is close to the all sky average of 0.0082 reported by the FIRAS on the COBE satellite. The average [C II]/CO ratio over the same regions is 420, which is significantly lower than that of molecular clouds in the Galactic plane.Comment: 15 pages, LaTeX (aaspp4.sty) + 2 tables(apjpt4.sty) + 6 postscript figures; accepted for publication in the Astrophysical Journal; Astrophys. J. in press (Vol. 490, December 1, 1997 issue

A Search for Near-Infrared Emission From the Halo of NGC 5907 at Radii of 10 kpc to 30 kpc

We present a search for near-infrared (3.5-5 micron) emission from baryonic dark matter in the form of low-mass stars and/or brown dwarfs in the halo of the nearby edge-on spiral galaxy NGC 5907. The observations were made using a 256 by 256 InSb array with a pixel scale of 17" at the focus of a liquid-helium-cooled telescope carried above the Earth's atmosphere by a sounding rocket. In contrast to previous experiments which have detected a halo around NGC 5907 in the V, R, I, J and K bands at galactic radii 6kpc < r < 10kpc, our search finds no evidence for emission from a halo at 10kpc < r < 30kpc. Assuming a halo mass density scaling as r^(-2), which is consistent with the flat rotation curves that are observed out to radii of 32kpc, the lower limit of the mass-to-light ratio at 3.5-5 microns for the halo of NGC 5907 is 250 (2 sigma) in solar units. This is comparable to the lower limit we have found previously for NGC 4565 (Uemizu et al. 1998). Based on recent models, our non-detection implies that hydrogen- burning stars contribute < 15% of the mass of the dark halo of NGC 5907. Our results are consistent with the previous detection of extended emission at r < 10kpc if the latter is caused by a stellar population that has been ejected from the disk because of tidal interactions. We conclude that the dark halo of NGC 5907, which is evident from rotation curves that extend far beyond 10kpc, is not comprised of hydrogen burning stars.Comment: 12 pages, LateX, plus 6 ps figures. Accepted by ApJ. minor changes, added references, corrected typo

Protective Effects of Radon Inhalation on Carrageenan-Induced Inflammatory Paw Edema in Mice

We assessed whether radon inhalation inhibited carrageenan-induced inflammation in mice. Carrageenan (1% v/v) was injected subcutaneously into paws of mice that had or had not inhaled approximately 2,000 Bq/m3 of radon for 24 h. Radon inhalation significantly increased superoxide dismutase (SOD) and catalase activities and significantly decreased lipid peroxide levels in mouse paws, indicating that radon inhalation activates antioxidative functions. Carrageenan administration induced paw edema and significantly increased tumor necrosis factor-alpha (TNF-α) and nitric oxide in serum. However, radon inhalation significantly reduced carrageenan-induced paw edema. Serum TNF-α levels were lower in the radon-treated mice than in sham-treated mice. In addition, SOD and catalase activities in paws were significantly higher in the radon-treated mice than in the sham-treated mice. These findings indicated that radon inhalation had anti-inflammatory effects and inhibited carrageenan-induced inflammatory paw edema

Snail accelerates cancer invasion by upregulating MMP expression and is associated with poor prognosis of hepatocellular carcinoma

We have previously demonstrated in an in vitro study that Snail increased the invasion activity of hepatoma cells by upregulating matrix metalloproteinase (MMP) gene expression. In the present study, we examined whether Snail gene expression correlates with cancer invasion and prognosis of patients with hepatocellular carcinoma (HCC). Quantitative reverse transcription–polymerase chain reaction (RT–PCR) was performed to evaluate Snail, E-cadherin, and MMP mRNA expressions in eight nodule-in-nodule tumours and 47 ordinary HCC tissues. In the nodule-in-nodule tumours, Snail expression significantly increased with tumour dedifferentiation (P=0.047). In the ordinary HCC tissues, Snail expression was significantly correlated with portal vein invasion (P=0.035) and intrahepatic metastasis (P=0.050); it also showed a significant correlation with MT1-MMP expression (r=0.572, P<0.001). In recurrence-free survival, the group with high Snail expression showed significantly poorer prognosis (P=0.035). Moreover, high Snail expression was an independent risk factor for early recurrence after curative resection. During the progression of HCC, Snail expression may be induced and accelerate invasion activity by upregulating MMP expression, resulting in portal invasion, intrahepatic metastasis, and poor prognosis

Comparative Study on the Inhibitory Effects of α-Tocopherol and Radon on Carbon Tetrachloride-Induced Renal Damage

Since the 2011 nuclear accident in Fukushima, the effects of low-dose irradiation, especially internal exposure, are at the forefront of everyone’s attention. However, low-dose radiation induced various stimulating effects such as activation of antioxidative and immune functions. In this study, we attempted to evaluate the quantitative effects of the activation of antioxidative activities in kidney induced by radon inhalation on carbon tetrachloride (CCl4)-induced renal damage. Mice were subjected to intraperitoneal (i.p.) injection of CCl4 after inhaling approximately 1000 or 2000 Bq/m3 radon for 24 h, or immediately after i.p. injection of α-tocopherol (100, 300, or 500 mg/kg bodyweight). In case of renal function, radon inhalation at a concentration of 2000 Bq/m3 has the inhibitory effects similar to α-tocopherol treatment at a dose of 300–500 mg/kg bodyweight. The activities of superoxide dismutase and catalase in kidneys were significantly higher in mice exposed to radon as compared to mice treated with CCl4 alone. These findings suggest that radon inhalation has an antioxidative effect against CCl4-induced renal damage similar to the antioxidative effects of α-tocopherol due to induction of antioxidative functions

Genome-Wide Identification of Polycomb Target Genes Reveals a Functional Association of Pho with Scm in Bombyx mori

Polycomb group (PcG) proteins are evolutionarily conserved chromatin modifiers and act together in three multimeric complexes, Polycomb repressive complex 1 (PRC1), Polycomb repressive complex 2 (PRC2), and Pleiohomeotic repressive complex (PhoRC), to repress transcription of the target genes. Here, we identified Polycomb target genes in Bombyx mori with holocentric centromere using genome-wide expression screening based on the knockdown of BmSCE, BmESC, BmPHO, or BmSCM gene, which represent the distinct complexes. As a result, the expressions of 29 genes were up-regulated after knocking down 4 PcG genes. Particularly, there is a significant overlap between targets of BmPho (331 out of 524) and BmScm (331 out of 532), and among these, 190 genes function as regulator factors playing important roles in development. We also found that BmPho, as well as BmScm, can interact with other Polycomb components examined in this study. Further detailed analysis revealed that the C-terminus of BmPho containing zinc finger domain is involved in the interaction between BmPho and BmScm. Moreover, the zinc finger domain in BmPho contributes to its inhibitory function and ectopic overexpression of BmScm is able to promote transcriptional repression by Gal4-Pho fusions including BmScm-interacting domain. Loss of BmPho expression causes relocalization of BmScm into the cytoplasm. Collectively, we provide evidence of a functional link between BmPho and BmScm, and propose two Polycomb-related repression mechanisms requiring only BmPho associated with BmScm or a whole set of PcG complexes