70 research outputs found

    Role of the expression of collagen prolyl-4-hydroxylase α subunits 1 and 2 in the development and prognosis of breast cancer

    Get PDF
     Background: The expression of prolyl-4-hydroxylase (P4H), an enzyme involved in collagen biosynthesis, is significantly upregulated during breast cancer development and progression. However, the molecular mechanisms by which P4H expression in cancer cells induces progression have not been elucidated. Thus, we aimed to determine the significance of the expression of isoforms 1 and 2 of P4H in breast cancer. Methods: We performed immunohistochemical analysis for P4HA1 and P4HA2 on the tumor samples obtained from 182 patients with breast cancer and examined the correlation between clinicopathological factors and markers related to epithelial-mesenchymal transition and ischemia. Protein expression levels were investigated using western blotting. In addition, breast cancer cell cultures were used to characterize the expression. Results: Expression of both P4HA1 and P4HA2 was upregulated in cancer cells compared with that in normal mammary glands; the high-P4H expression group tended to have a poorer prognosis than the low-P4H expression group. In particular, P4HA2 was strongly associated with tumor grade; P4HA2 expression showed a weak negative correlation with HIF-2α expression. In cultured breast cancer cells, the immunohistological expression of P4H and HIF increased tovarious degrees under hypoxia, while P4H protein levels increased in a time-dependent manner.  Conclusion: P4HA2 can be used as a marker of breast cancer grade and a prognostic factor. Differential expression of P4HA1 and P4HA2 was observed in an ischemic environment,suggesting that each may be affected by the type of collagen involved

    Temporal subtraction CT with nonrigid image registration improves detection of bone metastases by radiologists: results of a large-scale observer study

    Get PDF
    To determine whether temporal subtraction (TS) CT obtained with non-rigid image registration improves detection of various bone metastases during serial clinical follow-up examinations by numerous radiologists. Six board-certified radiologists retrospectively scrutinized CT images for patients with history of malignancy sequentially. These radiologists selected 50 positive and 50 negative subjects with and without bone metastases, respectively. Furthermore, for each subject, they selected a pair of previous and current CT images satisfying predefined criteria by consensus. Previous images were non-rigidly transformed to match current images and subtracted from current images to automatically generate TS images. Subsequently, 18 radiologists independently interpreted the 100 CT image pairs to identify bone metastases, both without and with TS images, with each interpretation separated from the other by an interval of at least 30 days. Jackknife free-response receiver operating characteristics (JAFROC) analysis was conducted to assess observer performance. Compared with interpretation without TS images, interpretation with TS images was associated with a significantly higher mean figure of merit (0.710 vs. 0.658; JAFROC analysis, P = 0.0027). Mean sensitivity at lesion-based was significantly higher for interpretation with TS compared with that without TS (46.1% vs. 33.9%; P = 0.003). Mean false positive count per subject was also significantly higher for interpretation with TS than for that without TS (0.28 vs. 0.15; P < 0.001). At the subject-based, mean sensitivity was significantly higher for interpretation with TS images than that without TS images (73.2% vs. 65.4%; P = 0.003). There was no significant difference in mean specificity (0.93 vs. 0.95; P = 0.083). TS significantly improved overall performance in the detection of various bone metastases

    Formation and Structure of the Barotropic Flow over the Shallow Shelf Slope Region

    Get PDF
    The formation and structure of the steady barotoropic flow over the shallow shelf slope are investigated using the theory with linear bottom friction and the numerical experiments with quadratic bottom friction. The barotropic flow over the shallow shelf slope, which is controlled by the bottom friction, has the balance between bottom stress curl and vortex stretching of water column. Such flow cannot conserve its volume transport to the downstream due to the onshore or offshore flow. The formation of barotoropic flow is related with the coastal-trapped wave propagation, i.e., Kelvin wave or topographic Rossby wave, during the transient period like as the geostropic adjustment. Therefore, the steady barotropic flow is formed in the direction of wave propagation, i.e., at the right hand sidewall to the source of disturbance in the northern hemisphere. By using the numerical model in which the ideal topography around the Tsushima/Korea Strait is taken into account and the flow system is driven by the sea level difference between the East China Sea and the Japan Sea, the flow patterns in winter are considered. In result, two branches in the central part of the East China Sea can be simulated. One northward branch is clockwise-flow along the isobaths in the northern part of the East China Sea and the other eastward branch directly inflows into the Tsushima/Korea Strait. Key words: barotoropic flow, shallow shelf slope, bottom frictio

    Decadal Response of Marine Food-chain to Bottom-up and Top-down Controls

    Get PDF

    Tsushima Current Mode Water (TCMW)

    Get PDF

    Pseudo-fortnightly variation produced by interaction between passage-flow and diurnal tidal currents in the Tsugaru Strait

    Get PDF
    We examine the reason why non-equilibrium response of lunar fortnightly tide, i.e., Mf tide with 13.7-day period, dominates in the Japan/East Sea including the Tsugaru Strait. In the present study, tides combining with passage-flow through the (Tsugaru) Strait are numerically simulated with a two-dimensional form of hydrodynamic model. It has been known that nonlinear interaction of dominant diurnal constituents K1 and O1 results in new oscillation with the same period of Mf tide. Analysis of computed sea level and currents is aimed primarily at describing the enhanced currents and patterns of energy flow in the Strait. Next, the focus of our model study is investigation of mechanisms of pseudo-fortnightly current enhancement where passage-flow interacts with diurnal current variations, resulting in temporal change in the friction due to “form drag”. Thus, we combine the study for form drag of passage-flow with the hydrodynamic interactions of diurnal tidal currents to provide some insight into the locally generated fortnightly tidal forcing within the Strait

    10. Numerical Simulations of the Transport Process of Walleye Pollock Eggs into Funka Bay

    Get PDF
    Ⅰ. Physical, Chemical Environment, Primary Production, Zooplankton and Their Coupling Model Studie
    corecore