Diagnostic Role of 18F-Fluorodeoxyglucose Positron Emission Tomography in Gastric Mesenchymal Tumors

There have been no comparative studies investigating the results of 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) in patients with gastric mesenchymal tumors, including leiomyomas, leiomyosarcomas, schwannomas, and gastrointestinal stromal tumors (GISTs). We retrospectively reviewed the data of 142 patients with pathologically diagnosed gastric mesenchymal tumors treated at 11 institutions. We analyzed the correlation between the maximum standardized uptake value (SUVmax) evaluated using fluorodeoxyglucose-positron emission tomography (FDG-PET) and the tumor size. The correlation between the SUVmax and mitotic index was also investigated in GISTs. The SUVmax (mean +/- standard deviation) was 0.5 +/- 0.6 in very low-risk GISTs (n = 42), 2.1 +/- 0.7 in low-risk GISTs (n = 26), 4.9 +/- 0.8 in intermediate-risk GISTs (n = 22), 12.3 +/- 0.8 in high-risk GISTs (n = 20), 1.0 +/- 1.0 in leiomyomas (n = 15), 6.9 +/- 1.2 in schwannomas (n = 10), and 3.5 in a leiomyosarcoma (n = 1). The SUVmax of GISTs with an undetermined risk classification was 4.2 +/- 1.3 (n = 8). Linear associations were observed between the SUVmax and tumor size in GISTs, leiomyomas, and schwannomas. The SUVmax of GISTs with a high mitotic index was significantly higher than that of GISTs with a low mitotic index (9.6 +/- 7.6 vs. 2.4 +/- 4.2). In conclusion, we observed positive correlations between the SUVmax and tumor size in GISTs, leiomyomas, and schwannomas. The SUVmax also positively correlated with the mitotic index and risk grade in GISTs. Schwannomas showed a higher FDG uptake than GISTs and leiomyomas

Numerical simulations on the relative importance of starbursts and AGN in ultra-luminous infrared galaxies

We investigate the relative importance of starbursts and AGN in nuclear activities of ultra-luminous infrared galaxies (ULIRGs) based on chemodynamical simulations combined with spectrophotometric synthesis codes. We numerically investigate both the gas accretion rates (m_acc) onto super massive black holes (SMBHs) and the star formation rates (m_sf) in ULIRGs formed by gas-rich galaxy mergers and thereby discuss what powers ULIRGs. Our principal results, which can be tested against observations, are as follows. (1) ULIRGs powered by AGN can be formed by major merging between luminous, gas-rich disk galaxies with prominent bulges containing SMBHs, owing to the efficient gas fuelling m_acc > 1 M_sun/yr of the SMBH. AGN in these ULIRGs can be surrounded by compact poststarburst stellar populations (e.g., A-type stars). (2) ULIRGs powered by starbursts with m_sf ~ 100 M_sun/yr can be formed by merging between gas-rich disk galaxies with small bulges having the bulge-to-disk-ratio (f_b) as small as 0.1. (3) The relative importance of starbursts and AGN can depend on physical properties of merger progenitor disks, such as f_b, gas mass fraction, and total masses. For example, more massive galaxy mergers are more likely to become AGN-dominated ULIRGs. (4) For most models, major mergers can become ULIRGs, powered either by starbursts or by AGN, only when the two bulges finally merge. Interacting disk galaxies can become ULIRGs with well separated two cores (> 20kpc) at their pericenter when they are very massive and have small bulges. (5) Irrespective of the choice of model, interacting/merging galaxies show the highest accretion rates onto the central SMBHs, and the resultant rapid growth of the SMBHs occur when their star formation rates are very high.Comment: 18 pages, 15 figures (f1.jpg for color figure of figure 1), accepted in MNRA

Loss of runt-related transcription factor 3 expression leads hepatocellular carcinoma cells to escape apoptosis

Background: Runt-related transcription factor 3 (RUNX3) is known as a tumor suppressor gene for gastric cancer and other cancers, this gene may be involved in the development of hepatocellular carcinoma (HCC). Methods: RUNX3 expression was analyzed by immunoblot and immunohistochemistry in HCC cells and tissues, respectively. Hep3B cells, lacking endogenous RUNX3, were introduced with RUNX3 constructs. Cell proliferation was measured using the MTT assay and apoptosis was evaluated using DAPI staining. Apoptosis signaling was assessed by immunoblot analysis. Results: RUNX3 protein expression was frequently inactivated in the HCC cell lines (91%) and tissues (90%). RUNX3 expression inhibited 90 +/- 8% of cell growth at 72 h in serum starved Hep3B cells. Forty-eight hour serum starvation-induced apoptosis and the percentage of apoptotic cells reached 31 +/- 4% and 4 +/- 1% in RUNX3-expressing Hep3B and control cells, respectively. Apoptotic activity was increased by Bim expression and caspase-3 and caspase-9 activation. Conclusion: RUNX3 expression enhanced serum starvation-induced apoptosis in HCC cell lines. RUNX3 is deleted or weakly expressed in HCC, which leads to tumorigenesis by escaping apoptosis

Transformation of Tri-Titanium(IV)-Substituted α-Keggin Polyoxometalate (POM) into Tetra-Titanium(IV)-Substituted POMs : Reaction Products of Titanium(IV) Sulfate with the Dimeric Keggin POM Precursor under Acidic Conditions

Reaction products of titanium(IV) sulfate in HCl-acidic aqueous solution with the dimeric species linked through three intermolecular Ti-O-Ti bonds of the two tri-titanium(IV)-substituted α-Keggin polyoxometalate (POM) subunits are described. Two novel titanium(IV)-containing α-Keggin POMs were obtained under different conditions. One product was a dimeric species through two intermolecular Ti-O-Ti bonds of the two tetra-titanium(IV)-substituted α-Keggin POM subunits, i.e., [[{Ti(H2O)3}2(μ-O)](α-PW9Ti2O38)]26- (1). The other product was a monomeric α-Keggin species containing the tetra-titanium(IV) oxide cluster and two coordinated sulfate ions, i.e., [{Ti4(μ-O)3(SO4)2(H2O)8}(α-PW9O34)]3- (2). Molecular structures of 1 and 2 were also discussed based on host (lacunary site)-guest (titanium atom) chemistry

The Effect of Extracurricular Career Assistance Courses : A Case of the Department of Natural Environment at Akita University

学部や選修は，学生の就職に対して責任を有している．しかしながら, 2003年度以前は，自然環境選修としての就職に関する取り組みは少なく，就職状況が余り良くなかった．そこで，就職率向上を目指し「就職ゼミ」を立ち上げ，実践的で個別的な就職支援活動への取り組みをおこなった． 　毎週１回の就職対策講座をメインに，就職模擬試験・個別指導・就職活動に関する情報 提供などを実施し，選修に所属する学生の就職活動に対する意識向上と，必要なスキルの向上を目指した．また，実際に就職活動をおこなった学生から情報収集を行い，より実践的な内容となるよう，常時「就職ゼミ」の構成に修正を加えている． 　その結果, 2005年度４年次学生については，就職ゼミ開始前よりも，学部内就職内定獲得順位が上昇し，民間企業就職希望者の半数内定取得時期が，学部全体を上回るペースで早くなった．また, 2005年度３年次学生については，ゼミ改善の結果，前年度学生よりもSPI模擬試験の点数が向上し，志望企業選択基準指標等に見られる就職意識の向上も見られた．このように，就職ゼミによって，就職実績，学生のスキル，学生の意識について，以前と比べ大きく状況を改善させることができたことは評価できる