On the Maze-like Domain Structure

The structure of closure domains bounded by zigzag shaped boundaries is investigated. Present theory explains well the general feature of the zigzag boundaries between mazelike domains observed by Chikazumi et al. The degree of zigzag depends on the magnitude of internal stress in the surface layer of the crystal. From the relation between zigzag angle and the internal stress, the magnitude of internal stress in the vicinity of the scratch drawn on the crystal surface is estimated

After-Effect of Magnetostriction in Nickel

Magnetostrictive after-effect of nickel was observed, which appeared immediately after the completion of the change in applied magnetic field. Transient change in magnetostrictive deformation continues over several minutes and amounts to about 10 per cent of the saturation value of magnetostriction of nickel. The decay curve of this after-effect is fitted to the expression, ε=C log (t/t_0+1), where ε is the amount of strain at time t in the course of the after-effect

The Effect of Plastic Deformation on the Coercive Force and Initial Permeability of Nickel Single Crystals

In order to study the effect of plastic deformation on the magnetic properties of ferromagnetic materials, the initial permeability and coercive force of nickel single crystals stretched stepwise up to 50% in shear strain have been measured, by means of the ballistic method at various temperatures ranging from -196℃ to 200℃. It has been found that the initial permeability shows a minimum, while the coercive force reveals a maximum near room temperature and this peak moves toward the lower temperature with increasing strain. The application of our theory developed in the preceding paper to these experimental results shows that the dislocation density, N, calculated from the observed values of the coercive force is connected with the shear stress, τ, by the following relations τ-τ_0～N in stage I, τ-τ_0-N^ in stage II and III, where τ_0, is the critical shear stress. Further, for explaining the change in initial permeability with plastic deformation, the flexibleness of the domain walls is discussed

Recovery of Coercive Force of Nickel

The effect of annealing on the coercive force of cold-worked nickel was investigated. The coercive force decreased approximately in proportion to the logarithm of annealing time, which was interpreted by the formal theory of recovery based on the viewpoint that the decrease in coercive force resulted from the vanishment of dislocations. The activation energy obtained from the present experiment was the same in the order of magnitude as that for climbing of a dislocation

E-cadherin遺伝子検出による胃癌のリンパ節転移診断

金沢大学医学部附属病院E-cadherinは上皮特異的接着分子として知られているが、胃癌の微量なリンパ節転移の早期診断をすることを目的に、郭清されたリンパ節におけるE-cadherin遺伝子のmRNA由来のcDNAを増幅させることによりその発現を検索した。胃癌症例12人を対象として、手術時に郭清されたリンパ節を速やかに取り出し二分し、半分はhematoxylin-eosin染色による病理組織学的検索を行い、半分は冷結保存した。冷結したリンパ節からt-RNAを抽出し、得られたRNAを用いて逆転写反応を行いcDNAを作製後polymerase chain reactionにより、E-cadherinのmRNA由来のcDNAを増幅した。さらにこれらのPCR(PCR)産物を電気泳動にかけた後、southern blot hybridization法にて検出した。すべての症例は肝転移、腹膜播種を伴わない早期胃癌患者であった。採取されたリンパ節計50個のうち病理組織学的にリンパ節転移陽性と判定されたものは2例4個に認められ、陽性率は8%(4/50)であった。一方E-cadherin mRNAの発現が認められたリンパ節は2例8個に認められ、陽性率は16%(8/50)であった。これらの中4個は病理組織学的にリンパ節転移陽性と判定されたものであり、他の4個は病理組織学的にはリンパ節転移陰性と判定されたものであった。現在全ての症例はリンパ節再発や他の血行性再発などは認めず健在である。以上よりリンパ節のE-cadherin mRNAの発現の検索によりリンパ節転移の陽性率は8%から16%に増加したことになり、本法はリンパ節転移の早期診断に有用と考えられた。研究課題/領域番号:07770980, 研究期間(年度):1995出典：研究課題「E-cadherin遺伝子検出による胃癌のリンパ節転移診断」課題番号07770980（KAKEN：科学研究費助成事業データベース（国立情報学研究所）） （https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-07770980/）を加工して作

ラット胃発癌におけるアラキドン酸代謝酵素の関与と阻害剤による化学予防

十二指腸液逆流が食道、胃さらに残胃などの前腸に発癌を引き起こすことが示唆されているが、その過程にcyclooxygenase 2(COX2)の関与が指摘されている。そこで、ラットを用いて十二指腸液を胃内へ逆流させる胃発癌モデルを作成して、胃の粘膜の変化、胃粘膜におけるCOX2の発現を調べるとともに、選択的COX2阻害剤による発癌抑制効果を観察した。7週齢のF334雄性ラットを用いて、エーテル麻酔下に十二指腸胃逆流モデルを作成した。すなわち、空腸を起始部から約1cmの部位で結紮切断し、肛門側空腸端を腺胃の大弯側に吻合した。今回、COX2阻害剤として、meloxicam(日本ベーリンガーインゲルハイム社)を使用し、通常の飼料に混餌投与した。なお発癌剤はいっさい投与しなかった。実験群は以下の3群を設定した。I、手術単独群 術後meloxicamは投与せず、通常の飼料を術後50週目まで投与する。II、Meloxicam投与群 術後2週目よりmeloxicamを2.0mg/kgの濃度で開始し、術後50週目まで投与する。III、非手術群 手術を行わずにmeloxicamを2.0mg/kgの濃度で開始し、48週目まで投与する。手術後20,30,40,50,60週目にラットをそれぞれ、I群は10,15,13,16,21頭、II群は10,20,13,14,19頭を屠殺して、病理組織学的検討を行った。前癌病変とされるgastritis cystica profunda(GCP)の発生率は20,30,40,50,60週目の順に、I群が60%,80%,92%,100%,100%、II群が30%,45%,38%,36%,32%と30週目以降II群の方が有意に発生率は低かった。また腺腫の発生率はI群の0%,0%,23%,50%,52%に比較して、II群では全期間0%と発生は認められず、50週目と60週目には有意差が認められた。一方、胃癌の20,30,40,50,60週目における発生率はI群の0%,0%,0%,25%,29%に比較して、II群では腺腫と同様、全期間発生は認められず、60週目には有意差が認められた。COX2の発現はGCP、腺腫、胃癌に認められたのみならず、間質細胞にも認められた。胃底腺領域におけるKi67 labeling indexは全ての時期において、I群の方がII群より有意に高率であった。COX2 mRNAの発現は両群に差は認められなかったが、PGE2産生量はI群の方がII群より高値であった。以上より、選択的COX2阻害剤meloxicamはラットの十二指腸胃逆流モデルにおいて、GCP、腺腫及び胃癌の発生を抑制していることが示唆された。その機序として、meloxicamがCOX2を介するPGE2産生を低下させることにより、上皮細胞の増殖活性を抑制することが、一因として考えられた。今後はヒトにおける胃癌の化学予防への可能性を検討していきたい。The aims of this study are to investigate the relationship between gastric carcinogenesis by duodenogastric reflux and cyclooxygenase 2 (COX-2) expression, and to disclose the chemopreventive effect of a specific COX-2 inhibitor, meloxicam (MLX) to the development of gastric cancer. The rats surgically undergoing duodenogastric reflux were allocated to two groups, given commercial chow (Control group) and experimental chow containing MLX (0.5 mg/Kg body weight/day) (MLX group). The animals were sacrificed postoperatively at 20, 30, 40, 50, and 60 weeks. The incidence of gastritis cystica profunda (GCP), precancerous lesion, in the MLX group was significantly lower after the 30th weak than in the control group (32% vs 100%). The incidences of adenoma and adenocarcinoma in the MLX group were also significantly lower than in the control group (0% vs 52%, in adenoma, 0% vs 29%, in adenocarcinoma). The Ki-67 labeling index in the MLX group was significantly higher than in the control group through the whole experimental period. The COX-2 expression was immunohistochemically observed not only in the epithelium of GCP, adenoma and adenocarcinoma, but also in the stroma. The COX-2 mRNA expression did not differ between two groups but the level of PGE2 product in the MLX group was higher than in the control group. These results indicate that a specific COX-2 inhibitor, meloxicam, suppresses the development of GCP, adenoma and adenocarcinoma in the rodent model of gastric carcinogenesis by duodenogastric reflux, suspecting that the drug, which suppresses PGE2 production by COX-2 inhibition, prevents gastric carcinogenesis by reducing epithelial proliferation.研究課題/領域番号:14571183, 研究期間(年度):2002-2004出典：「ラット胃発癌におけるアラキドン酸代謝酵素の関与と阻害剤による化学予防」研究成果報告書　課題番号14571183 (KAKEN：科学研究費助成事業データベース（国立情報学研究所）)　　　本文データは著者版報告書より作

十二指腸液胃逆流によるラット胃発癌: 胆汁,膵液の分離逆流モデルによる検討

取得学位 : 博士（医学）, 学位授与番号 : 医博甲第968号, 学位授与年月日：平成2年12月31日,学位授与年：199

A Case of Microscopic Polyangiitis Following Mycoplasma Infection in a Patient with MPO-ANCA Positive Pulmonary Fibrosis

ABSTRACTBackgroundMicroscopic polyangiitis is a vasculitic disease that may result in a pulmonary renal syndrome. Anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis is strongly associated with infection.Case SummaryWe describe a case of microscopic polyangiitis that developed in a patient with MPO-ANCA positive pulmonary fibrosis following infection with mycoplasma. A renal biopsy was undertaken following the detection of microscopic hematuria during follow-up but no abnormal findings were evident. The MPO-ANCA titer increased following infection with mycoplasma pneumonia and a second renal biopsy demonstrated crescentic glomerulonephritis. The degree of pulmonary fibrosis was unaffected.DiscussionThe present case suggests that the mycoplasma infection triggered the elevation of MPO-ANCA titer and provoked glomerulonephritis in a patient with MPO-ANCA positive IPF. This case indicates the importance of testing for MPO-ANCA at the time of initial diagnosis, performing urinalysis and examining the urine sediment during follow-up and being alert to the potential onset of vasculitis in cases of pulmonary fibrosis

Conformational diversity of dynactin

Dynactin is a principal regulator of the minus-end directed microtubule motor dynein. The sidearm of dynactin is essential for binding to microtubules and regulation of dynein activity. Although our understanding of the structure of the dynactin backbone (Arp1 rod) has greatly improved recently, structural details of the sidearm subcomplex remain elusive. Here, we report the flexible nature and diverse conformations of dynactin sidearm observed by electron microscopy. Using nanogold labeling and deletion mutant analysis, we determined the domain organization of the largest subunit p150 and discovered that its coiled-coil (CC1), dynein-binding domain, adopted either a folded or an extended form. Furthermore, the entire sidearm exhibited several characteristic forms, and the equilibrium among them depended on salt concentrations. These conformational diversities of the dynactin complex provide clues to understanding how it binds to microtubules and regulates dynein