First-principles study on the origin of large thermopower in hole-doped LaRhO3 and CuRhO2

Based on first-principles calculations, we study the origin of the large thermopower in Ni-doped LaRhO3 and Mg-doped CuRhO2. We calculate the band structure and construct the maximally localized Wannier functions from which a tight binding Hamiltonian is obtained. The Seebeck coefficient is calculated within the Boltzmann's equation approach using this effective Hamiltonian. For LaRhO3, we find that the Seebeck coefficient remains nearly constant within a large hole concentration range, which is consistent with the experimental observation. For CuRhO2, the overall temperature dependence of the calculated Seebeck coefficient is in excellent agreement with the experiment. The origin of the large thermopower is discussed.Comment: 7 pages, to be published J. Phys.: Cond. Matt., Proc. QSD 200

The spotted gar genome illuminates vertebrate evolution and facilitates human-teleost comparisons

To connect human biology to fish biomedical models, we sequenced the genome of spotted gar (Lepisosteus oculatus), whose lineage diverged from teleosts before teleost genome duplication (TGD). The slowly evolving gar genome has conserved in content and size many entire chromosomes from bony vertebrate ancestors. Gar bridges teleosts to tetrapods by illuminating the evolution of immunity, mineralization and development (mediated, for example, by Hox, ParaHox and microRNA genes). Numerous conserved noncoding elements (CNEs; often cis regulatory) undetectable in direct human-teleost comparisons become apparent using gar: functional studies uncovered conserved roles for such cryptic CNEs, facilitating annotation of sequences identified in human genome-wide association studies. Transcriptomic analyses showed that the sums of expression domains and expression levels for duplicated teleost genes often approximate the patterns and levels of expression for gar genes, consistent with subfunctionalization. The gar genome provides a resource for understanding evolution after genome duplication, the origin of vertebrate genomes and the function of human regulatory sequences

胃癌リンパ節転移初期像の検討 : 見張りリンパ節を指標とした胃癌手術は有効か

胃癌外科治療におけるリンパ節廓清術は,術後QOLを考慮して,拡大廓清から縮小廓清の方向へ転化している.さらに近年では症例個々の癌病巣からのリンパ流を確認し,流れの最上流に位置するリンパ節をsentinel nodeとし,このリンパ節を術中病理検索して転移のない場合は,転移なしと考え縮小手術を行うsentinel node navigation surgeryが広く行われ始めている.しかし,本法はほとんどの症例で癌局在部位からのリンパ流が単一流でないと多数のリンパ節を術中に検索する必要性があり,また転移リンパ節を見落とす可能性がある.そこで今回我々は,胃癌においてリンパ節転移の初期症例として少数個リンパ節転移例を対象に,そのリンパ流が単一かを検討した. [対象]標準的2群リンパ節までの廓清が行われ治癒切除となった深達度ssまでの胃癌症例で,転移リンパ節個数が2個から4個までの145症例を対象とした. [結果]全症例の30～40%に複数のリンパ流によるリンパ節転移が存在し,早期癌においても30%, mp癌では38%, ss癌では41%に複数リンパ流による転移が存在した. [考察]胃癌はリンパの流れが多方向にあるため,すべてのsentinel nodeを同定することは困難と考えられた.In consideration of the quality of life of patients, there is a trend in gastric cancer surgery to perform limited rather than extended lymph node dissection. If a sentinel node dissected during surgery is negative for cancer cells pathologically, there is believed to be almost no chance of lymph node metastasis. In this study we focused on gastric cancer cases with lymph node metastasis in order to reveal whether the lymphatic flow is a single stream from the cancerous lesion. Of 145 gastric cancer cases, about 30-40% had lymph node metastasis by multiple routes, and 30% of m, sm cancer, 38% of mp cancer, and 41% of ss cancer cases had multiple routes. Multiple sentinel nodes were involved in gastric cancer, and thus we conclude that it is difficult to identify the sentinel node in gastric cancer

根治切除不能再発胃malignant GISTに対しSTI571が著効した1例

症例は40歳男性.胃malignant GIST原発巣切除術後再発をきたし,約2年6ヵ月の間に5回の再発巣切除を行った.しかし,再度再発し,骨盤から胸腔内まで多発転移巣を認め,腹部大動脈周囲を取り巻くように再発巣があることから根治切除不能と診断した.原発巣および切除転移巣の免疫染色においてc-kit陽性であったことからイマニチブの投与を開始した.6週間後の腹部CT検査において大動脈周囲転移巣の消失,肝転移巣,腹腔内転移巣の縮小,壊死化を認め,4ヵ月後の肝転移巣超音波下穿刺組織診において腫瘍細胞を認めなかった.これまでGISTに対する有効な化学療法はなかったがイマニチブの投与は再発GISTの治療において第一選択となる可能性があると考えられた.Gastrointestinal stromal tumors (GIST) have been considered chemoresistant, but recent reports have demonstrated the efficacy of STI571 (imatinib), a tyrosine kinase inhibitor, for c-kit positive GIST. We describe our experience with a patient with radically unresectable recurrent gastric GIST which significantly responded to STI571. A 40-year-old man underwent cardiectomy due to cardial submucosal tumor, which was diagnosed as malignant GIST by histopathology. However, this tumor relapsed in the abdominal cavity 15 months after the first surgery and the recurrent tumor was resected again. The patient experienced five relapses in the abdominal cavity and liver in about 30 months, and every time surgical resection was performed. Finally this patient was admitted for the seventh time due to tumors developing in the mesenterium and remnant liver in October 2001. Encouraged by recent successful clinical reports of STI571 against GIST, STI571 twice daily at 400 mg/day was administered orally, and CT scan at week 6 showed disappearance of the tumor surrounding the aorta, regression of the metastatic liver tumor and the tumor beside the spleen. Abdominal CT scan after 4 months showed further regression of the tumors. Aspiration cytology of metastatic liver tumor did not show any distinctive tumor cells. STI571 is thought to be a possible standard treatment for patients with GIST