Differential expression of nuclear lamin subtypes in the neural cells of the adult rat cerebral cortex

Lamins are type V intermediate filament proteins that are located beneath the inner nuclear membrane. In mammalian somatic cells, LMNB1 and LMNB2 encode somatic lamins B1 and B2, respectively, and the LMNA gene is alternatively spliced to generate somatic lamins A and C. Mutations in lamin genes have been linked to many human hereditary diseases, including neurodegenerative disorders. Knowledge about lamins in the nervous system has been accumulated recently, but a precise analysis of lamin subtypes in glial cells has not yet been reported. In this study we investigated the composition of lamin subtypes in neurons, astrocytes, oligodendrocyte-lineage cells, and microglia in the adult rat cerebral cortex using an immunohistochemical staining method. Lamin A was not observed in neurons and glial cells. Lamin C was observed in astrocytes, mature oligodendrocytes and neurons, but not observed in oligodendrocyte progenitor cells. Microglia also did not stain positive for lamin C which differed from macrophages, with lamin C positive. Lamin B1 and B2 were observed in all glial cells and neurons. Lamin B1 was intensely positive in oligodendrocyte progenitor cells compared with other glial cells and neurons. Lamin B2 was weakly positive in all glial cells compared to neurons. Our current study might provide useful information to reveal how the onset mechanisms of human neurodegenerative diseases are associated with mutations in genes for nuclear lamin proteins

Theoretical Consideration on Influences of Cavity or Pillar Shape on Band Structures of Silicon-Based Photonic Crystals

This paper describes the physical manifestations of the various influences of cavity (or pillar) shape and the filling factor of dielectric material on band structures in two-dimensional photonic crystals. The influences of circular or rectangular cross-sections of cavity (or pillar) arrays on photonic band structures are considered theoretically, and significant aspects of square and triangular lattices are compared. It is shown that both the averaged dielectric constant of the photonic crystal and the distribution profile of photon energy play important roles in defining optical properties. For the triangular lattice, especially, it is shown that cavity array with a rectangular cross-section breaks the band structure symmetry. So, we go on to discuss this from the perspective of band structure, and consider the optical properties of a lattice with a circular cross-section cavity

遠隔操作による西之島海底の溶岩採取装置の開発 : 「TAIRIKUプロジェクト」大陸生成の新しい仮説と西之島における検証

西之島は活発な火山活動を続けているため，周辺4kmの立ち入りが禁止されている．その海域の水深10mの海底から溶岩を採取するため，遠隔操作が可能な溶岩採取機器の開発に着手した．機器の構成を紹介し，手動による動作試験の結果を報告する． 西之島は、2013年11月に40年ぶりに爆発的な噴火がはじまり、2014年10月現在も噴火は衰えを見せておらず、最近になって専門家からは数年規模で噴火継続する可能性も指摘されている。西之島噴火による現在までの総噴出量は7,000万m3と推定され、東西1.6km、南北1.7kmの島へと成長したが、活発な噴火活動のための、西之島近海は立入りが禁止されており、今回の噴火による噴出物は採取されていない。 一方、40年前の噴火で発生した噴出物や溶岩は採取され、大陸を形成する安山岩であることが確認されており、「なぜ海洋のど真ん中で大陸地殻を構成する安山岩マグマが噴出するのか？」という問いが残されている。 仮説検証のためには、西之島近海の溶岩試料を採取することが必須であるが、前述のとおり、有人での調査は困難な状況にある。そこで、そのための解決策として、本共同研究により、東京海洋大学の保有する電気推進船「らいちょうI」を改造した、遠隔操作が可能な自航型無人作業艇を開発し、溶岩試料の採取を目指す。作業艇には、ドレッジ・採泥器等の各種機器・ウインチ等を搭載し、西之島近海、水深10m前後の海底から今回の噴火によって生じた溶岩試料を採取する。海洋理工学会平成27年度春季大会（2015年5月25日～26日, 東京海洋大学品川キャンパス

Selective Elimination of NG2-Expressing Hair Follicle Stem Cells Exacerbates the Sensitization Phase of Contact Dermatitis in a Transgenic Rat Model

The hair cycle consists of three different phases: anagen (growth), catagen (regression), and telogen (resting). During the anagen phase, hair follicle stem cells (HFSCs) in the bulge and the secondary hair germ proliferate and generate the outer and inner root sheath cells and the hair shafts. We previously identified NG2-immunoreactive (NG2+) cells as HFSCs in both regions of the hair follicles. Recently, the interaction between the hair cycle and the cutaneous immune system has been re-examined under physiological and pathological conditions. However, the roles of NG2+ HFSCs in the skin’s immune system remain completely elucidated. In the present study, we investigated whether the elimination of NG2+ HFSCs affects the induction of allergic contact dermatitis, using a herpes simplex virus thymidine kinase (HSVtk)/ganciclovir (GCV) suicide gene system. When the GCV solution was applied to the skin of NG2-HSVtk transgenic (Tg) rats during the depilation-induced anagen phase, NG2+ HFSCs in the Tg rat skin induced apoptotic cell death. Under exposure of a hapten, the selective ablation of NG2+ HFSCs during the anagen phase aggravated the sensitization phase of allergic contact dermatitis. These findings suggest that NG2+ HFSCs and their progeny have immunosuppressive abilities during the anagen phase