トウカガタ ジシンケイ (ペネトレータ) ノ ナンキョク ミズホ コウゲン デノ シケン カンソク ダイ43ジ ナツタイ ホウコク

南極氷床上のクレバス帯等の,地上からは到達困難な地域での人工地震観測を目的とした投下型地震観測装置(南極ペネトレータ)を開発し,第43次日本南極地域観測隊で実施する東南極みずほ高原における人工地震探査で使用するために,22本のペネトレータを昭和基地に持ち込んだ.しかし,開発の遅れに伴う国内試験の不足から種々の不具合が発生し,今回は本観測での使用をあきらめざるを得なかった.当初の目的は果たすことができなかったが,国内では得られない環境でのペネトレータ投下実験を行い,投下姿勢,着地衝撃力,温度変化等の貴重なデータを得るとともに,南極内陸部での実際のヘリコプター運用への知見を得ることができた.これらの成果はペネトレータ型地震計の改良のみならず,今後の各種投下型観測機器の開発・製作に多いに役に立つものと考えられる.We have developed an Antarctic penetrator that is applicable to seismic explosion experiments along a difficult traverse route on a continental ice sheet with crevasses. In the 43rd Japanese Antarctic Research Expedition (JARE-43, 2001-2002) seismic explosion experiments on the Mizuho Plateau, in East Antarctica, we equipped 22 penetrators for seismic observation. However, due to electrical trouble, we could not apply the penetrators to actual observation. Then, we carried out a running test of the penetrators and acquired much valuable data that cannot be obtained in the domestic environment in Japan, such as the declination angle of a body intruding into the Antarctic ice sheet, impact shock, and daily change of temperature of the body in the snow. These data are not only useful for development of the Antarctic penetrator, but also for development of touchdown-type physical observation equipment for use in Antarctica

Nordic consensus report on asthma management

AbstractThe work with the Nordic consensus report on asthma management started some years ago. The Nordic countries have common socioeconomic conditions. We acknowledge the international as well as other European guidelines providing valuable recommendations. Nevertheless, we felt the need to combine the common Nordic experiences in order to have a local statement of asthma and asthma care, based upon Nordic clinical science and tradition. The work has been rewarding and we acknowledge many valuable contributions from paediatricians, allergologists and lung physicians in all Nordic countries. The response has so far been positive and we feel that the present material reflects the main opinion of Nordic physicians taking care of asthma patients of all ages. However, the asthma and allergy research field is rapidly developing. Thus, this document should merely be regarded as a time-limited contribution to the continuing scientific discussion of this fascinating field

Kif13b Regulates PNS and CNS Myelination Through the Dlg1 Scaffold

Microtubule-based kinesin motors have many cellular functions, including the transport of a variety of cargos. However, unconventional roles have recently emerged, and kinesins have also been reported to act as scaffolding proteins and signaling molecules. In this work, we further extend the notion of unconventional functions for kinesin motor proteins, and we propose that Kif13b kinesin acts as a signaling molecule regulating peripheral nervous system (PNS) and central nervous system (CNS) myelination. In this process, positive and negative signals must be tightly coordinated in time and space to orchestrate myelin biogenesis. Here, we report that in Schwann cells Kif13b positively regulates myelination by promoting p38γ mitogen-activated protein kinase (MAPK)-mediated phosphorylation and ubiquitination of Discs large 1 (Dlg1), a known brake on myelination, which downregulates the phosphatidylinositol 3-kinase (PI3K)/v-AKT murine thymoma viral oncogene homolog (AKT) pathway. Interestingly, Kif13b also negatively regulates Dlg1 stability in oligodendrocytes, in which Dlg1, in contrast to Schwann cells, enhances AKT activation and promotes myelination. Thus, our data indicate that Kif13b is a negative regulator of CNS myelination. In summary, we propose a novel function for the Kif13b kinesin in glial cells as a key component of the PI3K/AKT signaling pathway, which controls myelination in both PNS and CNS

Ultrastructure and Systematics of Two New Species of Dinoflagellate, Paragymnodinium Asymmetricum sp. nov. and Paragymnodinium Inerme sp. nov. (Gymnodiniales, Dinophyceae)(1)

The genus Paragymnodinium currently includes two species, P. shiwhaense and P. stigmaticum, that are characterized by mixotrophic nutrition and the possession of nematocysts. In this study, two new dinoflagellates belonging to this genus were described based on observations using LM, SEM, and TEM together with a molecular analysis. Cells of P. asymmetricum sp. nov., isolated from Nha Trang Beach, Vietnam, were 7.9-12.6 mu m long and 4.7-9.0 mu m wide. The species showed no evidence of feeding behavior and was able to sustain itself phototrophically. Paragymnodinium asymmetricum shared many features with P. shiwhaense, including presence of nematocysts, absence of an eyespot, and a planktonic lifestyle, but was clearly distinguished by the asymmetric shape of the hyposome, possession of a single chloroplast, and its nutritional mode. Cells of P. inerme sp. nov., isolated from Jogashima, Kanagawa Pref, Japan, were 15.3-23.7 mu m long and 10.9-19.6 mu m wide. This species also showed no evidence of feeding behavior. Paragymnodinium inerme was similar to cells of P. shiwhaense in shape and planktonic lifestyle, but its nutritional mode was different. The presence of incomplete nematocysts was also a unique feature. A phylogenetic analysis inferred from concatenated SSU and LSU rDNA sequences recovered the two dinoflagellates in a robust clade with Paragymnodinium spp., within the clade of Gymnodinium sensu stricto. This evidence, together with their morphological similarities, made it reasonable to conclude that these two dinoflagellates are new species of Paragymnodinium

Two types of spontaneous depolarizations in the interstitial cells freshly prepared from the murine small intestine

To explore the electrophysiological properties of the interstitial cells of Cajal (ICCs) and fibroblast-like cells (FLCs), we developed a new preparation by treating the murine small intestine with collagenase. This thin muscle layer preparation contained at least two types of interstitial cells around the enteric nerve bundles, and the cluster of smooth muscle cells displayed a rhythmic contraction. We morphologically identified ICCs and FLCs and conducted patch clamp experiments on each type of cell. The c-kit-positive CD34-negative ICCs showed spontaneous and rhythmic potential fluctuations, and a large transient inward current was evoked by depolarization under voltage clamp conditions. Once the inward current was triggered, it took a regenerative time course and lasted approximately 500 ms. The current was inactivated by continuous depolarization, and by removal of external Ca(2+). The application of acetylcholine (ACh) prolonged the duration of spontaneous depolarization as well as the depolarization-induced inward current. This inward current showed a reversal potential of around +3 mV and was considered to be due to non-selective cation channels. The c-kit-negative CD34-positive FLCs showed irregular or regular potential fluctuations, and spontaneous outward current was observed under voltage clamp conditions. This outward current showed a reversal potential of around −80 mV and might be classified as a potassium current. We failed to observe major time- and voltage-dependent currents except the above two currents in the interstitial cells

Observation tests of the Antarctic penetrator on the Mizuho Plateau in JARE-43 summer operation

We have developed an Antarctic penetrator that is applicable to seismic explosion experiments along a difficult traverse route on a continental ice sheet with crevasses. In the 43rd Japanese Antarctic Research Expedition (JARE-43, 2001-2002) seismic explosion experiments on the Mizuho Plateau, in East Antarctica, we equipped 22 penetrators for seismic observation. However, due to electrical trouble, we could not apply the penetrators to actual observation. Then, we carried out a running test of the penetrators and acquired much valuable data that cannot be obtained in the domestic environment in Japan, such as the declination angle of a body intruding into the Antarctic ice sheet, impact shock, and daily change of temperature of the body in the snow. These data are not only useful for development of the Antarctic penetrator, but also for development of touchdown-type physical observation equipment for use in Antarctica

MicroRNA-33 encoded by an intron of sterol regulatory element-binding protein 2 (Srebp2) regulates HDL in vivo

Sterol regulatory element-binding protein 2 (SREBP-2) transcription factor has been identified as a key protein in cholesterol metabolism through the transactivation of the LDL receptor and cholesterol biosynthesis genes. Here, we generated mice lacking microRNA (miR)-33, encoded by an intron of the Srebp2, and showed that miR-33 repressed the expression of ATP-binding cassette transporter A1 (ABCA1) protein, a key regulator of HDL synthesis by mediating cholesterol efflux from cells to apolipoprotein A (apoA)-I. In fact, peritoneal macrophages derived from miR-33–deficient mice showed a marked increase in ABCA1 levels and higher apoA-I–dependent cholesterol efflux than those from WT mice. ABCA1 protein levels in liver were also higher in miR-33–deficient mice than in WT mice. Moreover, miR-33–deficient mice had significantly higher serum HDL cholesterol levels than WT mice. These data establish a critical role for miR-33 in the regulation of ABCA1 expression and HDL biogenesis in vivo