41 research outputs found

    Current status of tariff liberalization under regional trade agreements and the implications for the clarification of the discipline of GATT Article XXIV (Japanese)

    Get PDF
    This paper analyzes, with regard to regional trade agreements for trade in goods, the direction of the clarification of the discipline of future regional trade agreements, doing so by comparing the current discipline relating to consistency with the WTO and the debate that surrounds it, with the current status of the liberalization of tariffs under regional trade agreements. When regional trade agreements for trade in goods between developed countries or between developed countries and developing countries are concluded, based upon Article XXIV of the GATT they should eliminate duties and other restrictive regulations of commerce on "substantially all the trade within a reasonable length of time," and should not raise tariffs or other barriers to trade with regard to countries outside the region. However, the definitions of phrases such as "substantially all the trade" are not stated expressly. In addition, regional trade agreements between developing countries are regulated only as agreements on the mutual reduction or elimination of tariffs and non-tariff measures in enabling clauses, and do not impose any conditions for the elimination of tariffs for "substantially all the trade" or "within a reasonable length of time" as defined in Article XXIV of the GATT. In addition to the lack of clarity as regards the requirements in regional trade agreements relating to consistency with the GATT, the screening by the WTO of regional trade agreements that have been concluded could not be said to be functioning adequately. Amid the persistence of this uncertainty as to the discipline of regional trade agreements and how it is applied, the conclusion of such agreements is currently increasing in number. In order to avoid a flood of unregulated regional trade agreements, discussion of their discipline is underway within the rules negotiations in the WTO Doha Round, but there has been no convergence in the discussion of the conditions referred to above. This paper sets out the discussions to date in the WTO and other forums over intraregional conditions with regard to regional trade agreements, such as "substantially all the trade" and "within a reasonable length of time" in relation to tariffs. Then, with regard to major regional trade agreements already concluded and in effect, it verifies the current situation as regards the liberalization of tariffs in regional trade agreements from the viewpoint of conformity with these conditions. Conducting this empirical analysis enables me to study the impact that the state of tariff liberalization in regional trade agreements is having on the discussion about the clarification of discipline in the WTO rules negotiations, and to identify clues as to the future direction of the discussion at the WTO and proposals for disciplines that could realistically lead to agreement.

    Tissue-Tissue Interaction-Triggered Calcium Elevation Is Required for Cell Polarization during Xenopus Gastrulation

    Get PDF
    The establishment of cell polarity is crucial for embryonic cells to acquire their proper morphologies and functions, because cell alignment and intracellular events are coordinated in tissues during embryogenesis according to the cell polarity. Although much is known about the molecules involved in cell polarization, the direct trigger of the process remains largely obscure. We previously demonstrated that the tissue boundary between the chordamesoderm and lateral mesoderm of Xenopus laevis is important for chordamesodermal cell polarity. Here, we examined the intracellular calcium dynamics during boundary formation between two different tissues. In a combination culture of nodal-induced chordamesodermal explants and a heterogeneous tissue, such as ectoderm or lateral mesoderm, the chordamesodermal cells near the boundary frequently displayed intracellular calcium elevation; this frequency was significantly less when homogeneous explants were used. Inhibition of the intracellular calcium elevation blocked cell polarization in the chordamesodermal explants. We also observed frequent calcium waves near the boundary of the dorsal marginal zone (DMZ) dissected from an early gastrula-stage embryo. Optical sectioning revealed that where heterogeneous explants touched, the chordamesodermal surface formed a wedge with the narrow end tucked under the heterogeneous explant. No such configuration was seen between homogeneous explants. When physical force was exerted against a chordamesodermal explant with a glass needle at an angle similar to that created in the explant, or migrating chordamesodermal cells crawled beneath a silicone block, intracellular calcium elevation was frequent and cell polarization was induced. Finally, we demonstrated that a purinergic receptor, which is implicated in mechano-sensing, is required for such frequent calcium elevation in chordamesoderm and for cell polarization. This study raises the possibility that tissue-tissue interaction generates mechanical forces through cell-cell contact that initiates coordinated cell polarization through a transient increase in intracellular calcium

    間欺的低酸素はヒト神経細胞においてGATA転写因子を介してPOMCとCARTのmRNAを増加させる

    Get PDF
    Sleep apnea syndrome (SAS) is characterized by intermittent hypoxia (IH) during sleep. SAS and obesity are strongly related to each other. Here, we investigated the effect of IH on the expression of major appetite regulatory genes in human neuronal cells. We exposed NB-1, SH-SY5Y, and SK-N-SH human neuronal cells to IH (64 cycles of 5 min hypoxia and 10 min normoxia), normoxia, or sustained hypoxia for 24 h and measured the mRNA levels of proopiomelanocortin (POMC), cocaine- and amphetamine-regulated transcript (CART), galanin, galanin-like peptide, ghrelin, pyroglutamylated RFamide peptide, agouti-related peptide, neuropeptide Y, and melanocortin 4 receptor by real-time RT-PCR. IH significantly increased the mRNA levels of POMC and CART in all the neuronal cells. Deletion analysis revealed that the -705 to -686 promoter region of POMC and the -950 to -929 region of CART were essential for the IH-induced promoter activity. As possible GATA factor binding sequences were found in the two regions, we performed real-time RT-PCR to determine which GATA family members were expressed and found that GATA2 and GATA3 mRNAs were predominantly expressed. Therefore, we introduced siRNAs against GATA2 and GATA3 into NB-1 cells and found that GATA2 and GATA3 siRNAs abolished the IH-induced up-regulation of both POMC and CART mRNAs. These results indicate that IH stress up-regulates the mRNA levels of anorexigenic peptides, POMC and CART, in human neuronal cells via GATA2 and GATA3. IH can have an anorexigenic effect on SAS patients through the transcriptional activation of POMC and CART in the central nervous system.博士(医学)・甲第685号・平成30年6月27日© 2017 Elsevier Ltd. All rights reserved

    Coordination of Cell Polarity during Xenopus Gastrulation

    Get PDF
    Cell polarity is an essential feature of animal cells contributing to morphogenesis. During Xenopus gastrulation, it is known that chordamesoderm cells are polarized and intercalate each other allowing anterior-posterior elongation of the embryo proper by convergent extension (CE). Although it is well known that the cellular protrusions at both ends of polarized cells exert tractive force for intercalation and that PCP pathway is known to be essential for the cell polarity, little is known about what triggers the cell polarization and what the polarization causes to control intracellular events enabling the intercalation that leads to the CE. In our research, we used EB3 (end-binding 3), a member of +TIPs that bind to the plus end of microtubule (MT), to visualize the intracellular polarity of chordamesoderm cells during CE to investigate the trigger of the establishment of cell polarity. We found that EB3 movement is polarized in chordamesoderm cells and that the notochord-somite tissue boundary plays an essential role in generating the cell polarity. This polarity was generated before the change of cell morphology and the polarized movement of EB3 in chordamesoderm cells was also observed near the boundary between the chordamesoderm tissue and naïve ectoderm tissue or lateral mesoderm tissues induced by a low concentration of nodal mRNA. These suggest that definitive tissue separation established by the distinct levels of nodal signaling is essential for the chordamesodermal cells to acquire mediolateral cell polarity

    A design of a low-delay DPWM control circuit for DC-DC converter

    Get PDF
    A proposed design of a low-cost digital pulse width modulation (DPWM) control circuit for non-isolated DC-DC converter without A/D converter is described. Also, propsed realtime PID control technique for DPWM is described. Some experimental results and simulation results are revealed the proposed circuit and scheme. The purpose of this research is striking a balance between minimizing cost increase by digitalizing of the control circuit of DC-DC converter and speeding up the control circuit.INTELEC 07 - 29th International Telecommunications Energy Conference : Rome, Italy, 2007.09.30-2007.10.

    Tenosynovial Giant Cell Tumor Arising on the Scapular Region

    No full text
    Tenosynovial giant cell tumor (TSGCT) is a benign soft tissue tumor arising from the synovial membrane that composes the lining of joints, tendons and bursae. TSGCT is a common tumor occurring in the hands and fingers, and also consecutively in the knees, ankles, feet and hips. It is rarely found in the scapular region. To the best of our knowledge, only 2 cases arising on the upper back have been reported. This report presents the case of a 44-year-old Japanese female with a TSGCT arising on her right scapular region
    corecore