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31.
Essential role for TIRAP in activation of the signalling cascade shared by TLR2 and TLR4 总被引:25,自引:0,他引:25
Yamamoto M Sato S Hemmi H Sanjo H Uematsu S Kaisho T Hoshino K Takeuchi O Kobayashi M Fujita T Takeda K Akira S 《Nature》2002,420(6913):324-329
Signal transduction through Toll-like receptors (TLRs) originates from their intracellular Toll/interleukin-1 receptor (TIR) domain, which binds to MyD88, a common adaptor protein containing a TIR domain. Although cytokine production is completely abolished in MyD88-deficient mice, some responses to lipopolysaccharide (LPS), including the induction of interferon-inducible genes and the maturation of dendritic cells, are still observed. Another adaptor, TIRAP (also known as Mal), has been cloned as a molecule that specifically associates with TLR4 and thus may be responsible for the MyD88-independent response. Here we report that LPS-induced splenocyte proliferation and cytokine production are abolished in mice lacking TIRAP. As in MyD88-deficient mice, LPS activation of the nuclear factor NF-kappaB and mitogen-activated protein kinases is induced with delayed kinetics in TIRAP-deficient mice. Expression of interferon-inducible genes and the maturation of dendritic cells is observed in these mice; they also show defective response to TLR2 ligands, but not to stimuli that activate TLR3, TLR7 or TLR9. In contrast to previous suggestions, our results show that TIRAP is not specific to TLR4 signalling and does not participate in the MyD88-independent pathway. Instead, TIRAP has a crucial role in the MyD88-dependent signalling pathway shared by TLR2 and TLR4. 相似文献
32.
33.
Kodama R Norreys PA Mima K Dangor AE Evans RG Fujita H Kitagawa Y Krushelnick K Miyakoshi T Miyanaga N Norimatsu T Rose SJ Shozaki T Shigemori K Sunahara A Tampo M Tanaka KA Toyama Y Yamanaka T Zepf M 《Nature》2001,412(6849):798-802
Modern high-power lasers can generate extreme states of matter that are relevant to astrophysics, equation-of-state studies and fusion energy research. Laser-driven implosions of spherical polymer shells have, for example, achieved an increase in density of 1,000 times relative to the solid state. These densities are large enough to enable controlled fusion, but to achieve energy gain a small volume of compressed fuel (known as the 'spark') must be heated to temperatures of about 108 K (corresponding to thermal energies in excess of 10 keV). In the conventional approach to controlled fusion, the spark is both produced and heated by accurately timed shock waves, but this process requires both precise implosion symmetry and a very large drive energy. In principle, these requirements can be significantly relaxed by performing the compression and fast heating separately; however, this 'fast ignitor' approach also suffers drawbacks, such as propagation losses and deflection of the ultra-intense laser pulse by the plasma surrounding the compressed fuel. Here we employ a new compression geometry that eliminates these problems; we combine production of compressed matter in a laser-driven implosion with picosecond-fast heating by a laser pulse timed to coincide with the peak compression. Our approach therefore permits efficient compression and heating to be carried out simultaneously, providing a route to efficient fusion energy production. 相似文献
34.
Toyohisa Fujita Hao Chen Kai-tuo Wang Chun-lin He You-bin Wang Gjergj Dodbiba Yue-zhou Wei 《矿物冶金与材料学报》2021,28(2):179-192
The demand for Li-ion batteries (LIBs) for vehicles is increasing. However, LIBs use valuable rare metals, such as Co and Li, as well as environmentally toxic reagents. LIBs are also necessary to utilize for a long period and to recycle useful materials. The reduction, reuse, and recycle (3R) of spent LIBs is an important consideration in constructing a circular economy. In this paper, a flowsheet of the 3R of LIBs is proposed and methods to reduce the utilization of valuable rare metals and the amount of spent LIBs by remanufacturing used parts and designing new batteries considering the concept of 3R are described. Next, several technological processes for the reuse and recycling of LIBs are introduced. These technologies include discharge, sorting, crushing, binder removal, physical separation, and pyrometallurgical and hydrometallurgical processing. Each process, as well as the related physical, chemical, and biological treatments, are discussed. Finally, the problem of developed technologies and future subjects for 3R of LIBs are described. 相似文献
35.
Columns for visual features of objects in monkey inferotemporal cortex. 总被引:21,自引:0,他引:21
At early stages of the mammalian visual cortex, neurons with similar stimulus selectivities are vertically arrayed through the thickness of the cortical sheet and clustered in patches or bands across the surface. This organization, referred to as a 'column', has been found with respect to one-dimensional stimulus parameters such as orientation of stimulus contours, eye dominance of visual inputs, and direction of stimulus motion. It is unclear, however, whether information with extremely high dimensions, such as visual shape, is organized in a similar columnar fashion or in a different manner in the brain. Here we report that the anterior inferotemporal area of the monkey cortex, the final station of the visual cortical stream crucial for object recognition, consists of columns, each containing cells responsive to similar visual features of objects. 相似文献
36.
K. Fujita Y. Shimomura J. Fujita K. J. Mori 《Cellular and molecular life sciences : CMLS》1985,41(4):504-505
Summary Nude mice were inoculated with BMA1 cells. These are cells which produce granulocyte-macrophage colony stimulating factor (GM-CSF); They are derived from mouse bone marrow stromal cells transfected with adenovirus 5 DNA. Progressive neutrophilia developed as the tumor grew, but disappeared quickly after local tumor excision. Media conditioned with tumor cells had GM-CSF but neither erythropoietin, nor burst-promoting activity. In all the tumors which developed, focal areas of bone formation were found among fibrosarcomatous tissues. 相似文献
37.
Y. Nagao S. Takao E. Fujita C. Murayama T. Mori T. Asao T. Suzue 《Cellular and molecular life sciences : CMLS》1983,39(10):1116-1118
Summary New type hypoxic cell sensitizers, N1, N10-bis(4-nitrobenzoyl)spermidine (1) and N1,N14-bis(4-nitrobenzoyl)-spermine (2), have been developed. These compounds were shown to be more effective radiosensitizers to hypoxic cells than misonidazole (3). 相似文献
38.
Antitumor activity of the isodon diterpenoids: Structural requirements for the activity 总被引:1,自引:0,他引:1
E. Fujita Y. Nagao M. Node K. Kaneko S. Nakazawa H. Kuroda 《Cellular and molecular life sciences : CMLS》1976,32(2):203-206
Summary A significant antitumor activity of oridonin (1) and lasiokaurin (2), the kaurene-type diterpenoids ofIsodon species, was shown by their i.p. injection to the test mice inoculated by Ehrlich ascites carcinoma. Enmein (8), compounds9 and3 were also active under larger dose. Subsequently, the relationship between their chemical structure and antitumor activity was investigated, and the activity of oridonin (1) and lasiokaurin (2) was rationalized in terms of their structural feature. 相似文献
39.
Northern Hemisphere forcing of climatic cycles in Antarctica over the past 360,000 years 总被引:3,自引:0,他引:3
Kawamura K Parrenin F Lisiecki L Uemura R Vimeux F Severinghaus JP Hutterli MA Nakazawa T Aoki S Jouzel J Raymo ME Matsumoto K Nakata H Motoyama H Fujita S Goto-Azuma K Fujii Y Watanabe O 《Nature》2007,448(7156):912-916
The Milankovitch theory of climate change proposes that glacial-interglacial cycles are driven by changes in summer insolation at high northern latitudes. The timing of climate change in the Southern Hemisphere at glacial-interglacial transitions (which are known as terminations) relative to variations in summer insolation in the Northern Hemisphere is an important test of this hypothesis. So far, it has only been possible to apply this test to the most recent termination, because the dating uncertainty associated with older terminations is too large to allow phase relationships to be determined. Here we present a new chronology of Antarctic climate change over the past 360,000 years that is based on the ratio of oxygen to nitrogen molecules in air trapped in the Dome Fuji and Vostok ice cores. This ratio is a proxy for local summer insolation, and thus allows the chronology to be constructed by orbital tuning without the need to assume a lag between a climate record and an orbital parameter. The accuracy of the chronology allows us to examine the phase relationships between climate records from the ice cores and changes in insolation. Our results indicate that orbital-scale Antarctic climate change lags Northern Hemisphere insolation by a few millennia, and that the increases in Antarctic temperature and atmospheric carbon dioxide concentration during the last four terminations occurred within the rising phase of Northern Hemisphere summer insolation. These results support the Milankovitch theory that Northern Hemisphere summer insolation triggered the last four deglaciations. 相似文献
40.
Jin D Liu HX Hirai H Torashima T Nagai T Lopatina O Shnayder NA Yamada K Noda M Seike T Fujita K Takasawa S Yokoyama S Koizumi K Shiraishi Y Tanaka S Hashii M Yoshihara T Higashida K Islam MS Yamada N Hayashi K Noguchi N Kato I Okamoto H Matsushima A Salmina A Munesue T Shimizu N Mochida S Asano M Higashida H 《Nature》2007,446(7131):41-45
CD38, a transmembrane glycoprotein with ADP-ribosyl cyclase activity, catalyses the formation of Ca2+ signalling molecules, but its role in the neuroendocrine system is unknown. Here we show that adult CD38 knockout (CD38-/-) female and male mice show marked defects in maternal nurturing and social behaviour, respectively, with higher locomotor activity. Consistently, the plasma level of oxytocin (OT), but not vasopressin, was strongly decreased in CD38-/- mice. Replacement of OT by subcutaneous injection or lentiviral-vector-mediated delivery of human CD38 in the hypothalamus rescued social memory and maternal care in CD38-/- mice. Depolarization-induced OT secretion and Ca2+ elevation in oxytocinergic neurohypophysial axon terminals were disrupted in CD38-/- mice; this was mimicked by CD38 metabolite antagonists in CD38+/+ mice. These results reveal that CD38 has a key role in neuropeptide release, thereby critically regulating maternal and social behaviours, and may be an element in neurodevelopmental disorders. 相似文献