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931.
Toshiyuki Shibata Jun Uzawa Yoshihiko Sugiura Kohei Hayashi Toshiharu Takizawa 《Chemistry and physics of lipids》1984,34(2):107-113
400 MHz 1H-resonances of 1-phosphatidyl-myoinositol (PI), PI 4-phosphate (DPI) and PI 4,5-bisphosphate (TPI) in CD3OD were assigned. Proton resonances in the inositol moiety shift downfield with the increase in the number of the phosphate from PI to TPI. From the 1H-1H and 1H-31P vicinal coupling constants, rotamer populations around bonds in the polar headgroups were calculated. The H-C(5)O-P bond at position 5 of the inositol moiety tends to assume a gauche form. The H-C(1)O-P and the H-C(4)O-P bonds are not so strongly restricted to the gauche form as the H-C(5)O-P bond. The conformation of the glycerol moiety in PI, DPI and TPI is similar to that in phosphotidylcholine (PC) and phosphatidylethanolamine (PE). The CH-CH2O-P bond in the glycerol moiety assumes a trans form. The acyl chains prefer a gauche arrangement to each other around the CHCH2OCOR bond. 相似文献
932.
Susan L. Makris Howard M. Solomon Ruth Clark Kohei Shiota Stephane Barbellion Jochen Buschmann Makoto Ema Michio Fujiwara Konstanze Grote Keith P. Hazelden Kok Wah Hew Masao Horimoto Yojiro Ooshima Meg Parkinson L. David Wise 《Birth defects research. Part B, Developmental and reproductive toxicology》2011,92(6):575-575
933.
Takashi Okubo Atsushi Toyoda Kohei Fukuhara Ikuo Uchiyama Yuhki Harigaya Megumi Kuroiwa Takuma Suzuki Yuka Murakami Yuichi Suwa Hideto Takami 《DNA research》2021,28(1)
We present here the second complete genome of anaerobic ammonium oxidation (anammox) bacterium, Candidatus (Ca.) Brocadia pituitae, along with those of a nitrite oxidizer and two incomplete denitrifiers from the anammox bacterial community (ABC) metagenome. Although reduction to NO is considered to be the first step in anammox, Ca. B. pituitae lacks nitrite reductase genes (nirK and nirS) responsible for this reaction. Comparative genomics of Ca. B. pituitae with Ca. Kuenenia stuttgartiensis and six other anammox bacteria with nearly complete genomes revealed that their core genome structure contains 1,152 syntenic orthologues. But nitrite reductase genes were absent from the core, whereas two other Brocadia species possess nirK and these genes were horizontally acquired from multiple lineages. In contrast, at least five paralogous hydroxylamine oxidoreductase genes containing candidate ones (hao2 and hao3) encoding another nitrite reductase were observed in the core. Indeed, these two genes were also significantly expressed in Ca. B. pituitae as in other anammox bacteria. Because many nirS and nirK genes have been detected in the ABC metagenome, Ca. B. pituitae presumably utilises not only NO supplied by the ABC members but also NO and/or NH2OH by self-production for anammox metabolism. 相似文献
934.
Hiromichi Morikawa Masahiro Nishihara Motoaki Seki Kohei Irifune 《Journal of plant research》1994,107(2):117-123
Significance of bombardment-mediated transformation in plant research is discussed. Apart from general subjects related to
this transformation study, a particular emphasis has been placed on the pollen and organelle transformation and on integration
mechanism. Over 70 literatures related to this field are cited here. 相似文献
935.
Hideto Osada Eriko Toda Kohei Homma Naymel A. Guzman Norihiro Nagai Mamoru Ogawa Kazuno Negishi Makoto Arita Kazuo Tsubota Yoko Ozawa 《Cell death & disease》2021,12(5)
Lipid metabolism-related gene mutations can cause retinitis pigmentosa, a currently untreatable blinding disease resulting from progressive neurodegeneration of the retina. Here, we demonstrated the influence of adiponectin receptor 1 (ADIPOR1) deficiency in retinal neurodegeneration using Adipor1 knockout (KO) mice. Adipor1 mRNA was observed to be expressed in photoreceptors, predominately within the photoreceptor inner segment (PIS), and increased after birth during the development of the photoreceptor outer segments (POSs) where photons are received by the visual pigment, rhodopsin. At 3 weeks of age, visual function impairment, specifically photoreceptor dysfunction, as recorded by electroretinography (ERG), was evident in homozygous, but not heterozygous, Adipor1 KO mice. However, although photoreceptor loss was evident at 3 weeks of age and progressed until 10 weeks, the level of visual dysfunction was already substantial by 3 weeks, after which it was retained until 10 weeks of age. The rhodopsin mRNA levels had already decreased at 3 weeks, suggesting that reduced rhodopsin may have contributed to early visual loss. Moreover, inflammation and oxidative stress were induced in homozygous KO retinas. Prior to observation of photoreceptor loss via optical microscopy, electron microscopy revealed that POSs were present; however, they were misaligned and their lipid composition, including docosahexaenoic acid (DHA), which is critical in forming POSs, was impaired in the retina. Importantly, the expression of Elovl2, an elongase of very long chain fatty acids expressed in the PIS, was significantly reduced, and lipogenic genes, which are induced under conditions of reduced endogenous DHA synthesis, were increased in homozygous KO mice. The causal relationship between ADIPOR1 deficiency and Elovl2 repression, together with upregulation of lipogenic genes, was confirmed in vitro. Therefore, ADIPOR1 in the retina appears to be indispensable for ELOVL2 induction, which is likely required to supply sufficient DHA for appropriate photoreceptor function and survival.Subject terms: Mechanisms of disease, Developmental neurogenesis 相似文献
936.
Kohei Satoh Norimichi Kan Takashi Okino Masaki Nakanishi Keiichi Mise Yasufumi Teramura Seiji Yamasaki Kazuhisa Ohgaki Takayoshi Tobe 《Cancer immunology, immunotherapy : CII》1991,32(5):273-279
Summary A murine plasmacytoma MOPC 104E (MOPC) is highly sensitive to chemotherapeutic agents such as cyclophosphamide and mitomycin C as well as to immunotherapy (OK-432-combined adoptive immunotherapy using interleukin-2-cultured killer cells). In the present study, we prepared cyclophosphamide-resistant MOPC cells (MOPC-CPA/R) by serial in vivo passage of tumor cells following cyclophosphamide treatment. The in vivo sensitivity of MOPC-CPA/R to mitomycin C or to immunotherapy (OK-432-combined adoptive immunotherapy) was significantly decreased compared to the parent MOPC. In vitro experiments showed that MOPC-CPA/R were more resistant (five-fold) to lysis by cultured immune spleen cells than MOPC. Inhibition of the lytic activity of cultured immune spleen cells against MOPC was significantly increased (P <0.05) by the addition of unlabeled MOPC compared to unlabeled MOPC-CPA/R. These results suggest that MOPC-CPA/R express weaker antigenicity than MOPC. However, the transfer of immune spleen cells cultured with tumor extract derived from MOPC-CPA/R significantly prolonged the survival of MOPC-CPA/R-inoculated mice. Thus, by repeated cyclophosphamide treatment, tumor cells with low-antigenicity were selected. These tumor cells had lower sensitivity to another chemotherapeutic agent and immunotherapy. Such an immunological response may play an important role in cancer therapy. 相似文献
937.
938.
939.
Kohei Yamauchi 《International Review of Hydrobiology》1990,75(6):859-860
Vitellogenesis in females and spermatogenesis in males were stimulated by exogeneous gonadotropic preparations. However, the subsequent oocyte maturation and spermiation did not advance because of the insuffiency of circulating 17α, 20β-dihydroxy-4-pregnen-3-one (17α, 20β-diOHprog). At the time of maturation, the injection of 17α, 20β-diOHprog induced oocyte maturation and ovulation in females and spermiation (increase in volume of seminal plasma and acquisition of sperm motility) in male. These results suggest strongly that 17α, 20β-diOHprog play a key role in the final maturation of the Japanese eel. 相似文献
940.
H. Okuyama Daisuke Enari Akira Shibahara Kohei Yamamoto N. Morita 《Archives of microbiology》1996,165(6):415-417
A cell-free extract of Pseudomonas sp. strain E-3 catalyzed the conversion of 9-cis-hexadecenoic acid [16:1(9c)] to 9-trans-hexadecenoic acid [16:1(9t)] in the free acid form and when 16:1(9c) was esterified to phosphatidylethanolamine (PE). The
cytosolic fraction catalyzed the isomerizations of free 16:1(9c) by itself and of 16:1(9c) esterified to PE in the presence
of the membrane fraction. Tracer experiments using [2,2-2H2]16:1(9c) demonstrated that the isomerization of free 16:1(9c) occurred independently of the isomerization of 16:1(9c) esterified
to PE, indicating that this bacterium has two types of activities that catalyze the cis-trans isomerization of the double bond of a mono-unsaturated fatty acid.
Received: 29 December 1995 / Accepted: 10 April 1996 相似文献