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991.
Kazunobu Baba Haruka Morimoto Susumu Imaoka 《The Journal of biological chemistry》2013,288(25):18393-18405
Under pathological conditions such as ischemia-reperfusion, Nrf2 acts as a key regulator of cellular oxidative response. Provided that Nrf2 is sensitive to hypoxia during ischemia, Nrf2 may affect reactive oxygen species metabolism during reoxygenation. In this study, hypoxia suppressed Nrf2 protein, and its hypoxic suppression was not recovered with knockdown of the Nrf2 repressor Keap1. Moreover, an Nrf2 mutant lacking the Keap1 binding domain was suppressed under hypoxia, suggesting that Keap1 does not contribute to hypoxic Nrf2 suppression. HIF-1α and Siah2 are both key regulators of hypoxic responses. Hypoxia induced the Siah2 protein. Although inhibition or knockdown of Siah2 prevented the suppression of Nrf2, knockdown of HIF-1α did not. Moreover, Siah2 interacted with Nrf2 through a binding motif, suggesting that Siah2 contributes to the suppression of Nrf2. Some cytosolic kinases also play important roles in Nrf2 regulation. In this study, PKC phosphorylates serine residues of Nrf2 during hypoxia. Knockdown of Siah2 rescued hypoxic decreases in an Nrf2 mutant that mimicked phosphorylation at serine 40 or lacked this phosphorylation site, suggesting that Siah2 contributes to the degradation of Nrf2 irrespective of its phosphorylation status. Moreover, knockdown of Siah2 attenuated ubiquitination of the Nrf2 mutant, suggesting that association of Siah2 with Nrf2 causes proteasome-mediated degradation of Nrf2. 相似文献
992.
993.
A new species of the rare arietellid genus Scutogerulus is described from deep hyperbenthic waters off Okinawa, southwestern Japan. This is the second species of the genus. Phylogenetically significant characteristics known only on the basis of the type species are confirmed by the discovery of the new congener, in particular: (1) the genital system of the female exhibits the most plesiomorphic condition of any arietellid genus; (2) the well developed setae on the endopodal segments of the maxillae and maxillipeds are modified into ‘shield‐like setae’ similar to the ‘button setae’ in another arietelloidean family, the Augaptilidae; (3) the outer distal spine on the first exopodal segment of leg 1 is absent. 相似文献
994.
995.
The nature of the electron transfer and terminal oxidase(s)in the sulfite-oxidizing system of Thiobacillus thiooxidnaswas studied in detail with various artificial electron donorsand inhibitors. Thionine, when reduced by ascorbate, was mosteffectively oxidized by whole cells and the particulate fractionof the various artificial electron donors. p-PD and TMPD werescarcely oxidized by either intact cells or the particulatefraction. The optimum pH of the thionine-oxidizing activity by the particulatefraction was 7.0 and that of the sulfite-oxidizing activitywas 6.8. The Km values for thionine and sulfite were 7.6x105Mand 1.6xl04M, respectively. Sulfite oxidase activity in the particulate fraction was markedlyinhibited by amytal, rotenone, quinacrine-HGl and 2,4-DNP. HOQNOinhibited sulfite oxidase activity completely, but had no effecton thionine oxidase activity. Cyanide- and azide-insensitive respirations were present inthe particulate fraction. Thionine oxidase activity was inhibitedphoto-irreversibly with carbon monoxide, while sulfite oxidaseactivity showed photo-reversible carbon monooxide inhibition.The presence of two carbon monoxide-binding pigments was confirmedin the particulate fraction by a spectrophotometric study. (Received May 16, 1975; ) 相似文献
996.
Nicotiana repanda (n = 24) × N. tabacum (n = 24) was obtained by ovule culture following regeneration from the callus. The hybrid showed an aneuploid chromosome number (44) and morphological characteristics intermediate between those of N. repanda and N. tabacum. The resistance of N. repanda to tobacco mosaic virus was incorporated into the hybrid. 相似文献
997.
Androgen receptor gene mutations in human prostate cancer 总被引:13,自引:0,他引:13
Hiroyoshi Suzuki Naohide Sato Yoshio Watabe Motoyuki Masai Susumu Seino Jun Shimazaki 《The Journal of steroid biochemistry and molecular biology》1993,46(6):759-765
To investigate the structural abnormality of the androgen receptor (AR) in human prostate cancers, exons B-H encoding DNA- and hormone-binding domains were examined by single-strand conformation polymorphism analysis of polymerase chain reaction products using originally designed oligoprimers. Tissues from 7 cases of untreated stage B prostate cancer surgically removed and from 8 cases of endocrine therapy-resistant cancers obtained at autopsy were used in the study. Two different mutations were identified in exons D and H in the different cancer foci of the same cancer death patient. One mutation in exon D (at codon 701, Leu to His) was detected in the prostate, and the other in exon H (at codon 877, Thr to Ala) was found in metastatic tissues. In untreated cancer tissues and the other autopsy samples, no mutations were detected. The mutation in exon H was identical to that reported in LNCaP cells. These results indicate that AR gene mutations occur in relation to endocrine therapy-resistance, although the mutation was found in 1 out of 8 resistant cases (12.5%) at autopsy. 相似文献
998.
Summary On each lateral side of the cephalothorax segments, the adult Sinelobus stanfordi has a branchial chamber which contains an elongated bag-shaped gill and is covered by a thick branchiostegite. The ultrastructural study revealed that the inner surface of the branchiostegite is composed of a transporting-type epithelium which is morphologically distinct from the gill epithelium. Both epithelia are covered by extremely thin (about 80 nm) cuticle layers, suggesting high permeability to gases, ions, and water. In contrast, the outer surface of the branchiostegite consists of ordinary epithelium covered by a very thick cuticle layer in common with the body surface. The inner branchiostegal epithelium (4–10 m thick) has a shallow (about 1 m deep) apical infolding system of the cell membrane (AIS) and an extensive three-dimensional tubular network (about 120 nm in diameter) which is formed by the invagination of the basolateral cell membrane (TNB). The TNB is associated with slender mitochondria and occupies the majority of the cytoplasmic area of the epithelial cell. The gill epithelium, on the other hand, is about 10 m thick and characterized by an abundance of oval mitochondria, well-developed (4–5 m deep) AIS, and a smooth basal cell membrane lacking any infoldings. These morphological features indicate that not only the gill epithelia, but also the inner branchiostegal epithelia, are involved in the ion-transporting processes. The ultrastructural differences between these two kinds of epithelia also suggest their different roles in the osmoregulation of this animal, since it inhabits estuaries which are subject to extreme changes in salinity. 相似文献
999.
Shigeru Arimori Hideo Terada Kazuo Hayami Yoshitaka Aoyagi Shigeki Motomura Hitoshi Fukawa Noriko Akatsuka Susumu Shimizu Fumio Kodama Shozou Chiba Akio Urabe Mitsuhiro Omine Keiichi Harada 《Biotherapy》1993,6(2):149-153
Under the control of Kanagawa CML/HLBI phase IV study group in Japan, 18 cases out of registered 30 cases of chronic myelogeneous leukaemia consisting of 17 chronic phase and 1 accelerated phase, during July, 1991 to January, 1992, were analyzed for their hematological responses and cytogentic responses preliminarily. Hematological response rate (PR + CR) was 83.3% including 50.0% of CR, as judged by Kimura's criteria after treatment with HLBI alone (16 cases) or/and with other chemotherapy (2 cases). The dosage and duration of HLBI therapy required to get into the complete remission ranged from 212 to 1272 millions IU and between 6 to 42 weeks (mean value was 20 weeks), respectively. The clonally proliferated leukocytes and decreased physiological hematopoiesis started to recover from 2 to 4 weeks and reached their normal ranges from 16 weeks after 6 millions IU of HLBI were administered every day. In the 4 cases examined, 3 cases showed minimal cytogenetic responses and a case showed no cytogenetic response. Slight and temporary adverse effects were observed in 15 out of 18 cases (83.3%) including fever, general malaise, appetite loss, eruption, diarrhea, glossitis, hypogustation, weight loss and local muscle pain.Abbreviations HLBI
Human interferon alpha originated from human lymphoblastoid cell line 相似文献
1000.
Jiacong Chen Susumu Shimura Kohtaro Kirimura Shoji Usami 《Applied microbiology and biotechnology》1993,38(6):714-718
Lipase high-producing mutants with petroleum products as carbon sources were successfully induced from Trichosporon fermentans WU-C12 by ultraviolet (UV) light irradiation. In the first mutation step, one mutant strain, PU-30, derived from strain WU-C12 was selected. The productivity of extracellular lipase of PU-30 reached 58 units (U)/ml in the medium containing kerosene, being approximately twice the productivity of the parental strain WU-C12. In the second mutation step, the mutant strain 2PU-18 was induced from strain PU-30. In medium containing kerosene, gas oil and liquid paraffin, the 2PU-18 produced 70 U/ml, 62 U/ml and 60 U/ml of extracellular lipase, respectively. When various n-alkanes (C8-C18) were used as carbon sources, the parental strain WU-C12 produced more than 20 U/ml of lipase only from C9-C12 alkanes, but 2PU-18 could produce more than 50 U/ml of lipase from C8-C18 alkanes. When cultivated for 3 days in medium containing liquid paraffin, the activity ratios of extracellular lipase to total lipase and the values of extracellular lipase activity per dry-cell weight were 0.44 and 0.65 U/mg for WU-C12, and 0.62 and 1.82 U/mg for 2PU-18, respectively. These results indicate that the mutant strain 2PU-18 is superior in both total lipase productivity and permeability of lipase to the parental strain WU-C12 when petroleum products are used as carbon sources.
Correspondence to: S. Usami 相似文献