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21.
T. Hamazaki A. Hirai T. Terano J. Sajiki S. Kondo T. Fujita Y. Tamura A. Kumagai 《Prostaglandins & other lipid mediators》1982,23(4):557-567
A highly purified ethyl ester of EPA (EPAEE) (74%) was manufactured from sardine oil. Sixty mg/kg/day of EPAEE was given orally to male Wishar rats for 8 weeks. No side effect or toxicity from the administration of EPAEE was observed. Plasma EPA concentration and the ratio of EPA to arachidonic acid were significantly increased, compared with control Wistar rats. An enhancement of PGI2-like substance production by aortas obtained from rats fed EPAEE was noted. Conversion of EPA to Λ17-6-keto-PGF1α, a stable metabolite of PGI3, could not be detected by an incubation study of 14C-EPA and aortas either from rats fed EPAEE or from control rats. Therefore, PGI2-like substance produced by rat aorta is most likely to be PGI2. itself and not PGI3. 相似文献
22.
Hiroaki Matsui Takeshi Kato† Chosabro Yamamoto Keisuke Fujita ‡ Toshiharu Nagatsu† 《Journal of neurochemistry》1981,37(2):289-296
Abstract: This paper describes a new, sensitive assay for dopamine-β-hydroxylase (DBH) activity in human cerebrospinal fluid (CSF), serum and brain tissues by high performance liquid chromatography (HPLC) with electrochemical detection (ED). Dopamine (DA) was used as a substrate and was incubated under optimal conditions. Norepinephrine (NE) formed enzymatically from DA was isolated by a double-column procedure, the first column of Dowex-50-H+ and the second column of aluminum oxide. NE was adsorbed on the second aluminum oxide column and then eluted with 0.5 M-hydrochloric acid and assayed by HPLC-ED. Epinephrine (EN) was added to each incubation mixture as an internal standard, and this assay was therefore highly reproducible. The peak height in HPLC was linear from 500 fmol to 100 pmol of NE and EN. The lower limit of detection for NE formed enzymatically was about 30 pmol, which indicated that the sensitivity of this procedure was comparable to that of radioassay procedures. We applied the method to measurement of the activity of and examination of some of the characteristics of DBH in human CSF. DBH activity in CSF of Parkinsonian patients was lower than that of control patients. The properties of DBH in human CSF were similar to those in serum and adrenal medulla. 相似文献
23.
Loc Van Nguyen Ryoji Takahashi Stephen Mwangi Githiri Tito O. Rodriguez Nobuko Tsutsumi Sayuri Kajihara Takasi Sayama Masao Ishimoto Kyuya Harada Keisuke Suematsu Tomomi Abiko Toshihiro Mochizuki 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(4):743-755
Key message
Greatest potential, QTLs for hypoxia and waterlogging tolerance in soybean roots were detected using a new phenotypic evaluation method.Abstract
Waterlogging is a major environmental stress limiting soybean yield in wet parts of the world. Root development is an important indicator of hypoxia tolerance in soybean. However, little is known about the genetic control of root development under hypoxia. This study was conducted to identify quantitative trait loci (QTLs) responsible for root development under hypoxia. Recombinant inbred lines (RILs) developed from a cross between a hypoxia-sensitive cultivar, Tachinagaha, and a tolerant landrace, Iyodaizu, were used. Seedlings were subjected to hypoxia, and root development was evaluated with the value change in root traits between after and before treatments. We found 230 polymorphic markers spanning 2519.2 cM distributed on all 20 chromosomes (Chrs.). Using these, we found 11 QTLs for root length (RL), root length development (RLD), root surface area (RSA), root surface area development (RSAD), root diameter (RD), and change in average root diameter (CARD) on Chrs. 11, 12, 13 and 14, and 7 QTLs for hypoxia tolerance of these root traits. These included QTLs for RLD and RSAD between markers Satt052 and Satt302 on Chr. 12, which are important markers of hypoxia tolerance in soybean; those QTLs were stable between 2 years. To validate the QTLs, we developed a near-isogenic line with the QTL region derived from Iyodaizu. The line performed well under both hypoxia and waterlogging, suggesting that the region contains one or more genes with large effects on root development. These findings may be useful for fine mapping and positional cloning of gene responsible for root development under hypoxia.24.
The freshwater type of ninespine sticklebacks, genus Pungitius, is widely distributed in northern Japan and reproductively isolated from other genetically divergent types endemic to small
regions in Japan. This type expresses dimorphism in its lateral plate morphology: complete and partial row morphs. The two
morphs show a parapatric distribution in Japan. To clarify the process involving the distribution of these two morphs, we
examined their phylogeography based on restriction fragment length polymorphism of an entire mitochondrial DNA (mtDNA). The
survey was carried out with seven restriction enzymes on the populations of the freshwater type collected from 41 localities
across the distribution range in Japan, and 6 further Pungitius populations from the Okhotsk Sea coast of Russia were appended. An unweighted pair-group method with arithmetic averages
(UPGMA) tree among 54 mtDNA haplotypes resolved eight clustering groups that differed in sequence divergence by approximately
1.3%–2.1%. Two of the eight groups were found only in Russia. mtDNA phylogenies constructed by neighbor-joining and Wagner
parsimony methods suggested that the haplotypes of each plate morph were polyphyletic. The geographic distribution pattern
of these groups suggests that they should be classified into two broad categories, one with extensive distribution and the
other with localized distribution of the constituent haplotypes within a group. The former groups were found mainly in the
populations with the completely plated morph and the latter groups with the partially plated morph. It is supposed that twice
dispersals of dimorphic or complete plated ancestors and genetic differentiation during the interglacial played an important
role in the formation of the present distribution of the two morphs in Japan.
Received: March 28, 2000 / Revised: November 3, 2000 / Accepted: January 16, 2001 相似文献
25.
Human recombinant stem cell factor promotes spermatogonial proliferation,but not meiosis initiation in organ culture of newt testis fragments 总被引:3,自引:0,他引:3
Abé K Jin Y Yamamoto T Abé S 《Biochemical and biophysical research communications》2002,294(3):695-699
We previously showed that mammalian FSH stimulates the proliferation of newt spermatogonia and induces their differentiation into primary spermatocytes in vitro. In the current study, to examine a possibility that stem cell factor (SCF) is involved in the proliferation of newt spermatogonia and/or their differentiation into primary spermatocytes, human recombinant SCF (rhSCF) was added to organ culture of testicular fragments. rhSCF was found to stimulate the spermatogonial proliferation and the spermatogonia progressed to the seventh generation that is the penultimate stage before primary spermatocyte stage. However, the spermatogonia did not differentiate into primary spermatocytes, but instead died of apoptosis. These results indicate that rhSCF promotes the proliferation of newt spermatogonia, but not the initiation of meiosis. 相似文献
26.
Keisuke Okada Hiroyuki Abe Fumio Ike Yoshitoshi Ogura Tetsuya Hayashi Aya Fukui-Miyazaki Keiji Nakamura Naoaki Shinzawa Yasuhiko Horiguchi 《PloS one》2015,10(2)
Bordetella bronchiseptica is a pathogenic bacterium causing respiratory infections in a broad range of mammals. Recently, we determined the whole genome sequence of B. bronchiseptica S798 strain isolated from a pig infected with atrophic rhinitis and found four single-nucleotide polymorphisms (SNPs) at positions -129, -72, +22, and +38 in the region upstream of dnt encoding dermonecrotic toxin (DNT), when compared with a rabbit isolate, RB50. DNT is known to be involved in turbinate atrophy observed in atrophic rhinitis. Immunoblotting, quantitative real-time PCR, and β-galactosidase reporter assay revealed that these SNPs resulted in the increased promoter activity of dnt and conferred the increased ability to produce DNT on the bacteria. Similar or identical SNPs were also found in other pig isolates kept in our laboratory, all of which produce a larger amount of DNT than RB50. Our analysis revealed that substitution of at least two of the four bases, at positions -72 and +22, influenced the promoter activity for dnt. These results imply that these SNPs are involved in the pathogenicity of bordetellae specific to pig diseases. 相似文献
27.
Genetic variations in humans associated with differences in the course of hepatitis C 总被引:6,自引:0,他引:6
Saito T Ji G Shinzawa H Okumoto K Hattori E Adachi T Takeda T Sugahara K Ito JI Watanabe H Saito K Togashi H Ishii K Matsuura T Inageda K Muramatsu M Kawata S 《Biochemical and biophysical research communications》2004,317(2):335-341
The outcome of hepatitis C virus (HCV) infection varies among individuals, but the genetic factors involved remain unknown. We conducted a population-based association study in which 238 Japanese individuals positive for anti-HCV antibody were genotyped for 269 single nucleotide polymorphisms (SNPs) in 103 candidate genes that might influence the course of infection. Altogether, 50 SNPs in 32 genes were listed. Genetic polymorphisms in IL4, IL8RB, IL10RA, PRL, ADA, NFKB1, GRAP2, CABIN1, IFNAR2, IFI27, IFI41, TNFRSF1A, ALDOB, AP1B1, SULT2B1, EGF, EGFR, TGFB1, LTBP2, and CD4 were associated with persistent viremia (P < 0.05), whereas those in IL1B, IL1RL1, IL2RB, IL12RB1, IL18R1, STAT5A, GRAP2, CABIN1, IFNAR1, Mx1, BMP8, FGL1, LTBP2, CD34, and CD80 were associated with different serum alanine aminotransferase levels in HCV carriers (P < 0.05). The sorted genes allow us to draw novel hypotheses for future studies of HCV infection to ultimately identify bona fide genes and their variations. 相似文献
28.
The Role of Half-Transporters in Multidrug Resistance 总被引:13,自引:0,他引:13
Susan E. Bates Robert Robey Keisuke Miyake Koneti Rao Douglas D. Ross Thomas Litman 《Journal of bioenergetics and biomembranes》2001,33(6):503-511
ATP-binding cassette proteins comprise a superfamily of transporter proteins, a subset of which have been implicated in multidrug resistance. Although P-glycoprotein was described over 15 years ago, the recent expansion in the number of transporters identified has prompted renewed interest in the role of drug transporters in clinical drug resistance. These newly identified transporters include additional members of the MRP family, ABC2, and a new half-transporter, MXR/BCRP/ABCP1. This half-transporter confers high levels of resistance to mitoxantrone, anthracyclines, and the camptothecins SN-38 and topotecan. At 72 kDa, MXR localizes to the plasma membrane in cells which highly overexpress the protein either through gene amplification or though gene rearrangement. Future studies will be aimed at identifying an inhibitor, and attempting to translate recognition of this new transporter into a target for anticancer treatment. 相似文献
29.
Ren Shimamoto Naoki Amano Tomoko Ichisaka Akira Watanabe Shinya Yamanaka Keisuke Okita 《PloS one》2014,9(4)
It has been shown that DNA demethylation plays a pivotal role in the generation of induced pluripotent stem (iPS) cells. However, the underlying mechanism of this action is still unclear. Previous reports indicated that activation-induced cytidine deaminase (Aid, also known as Aicda) is involved in DNA demethylation in several developmental processes, as well as cell fusion-mediated reprogramming. Based on these reports, we hypothesized that Aid may be involved in the DNA demethylation that occurs during the generation of iPS cells. In this study, we examined the function of Aid in iPS cell generation using Aid knockout (Aid−/−) mice expressing a GFP reporter under the control of a pluripotent stem cell marker, Nanog. By introducing Oct3/4, Sox2, Klf4 and c-Myc, Nanog-GFP-positive iPS cells could be generated from the fibroblasts and primary B cells of Aid−/− mice. Their induction efficiency was similar to that of wild-type (Aid+/+) iPS cells. The Aid−/− iPS cells showed normal proliferation and gave rise to chimeras, indicating their capacity for self-renewal and pluripotency. A comprehensive DNA methylation analysis showed only a few differences between Aid+/+ and Aid−/− iPS cells. These data suggest that Aid does not have crucial functions in DNA demethylation during iPS cell generation. 相似文献
30.
Yamada T Suzuki A Ueda H Ueda Y Miyauchi K Endo G 《Applied microbiology and biotechnology》2008,81(4):771-781
Comparative analyses of bacterial community successions in the composting materials were done for a conventional windrow post-treatment
(WPOT) process with the hyperthermophilic pre-treatment (HTPRT) and simple windrow composting (SWC; without the HTPRT). Multidimensional
scaling profiles based on data of terminal restriction fragment length polymorphisms of the bacterial population in the samples
of every 7 days composting material and analyses of the 16S rRNA gene-based clone library of the 7 and 21 days composting
materials suggested that bacterial communities of the composting materials differed much between these two processes until
the 35 days of composting, whereas that they were closely related to each other at the final composting stage (42 days of
composting). Detailed phylogenetic analysis clarified that all WPOT clone libraries contained many clones of the lineages
of aerobic bacteria (for example, bacilli). However, the most abundant clones retrieved from all SWC materials were affiliated
with a clone cluster closely related to identified and classified members of the phylum Firmicutes that have strictly anaerobic metabolism pathways. From these results, we conclude that the HTPRT process contributed to easily
establish an aerobic ecosystem from the early stage to the final stage of WPOT composting with plowing the materials only
once a week. 相似文献