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951.
Kiguchi K Ishiwata I Ishiwata E Koshitaka Y Ohara T Okudai Y Sato S Kobayashi Y Ishizuka B Ishikawa H 《Human cell》2005,18(1):45-52
A cell line designated HTLS was established from the retroperitoneal liposarcoma. The HTLS line showed stable proliferation without interruption for 2 years and subcultivated over 35 times. The cells were elongated fibrous and spindle in shape, and neoplastic and pleomorphic features. The multinucleated giant cells with fine cytoplasm were seen. The cells proliferated slowly and the population doubling time was about 90 hours. The chromosome number showed a wide distribution of aneuploidy, the mode was hyperdiploid range (51-52), and many marker chromosomes were observed. The cells were transplantable into the submucosa of immunesuppressed hamster's cheek pouch and produced liposarcoma, while were not transplantable into subcutis of nude mice 相似文献
952.
Interspecies somatic cell nucleus transfer (iSCNT) could be a useful bioassay system for assessing the ability of mammalian somatic cells to develop into embryos. To examine this possibility, we performed canine iSCNT using porcine oocytes, allowed to mature in vitro, as recipients. Canine fibroblasts from the tail tips and dewclaws of a female poodle (Fp) and a male poodle (Mp) were used as donors. We demonstrated that the use of porcine oocytes induced blastocyst formation in the iSCNT embryos cultured in porcine zygote medium-3. In Fp and Mp, the rate of blastocyst formation from cleaved embryos (Fp: 6.3% vs. 22.4%; and Mp: 26.1% vs. 52.4%) and the number of cells at the blastocyst stage (Fp: 30.7 vs. 60.0; and Mp: 27.2 vs. 40.1) were higher in the embryos derived from dewclaw cells than in those derived from tail-tip cells (P < 0.05). The use of donor cells of any type in later passages decreased the rate of blastocyst formation. Treatment with trichostatin-A did not improve the rate of blastocyst formation from cleaved dewclaw cell-derived embryos but did so in the embryos derived from the tail-tip cells of Fp. Only blastocysts derived from dewclaw cells of Mp developed outgrowths. However, outgrowth formation was retrieved in the embryos derived from dewclaw cells of Fp by aggregation at the 4-cell stage. We inferred that iSCNT performed using porcine oocytes as recipients could represent a novel bioassay system for evaluating the developmental competence of canine somatic cells. 相似文献
953.
Sugawara H Kawano Y Hatakeyama T Yamaya T Kamiya N Sakakibara H 《Protein science : a publication of the Protein Society》2005,14(1):202-208
In higher plants, histidine-aspartate phosphorelays (two-component system) are involved in hormone signaling and stress responses. In these systems, histidine-containing phosphotransfer (HPt) proteins mediate the signal transmission from sensory histidine kinases to response regulators, including integration of several signaling pathways or branching into different pathways. We have determined the crystal structure of a maize HPt protein, ZmHP2, at 2.2 A resolution. ZmHP2 has six alpha-helices with a four-helix bundle at the C-terminus, a feature commonly found in HPt domains. In ZmHP2, almost all of the conserved residues among plant HPt proteins surround this histidine, probably forming the docking interface for the receiver domain of histidine kinase or the response regulator. Arg102 of ZmHP2 is conserved as a basic residue in plant HPt proteins. In bacteria, it is replaced by glutamine or glutamate that form a hydrogen bond to Ndelta atoms of the phospho-accepting histidine. It may play a key role in the complex formation of ZmHP2 with receiver domains. 相似文献
954.
Kazuyoshi Sugawara 《Primates; journal of primatology》1988,29(4):429-448
The male-female and male-male interactions of hybrid baboons betweenPapio anubis andP. hamadryas were analyzed quantitatively in two free-ranging groups in the Awash Valley, Ethiopia. Morphologically, one group (the Kerrayu
group) was closer to hamadryas, while the other (the Gorge group) was closer to anubis. The adult males were classified into
four categories; i.e., leaders of one-male units, males in pair units (both in the Kerrayu group), males with a closer appearance
to hamadryas, and males with an anubis-like appearance (both in the Gorge group). These categories coincided with the morphological
gradient from hamadryas to anubis. Social behavior was described in terms of 53 kinds of behavioral elements identified. In
both groups, the closer a male was to being hamadryas in morphology, the more frequent was the aggressive behavior it tended
to address toward partner females. The patterns of male-female interactions were compared between one-male units and pair
units in the Kerrayu group. In one-male units, females responded immediately with obedient behavior to the males' behavior
of directing visual attention toward them. In pair units, females responded with affinitive or avoiding behavior to physical
contact by males. The flow of male social behavior was resolved into transitions from one behavioral element to another, and
the succession rates for all the observed transitions were independently computed within each male category. By comparing
the principal pathways of the behavioral sequences between male categories, 31 “basic pathways” were identified, which were
presumed to be common to bothP. anubis andP. hamadryas. The basic pathways were composed of four main behavioral categories, i.e.,Contact, Visual-spacing, Aggressive behavior toward females, andAppeasing behavior toward males. In one-male units, transitions fromVisual-spacing toAggressive behavior were clearly recognized, whereas the principal pathways in pair units lacked such transitions. The frequency distributions
of behavioral elements among the above behavioral categories were compared among the four male categories. The more prevalent
anubis characters were in morphology, the larger was the proportion thatContact behavior occupied in the total amount of social behavior. The more prevalent hamadryas characters were, the larger was the
proportion thatVisual-spacing behavior occupied. The leaders of one-male units showed a higher percentage ofAggressive behavior than did males of the other three categories. A conspicuous difference was observed in the percentage ofAppeasing behavior between the Gorge and Kerrayu groups. It appeared that the high frequency ofAppeasing behavior among males in the Kerrayu group contributed to the spatial cohesion of this group. The similarities of morphology,
principal pathways, and frequency distribution of behavior were calculated for every combination of the four male categories.
The morphological similarities correlated best with the similarities of principal pathways. It is concluded that the sequential
structure of the male social behavior was strongly correlated with the genetic background, while the frequency of social behavior
itself was subject to factors other than innate behavioral tendencies, such as the characteristics of the social environment
and social context. 相似文献
955.
Masayoshi Kusama Hirohiko Sakuma Shirō Sugawara 《Bioscience, biotechnology, and biochemistry》2013,77(2):479-481
The pectate lyase I (PAL I) gene was cloned from Erwinia carotovora Er. The cloned DNA, 5.1 kb, seemed to contain the region necessary for the regulation of pectin lyase formation, as PAL I was induced by pectin in E. carotovora Er 18 containing the cloned PAL I gene. PAL I had a signal peptide of 22 amino acids which seemed to be cleaved between Gly and Ala. PAL I had a M.W. of 37,587 composed of 345 amino acids. The presence of promoter and SO sequences was suggested upstream of the translational start codon of the PAL I gene. A palindromic sequence, which might be important for the regulation of PAL I gene expression, was detected downstream from the putative promoter. Another open reading frame highly homologous to the PAL I gene was detected downstream from the PAL I gene and designated the PAL X gene. This gene had 81% homology in 606 bp from the translational start codon with the PAL I gene. 相似文献
956.
Effects of exercise training of 8 weeks and detraining on plasma levels of endothelium-derived factors, endothelin-1 and nitric oxide, in healthy young humans 总被引:15,自引:0,他引:15
Maeda S Miyauchi T Kakiyama T Sugawara J Iemitsu M Irukayama-Tomobe Y Murakami H Kumagai Y Kuno S Matsuda M 《Life sciences》2001,69(9):1005-1016
Vascular endothelial cells produce nitric oxide (NO), which is a potent vasodilator substance and has been proposed as having antiatherosclerotic property. Vascular endothelial cells also produce endothelin-1 (ET-1), which is a potent vasoconstrictor peptide and has potent proliferating activity on vascular smooth muscle cells. Therefore, ET-1 has been implicated in the progression of atheromatous vascular disease. Because exercise training has been reported to produce an alteration in the function of vascular endothelial cells in animals, we hypothesized that exercise training influences the production of NO and ET-1 in humans. The purpose of the present study was to examine whether chronic exercise could influence the plasma levels of NO (measured as the stable end product of NO, i.e., nitrite/nitrate [NOx]) and ET-1 in humans. Eight healthy young subjects (20.3 +/- 0.5 yr old) participated in the study and exercised by cycling on a leg ergometer (70% VO2max for 1 hour, 3-4 days/week) for 8 weeks. Venous plasma concentrations of NOx and ET-1 were measured before and after (immediately before the end of 8-week exercise training) the exercise training, and also after the 4th and 8th week after the cessation of training. The VO2max significantly increased after exercise training. After the exercise training, the plasma concentration of NOx significantly increased (30.69 +/- 3.20 vs. 48.64 +/- 8.16 micromol/L, p < 0.05), and the plasma concentration of ET-1 significantly decreased (1.65 +/- 0.14 vs. 1.23 +/- 0.12 pg/mL, p < 0.05). The increase in NOx level and the decrease in ET-1 level lasted to the 4th week after the cessation of exercise training and these levels (levels of NOx and ET-1) returned to the basal levels (the levels before the exercise training) in the 8th week after the cessation of exercise training. There was a significant negative correlation between plasma NOx concentration and plasma ET-1 concentration. The present study suggests that chronic exercise causes an increase in production of NO and a decrease in production of ET-1 in humans, which may produce beneficial effects (i.e., vasodilative and antiatherosclerotic) on the cardiovascular system. 相似文献
957.
Molecular phylogeny and taxonomic revision of the genus Wittrockiella (Pithophoraceae,Cladophorales), including the descriptions of W. australis sp. nov. and W. zosterae sp. nov. 下载免费PDF全文
Christian Boedeker Charles J. O'Kelly John A. West Takeaki Hanyuda Adele Neale Isamu Wakana Mike D. Wilcox Ulf Karsten Giuseppe C. Zuccarello 《Journal of phycology》2017,53(3):522-540
Wittrockiella is a small genus of filamentous green algae that occurs in habitats with reduced or fluctuating salinities. Many aspects of the basic biology of these algae are still unknown and the phylogenetic relationships within the genus have not been fully explored. We provide a phylogeny based on three ribosomal markers (ITS, LSU, and SSU rDNA) of the genus, including broad intraspecific sampling for W. lyallii and W. salina, recommendations for the use of existing names are made, and highlight aspects of their physiology and life cycle. Molecular data indicate that there are five species of Wittrockiella. Two new species, W. australis and W. zosterae, are described, both are endophytes. Although W. lyallii and W. salina can be identified morphologically, there are no diagnostic morphological characters to distinguish between W. amphibia, W. australis, and W. zosterae. A range of low molecular weight carbohydrates were analyzed but proved to not be taxonomically informative. The distribution range of W. salina is extended to the Northern Hemisphere as this species has been found in brackish lakes in Japan. Furthermore, it is shown that there are no grounds to recognize W. salina var. kraftii, which was described as an endemic variety from a freshwater habitat on Lord Howe Island, Australia. Culture experiments indicate that W. australis has a preference for growth in lower salinities over full seawater. For W. amphibia and W. zosterae, sexual reproduction is documented, and the split of these species is possibly attributable to polyploidization. 相似文献
958.
Isamu Shiio Kenji Ishii Kenzo Yokozeki 《Bioscience, biotechnology, and biochemistry》2013,77(9):1991-2000
The growth of Bacillus subtilis TR–44, a prototrophic transductant from one of inosine producers, was completely inhibited by 200 µg/ml of 5-fiuorotryptophan, a tryptophan analogue, and the inhibition was reversed by the addition of L-tryptophan.Several mutants resistant to 5FT* produced L-tryptophan in the growing cultures. The best producer, strain FT–39, which was selected on a medium containing 1500 µg/ml of 5FT, produced 2 g/liter of L-tryptophan, when cultured in a medium containing 8% of glucose but without any tryptophan precursors. In this mutant, anthranilate synthetase, a key enzyme of the tryptophan biosynthesis, had increased over 280-fold, presumably owing to a genetic derepression. From FT–39, mutants resistant to 7000 µg/ml of 5FT were derived. Among them, strain FF–25 produced 4 g/liter of L-tryptophan, twice as much as did the parental strain. Since this strain produced large amount of L-phenylalanine as well as L-tryptophan, the genetic alteration seemed to be involved in some metabolic regulation of common part of the aromatic amino acid biosynthetic pathway.Further, some auxotrophs derived from these 5FT resistant mutants produced more L-tryptophan than did the parental strains.Relationships between the accumulation of L-tryptophan and the regulation mechanisms of the L-tryptophan biosynthesis were discussed. 相似文献
959.
Repairing a double-strand break by homologous recombination requires binding of the strand exchange protein Rad51p to ssDNA, followed by synapsis with a homologous donor. Here we used chromatin immunoprecipitation to monitor the in vivo association of Saccharomyces cerevisiae Rad51p with both the cleaved MATa locus and the HML alpha donor. Localization of Rad51p to MAT precedes its association with HML, providing evidence of the time needed for the Rad51 filament to search the genome for a homologous sequence. Rad51p binding to ssDNA requires Rad52p. The absence of Rad55p delays Rad51p binding to ssDNA and prevents strand invasion and localization of Rad51p to HML alpha. Lack of Rad54p does not significantly impair Rad51p recruitment to MAT or its initial association with HML alpha; however, Rad54p is required at or before the initiation of DNA synthesis after synapsis has occurred at the 3' end of the invading strand. 相似文献
960.
Minamoto T Shimizu I 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2003,134(4):559-570
Amplified fragments encoding exon-4 of opsin cDNAs were cloned from the retina of landlocked ayu (Plecoglossus altivelis), and sequenced. On the basis of the sequence homology to previously characterized fish visual pigments, one clone was identified as rod opsin (AYU-Rh), and two clones as green (AYU-G1, -G2), one as red (AYU-R) and two as ultraviolet (AYU-UV1, -UV2) cone opsins. The 335-amino acid sequence deduced from the full-length cDNA of AYU-Rh included residues highly conserved in vertebrate rhodopsins and showed the greatest degree (88%) of similarity with salmon rhodopsin. Southern blotting analysis indicated that ayu possess two rhodopsin genes, one encoding visual rhodopsin (AYU-Rh) and the other non-visual extra-ocular rhodopsin (AYU-ExoRh). RT-PCR experiments revealed that AYU-Rh was expressed in the retina and AYU-ExoRh in the pineal gland. In situ hybridization experiments showed that the mRNA of AYU-Rh was localized only in rod cells not in cone cells. Lake and river type landlocked ayu having different amounts of retinal and 3-hydroxyretinal in their retinas expressed a rhodopsin (AYU-Rh) of identical amino acid sequence. 相似文献