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81.
Saishu YOSHIDA Masashi HIGUCHI Hiroki UEHARU Naoto NISHIMURA Mitsuyoshi TSUDA Hideji YAKO Mo CHEN Hideo MITSUISHI Yoshiya SANO Takako KATO Yukio KATO 《The Journal of reproduction and development》2014,60(4):295-303
The pituitary is an important endocrine tissue of the vertebrate that produces and secretes many hormones. Accumulating data
suggest that several types of cells compose the pituitary, and there is growing interest in elucidating the origin of these cell
types and their roles in pituitary organogenesis. Therein, the histogenous cell line is an extremely valuable experimental tool
for investigating the function of derived tissue. In this study, we compared gene expression profiles by microarray analysis and
real-time PCR for murine pituitary tumor-derived non-hormone-producing cell lines TtT/GF, Tpit/F1 and Tpit/E. Several genes are
characteristically expressed in each cell line: Abcg2, Nestin, Prrx1,
Prrx2, CD34, Eng, Cspg4 (Ng2),
S100β and nNos in TtT/GF; Cxcl12, Raldh1,
Msx1 and Twist1 in Tpit/F1; and Cxadr, Sox9,
Cdh1, EpCAM and Krt8 in Tpit/E. Ultimately, we came to the following conclusions: TtT/GF cells
show the most differentiated state, and may have some properties of the pituitary vascular endothelial cell and/or pericyte.
Tpit/F1 cells show the epithelial and mesenchymal phenotypes with stemness still in a transiting state. Tpit/E cells have a
phenotype of epithelial cells and are the most immature cells in the progression of differentiation or in the initial
endothelial-mesenchymal transition (EMT). Thus, these three cell lines must be useful model cell lines for investigating pituitary
stem/progenitor cells as well as organogenesis. 相似文献
82.
Kawahara Y Zinshteyn B Sethupathy P Iizasa H Hatzigeorgiou AG Nishikura K 《Science (New York, N.Y.)》2007,315(5815):1137-1140
83.
84.
Miyazawa M Tsukamoto T Anzai J Ishikawa Y 《Journal of agricultural and food chemistry》2004,52(14):4401-4405
Insecticidal activity of Angelica acutiloba extract and its constituents was investigated and compared with that of rotenone. Bioassay-guided isolation of the chloroform extract of A. acutiloba against larvae of Drosophila melanogaster afforded two phthalides, (Z)-butylidenephthalide (1) and (Z)-ligustilide (2), and two furanocoumarins, xanthotoxin (3) and isopimpinellin (4). The structures of these compounds were established by spectroscopic analysis. The isolated compounds 1, 2, 3, and 4 exhibited LC(50) values of 0.94, 2.54, 3.35, and 0.82 micromol/mL of diet concentration against larvae of D. melanogaster, respectively. Against both sexes (males/females, 1:1) of adults (5-7 days old), compound 1 showed the most potent activity with a LD(50) value of 0.84 microg/adult. Compound 1 is a more active insecticide than rotenone (LD(50) = 3.68 microg/adult) and has potential as a novel insect control agent. However, compound 2 was inactive against adults. The structure-activity relationship of phthalides isolated indicated that the aromaticity appeared to play an important role in the activity of both larvae and adults. To determine the insecticide mode of action for acute adulticidal activity, acetylcholinesterase (AChE) inhibitory activity was also investigated in vitro, and the result indicated that the acute adulticidal activity of compounds 3 and 4 was due to the inhibition of AChE. 相似文献
85.
Yukio?AgatsumaEmail author Yasuhiro?Kuwahara Kazuya?Taniguchi 《Fisheries Science》2005,71(5):1107-1114
ABSTRACT: The life cycle of Dilophus okamurae and the associated benthic invertebrate fauna were studied monthly or bimonthly from June 1998 to September 1999 at a depth of 4–7 m in Onagawa Bay along the Pacific coast of north-eastern Honshu, Japan (38°28'N, 149°29'E). Dry biomass ranged from 230 g/m2 in June to 10 g/m2 in October. Sporophytes with tetrasporangia appeared during July to September 1998. Gametophytes with oogonia or antheridia were observed for the first time in May 1999 during observation. The absence of mature sporophytes in 1999 suggests that the life cycle is completed over two years. The sympatric gastropods Lirularia iridescens , Homalopoma sangrarense, Conotalopia minima and Cantharidus callichroa synchronized with seasonal changes in biomass of this algae. In contrast, Barleeia angustata and B. trifasciata fluctuated independently. The juvenile sea urchin Strongylocentrotus nudus appeared in the algal population starting in October at 0.7 mm mean test diameter at high density, and disappeared after March. 相似文献
86.
H. KUDO Y. TSUNEYOSHI M. NAGAE S. ADACHI K. YAMAUCHI H. UEDA H. KAWAMURA 《Aquaculture Research》1994,25(Z2):171-181
Thyroid hormone regulates a number of physiological functions during smolting in salmonids. However, the target sites and roles of thyroid hormone in the central nervous system (CNS) are not known in detail. We detected thyroid hormone-specific binding sites (i.e. thyroid hormone receptors) in the olfactory epithelium and the brain (the olfactory bulb, the telencephalon, the mid-brain and the cerebellum) of wild masu salmon, Oncor- hynchus masou (Brevoort), during smolting by means of in vitro autoradiography with frozen sections. A saturation experiment with the brain indicated the presence of a single class of binding sites of high affinity. T3-specific binding was detected in the olfactory epithelium and in all regions of the brain except the olfactory bulb. The T3-specific binding value in the olfactory epithelium was higher than in all other regions of the brain. This binding value in the olfactory epithelium increased at the full-smolt stage. The presence of thyroid hormone receptors in various regions of the CNS suggests that thyroid hormone plays an important role in the functional change in the brain and the olfactory epithelium during smolting. 相似文献
87.
Two activable tracers, Rb and Eu, were injected into the sapwood of Japanese cedars (Cryptomeria japonica D. Don) to investigate the radial movement of minerals in their stems in the resting period. Eight trees of four cultivars,
two of which genetically form wet heartwood, were treated near the end of the growing period. At 40 days after the treatment,
Rb was detected in the outer heartwood, whereas Eu was not. Radial movement of Rb was more rapid in trees with wet heartwood
than in those with normal heartwood. At 204 days after the treatment, more Rb was detected in the heartwood than was found
on the first sampling, whereas no Eu was detected in the heartwood. The difference in radial movement between Rb and Eu was
considered mainly to be the result of selective transport of beneficial minerals by Japanese cedar. The difference in the
rate of radial movement of Rb between wet and normal heartwood became more conspicuous at 204 days after treatment. We concluded
that the movement of Rb from the sapwood to the outer heartwood was by active transport through the rays, whereas that in
the heartwood was by diffusion due to the gradient of Rb concentration. 相似文献
88.
89.
Kota Tsutsui Bum Hee Jeong Yukiko Ito Sang Woo Bang Yukio Kaneko 《Breeding Science》2011,61(4):373-379
Intergeneric hybridization was performed between Moricandia arvensis and four inbred lines of Brassica rapa following embryo rescue. Three F1 hybrid plants were developed from three cross combinations of M. arvensis × B. rapa, and amphidiploids were synthesized by colchicine treatment. Six BC1 plants were generated from a single cross combination of amphidipolid × B. rapa ‘Ko1-303’ through embryo rescue. One BC2 and three BC3 plants were obtained from successive backcrossing with B. rapa ‘Ko1-303’ employing embryo rescue. Alloplasmic and monosomic addition lines of B. rapa (Allo-MALs, 2n = 21) were obtained from backcrossed progeny of three BC3 plants (2n = 21, 22 and 23) without embryo rescue. An alloplasmic line of B. rapa (2n = 20) degenerated before floliation on 1/2 MS medium due to severe chlorosis. Allo-MALs of B. rapa (2n = 21) showed stable male sterility without any abnormal traits in vegetative growth and female fertility. Molecular analyses revealed that the same chromosome and cytoplasm of M. arvensis had been added to each Allo-MAL of B. rapa. This Allo-MAL of B. rapa may be useful material for producing cytoplasmic male sterile lines of B. rapa. 相似文献
90.
Mai Tsuda Ken-ichi Konagaya Ayako Okuzaki Yukio Kaneko Yutaka Tabei 《Breeding Science》2011,61(4):358-365
Imported genetically modified (GM) canola (Brassica napus) is approved by Japanese law. Some GM canola varieties have been found around importation sites, and there is public concern that these may have any harmful effects on related species such as reduction of wild relatives. Because B. juncea is distributed throughout Japan and is known to be high crossability with B. napus, it is assumed to be a recipient of B. napus. However, there are few reports for introgression of cross-combination in B. juncea × B. napus. To assess crossability, we artificially pollinated B. juncea with B. napus. After harvesting a large number of progeny seeds, we observed false hybrids and metaxenia of seed coats. Seed coat color was classified into four categories and false hybrids were confirmed by morphological characteristics and random amplified polymorphic DNA (RAPD) markers. Furthermore, the occurrence of false hybrids was affected by varietal differences in B. napus, whereas that of metaxenia was related to hybridity. Therefore, we suggest that metaxenia can be used as a marker for hybrid identification in B. juncea L. cv. Kikarashina × B. napus. Our results suggest that hybrid productivity in B. juncea × B. napus should not be evaluated by only seed productivity, crossability ought to be assessed the detection of true hybrids. 相似文献