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71.
Zenjiro Osawa Tsubura Morota Kenichi Hatanaka Toshihiro Akaike Kei Matsuzaki Hideki Nakashima Naoki Yamamoto Eiichiro Suzuki Hiroshi Miyano Tohru Mimura Yutaro Kaneko 《Carbohydrate polymers》1993,21(4):283-288
Sulfopropyl curdlan was synthesized, its structure was determined, and the anti-HIV activity was compared with that of standard curdlan sulfates obtained with piperidine N-sulfonic acid in dimethyl sulfoxide. It was shown that sulfopropyl curdlan exhibits weaker anti-HIV activity than curdlan sulfate. Curdlan sulfates were synthesized with a SO3-pyridine complex in a heterogeneous phase. It was shown from 13C-NMR spectra of acetylated curdlan sulfates that they had a different substituent distribution from standard curdlan sulfate. The cytotoxicity of the curdlan sulfates was attributed to their heterogeneous structure. 相似文献
72.
Serum-free culture of rat keratinocytes 总被引:2,自引:0,他引:2
Hirosuke Oku Chikara Kumamoto Tomoyuki Miyagi Takanori Hiyane Junichi Nagata Isao Chinen 《In vitro cellular & developmental biology. Animal》1994,30(8):496-503
Summary Procedures for the serum-free culture of rat keratinocytes have been established. Basal cells prepared from epidermis of newborn
rat were stored in liquid nitrogen and used for primary culture. Among the available media, MCDB 153, developed originally
for human keratinocyte (HK) culture, was the best for the development of serum-free formulation. To grow rat keratinocytes,
bovine serum albumin was arbitrarily substituted for the macromolecule supplements needed for HK culture, i.e. fetal bovine
serum protein or bovine pituitary extract. Qualitative and quantitative adjustment of supplements was thereafter made to support
rapid cell growth. Satisfactory cell growth was achieved in the optimized medium of MCDB 153 supplemented with growth factors
and amino acids: insulin (10 μg/ml), hydrocortisone (0.1 μg/ml), epidermal growth factor (25 ng/ml), calcium chloride (0.2
mM), histidine (0.23 mM), isoleucine (0.05 mM), tryptophane (0.015 mM), threonine (1.25 mM), tyrosine (0.031 mM), alanine (4.08 mM), and albumin (2 mg/ml). This optimized culture system was superior to the original HK culture condition for rapid growth
of rat keratinocytes. Under our condition, cells grew as a monolayer, becoming confluent, but without stratification, and
were passaged 2 to 3 times without any changes in morphology. The serum-free formulation allows us to control more accurately
the concentrations of biomolecules in the medium including lipids and hormones, and therefore will be suitable for the study
focusing on lipid metabolism or hormonal regulation of rat keratinocytes. 相似文献
73.
Kazuyoshi Masuda Shunji Nagata Koichiro Hirano Yasushi Takagishi Hidematsu Hirai 《Microbiology and immunology》1993,37(2):165-167
This paper describes an attempt to effectively induce antibody-dependent cell-mediated cytotoxicity (ADCC) in nude mice. A monoclonal antibody against α-fetoprotein, 80G, coadministered with spleen cells from other nude mice bearing HuH-7N (xenograft of human hepatoma cell line, HuH-7) significantly suppressed the growth of HuH-7N as compared to treatment with 80G alone. 80G with spleen cells from normal nude mice also had some suppressive effect. In contrast, no effect was observed with each spleen cells alone as well as 80G alone. These results suggest that further supply of effector cells could enhance ADCC activity in nude mice. 相似文献
74.
Batdorj Enkhjin AlOgayil Najla Zhuang Qinwei Kim-wee Galvez Jose Hector Bauermeister Klara Nagata Kei Kimura Tohru Ward Monika A. Taketo Teruko Bourque Guillaume Naumova Anna K. 《Mammalian genome》2023,34(1):44-55
Mammalian Genome - Several lines of evidence suggest that the presence of the Y chromosome influences DNA methylation of autosomal loci. To better understand the impact of the Y chromosome on... 相似文献
75.
76.
Hisashi Nagata 《Ecological Research》1993,8(1):1-9
The breeding sites of Styan's grasshopper warblers are restricted to small islands and distributed discretely. The study on
the marked population was conducted on two islets, Okitsu-jima and Ohtsukue-jima, located near Fukuoka, Japan, from 1981 to
1989. About 20 and 70 birds bred on the two islets, respectively, and the mean density of breeding pairs was 25.5 ha−1. The dispersal pattern and population, structure were examined. Adult birds returned to the same breeding site. Males always
reoccupied the same territory as in previous years but females not. Males were more philopatric and only female yearlings
dispersed over long distances and moved between the breeding sites in Hakata Bay. The returning rate was 0.57 for adults,
and 0.21 for juveniles. The age distribution of birds at Ohtsukue-jima was almost stable, while that at Okitsu-jima was unstable
because it was a marginal habitat for the birds. Estimating from the dispersal pattern and age structure of this warbler the
population near Fukuoka consists of only four islets and is almost stable. 相似文献
77.
Kazuyoshi Masuda Shunji Nagata Koichiro Hirano Yasushi Takagishi Hidematsu Hirai 《生物化学与生物物理学报:疾病的分子基础》1993,1182(2):128-132
This study was carried out to clarify the reason for elevation of serum α-fetoprotein (AFP) level of nude mice bearing hepatoma cells after treatment with monoclonal antibodies (MoAbs) to AFP. MoAbs to AFP showed no effect on the cumulative amounts of AFP secreted from human hepatoma cell line, HuH-7, in vitro. However, the treatment of nude mice bearing HuH-7N cells (HuH-7 xenograft) with MoAbs to AFP led to elevation of the serum AFP level in spite of the fact that the growth curve of HuH-7N cells was similar to that for PBS treatment. This apparent elevation of the serum AFP level is thought to be due to the slow elimination of AFP-MoAb immune complexes with little lattice structure from circulation, but not the enhancement of AFP secretion of HuH-7N cells. Thus, when using a MoAb alone or MoAb-drug conjugate, the serum AFP level should only be cautiously used as a tumor marker for evaluating the targeting immunotherapy. 相似文献
78.
79.
Podocytes outgrown from isolated glomeruli in vitro have failed to express fully differentiated in vivo phenotypes. In an
attempt to determine whether podocytes in metanephric culture accomplish terminal differentiation, as observed in vivo, we
investigated expression of their characteristic phenotypic features in rat metanephric organ cultures using immunohistochemistry
and electron microscopy. Rat metanephroi were harvested on embryonic day 12.5 and cultured on transmembrane filters for 9
days. Morphological examination revealed two maturation stages when the podocytes resembled those of the S-shaped body stage
and maturational stages of glomeruli in vivo. Electron microscopy revealed that, firstly podocytes lost their intercellular
contacts and, simultaneously, the tight junctions shifted into close proximity to cell bases, followed by foot process development.
Immunohistochemistry demonstrated that the tight junction protein, ZO-1, and specific podocytic markers, pp44, 5-1–6, podocalyxin
and vimentin were expressed in a cell maturity-dependent manner, as observed in newborn rat kidneys. Furthermore, glomerular
basement membrane components, collagen type IV and laminin, were expressed in the glomerular center. Our findings that cell
maturity-dependent expression of structural and functional phenotypes in podocytes in metanephric culture was the same as
that observed in developing kidneys in vivo indicate that podocyte differentiation during glomerulogenesis may be operated
by an intrinsic property, such as programmed cell fate. Furthermore, these highly differentiated podocytes in vitro may provide
clues that will help to establish a podocyte culture system.
Accepted: 26 February 1997 相似文献
80.
Ultrastructural localization of glycogen in the granulocytes of normal rabbit bone marrow. 总被引:1,自引:0,他引:1
The glycogen of rabbit granulocytes has been studied in glutaraldehyde and osmium tetroxide fixed bone marrow by the periodic acid-thiocarbohydrazide-silver proteinate procedure (PA-TCH-SP). The PA-TCH-SP procedure involved the staining of intracytoplasmic glycogen more densely than the routine lead citrate staining. The PA-TCH-SP procedure demonstrated the intracytoplasmic glycogen in all three kinds of granulocytes. Though a sequence of intensity was observed in each stage of cell maturation, intracytoplasmic glycogen increased generally in accordance with cell maturation in the granulocytes. Functional significance of the glycogen in the granulocytes was discussed in relation to its staining. A very weak reaction in the granules of the granulocytes was described in relation to their contents. 相似文献