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151.
152.
Makoto Suematsu Shigenari Houzawa Soichiro Miura Hiroshi Nagata Tetsuji Kitahora Tetsuo Morishita Chikara Oshio Masaharu Tsuchiya 《Luminescence》1989,4(1):531-534
Reaction difference of oxyradical generation and luminol-dependent photoemission of zymosan- and phorbol ester-treated neutrophils were investigated using a conventional photomultiplier and ultrasensitive photonic imaging technique. Zymosan-treated cells released a concentrated photonic burst corresponding to the cellular distribution. In contrast, phorbol ester-treated cells produced a negligible level of photoemission, and the additional application of Ca2+ ionophore enhanced the photonic burst, which was gradually spread out into extracellular space. Serine protease inhibitors did not attenuate PMA-induced chemiluminescence but did attenuate zymosan-induced chemiluminescence. This suggests the involvement of serine protease in the respiratory burst of phagocytizing neutrophils. 相似文献
153.
Photoisomerization mechanism of rhodopsin and 9-cis-rhodopsin revealed by x-ray crystallography 下载免费PDF全文
The primary photochemical process of the visual function has been investigated using the three crystallographic models, 11-cis-rhodopsin, all-trans-bathorhodopsin, and the artificial isomeric 9-cis-rhodopsin. Detailed examination of the atomic displacements and dihedral angle changes of the retinal chromophore involved in the interconversion among these isomers suggests the mechanism of isomerization efficiency. 相似文献
154.
Summary Processes in the development of intestinal metaplasia of the stomach were investigated from the morphological and histochemical approaches using light and electron microscopic techniques. The specimens taken from 38 gastric carcinomas and 15 gastric and/or duodenal ulcers were subjected to this study. Morphological appearances of the intestinal metaplasia observed in routine examination with hematoxylin and eosin staining was able to be divided into complete and incomplete metaplasia by the light and electron microscopic histochemical stainings of the mucosubstances. The columnar cells at the area of the incomplete metaplasia had both the properties of the intestinal epithelia and the gastric foveolar epithelia. The incomplete as well as the complete metaplasia arose from the generative cells at the isthmus of the gland. The generative cells, however, sometimes gradually transformed to produce the complete metaplastic cells. The two processes of the development of the intestinal metaplasia were proposed and discussed. 相似文献
155.
Miho Furue Tetsuji Okamoto Hiroyuki Hayashi J. Denry Sato Makoto Asashima Shigeru Saito 《In vitro cellular & developmental biology. Animal》1999,35(3):131-135
Summary To study the mechanisms of morphogenesis in salivary gland regeneration, we have established the RSMG-1 cell line derived
from submandibular gland (SMG) of 10-wk-old Wistar female rats in serum-free culture. Our finding that RSMG-1 cells originated
from duct cells was based on morphology and immunohistochemical results. In three-dimensional serum-free collagen gel culture,
HGF induced branching morphogenesis of RSMG-1 cells. Histological examination revealed that HGF-induced branching structure
exhibited well-formed lumina. This morphology closely resembles that found in vivo. The cells also expressed activin A. Exogenously
added activin A at a high concentration reduced HGF-induced branching morphogenesis. These findings suggest that the morphogenesis
of the salivary gland is modulated by HGF and activin A. Our results show that the RSMG-1 cell line may be useful in studies
of salivary gland regeneration. 相似文献
156.
Asaumi H Watanabe S Taguchi M Tashiro M Otsuki M 《American journal of physiology. Gastrointestinal and liver physiology》2007,293(5):G972-G978
Local tissue pressure is higher in chronic pancreatitis than in the normal pancreas. We reported recently that pressure application induces synthesis of extracellular matrix (ECM) and cytokines in pancreatic stellate cells (PSCs) and that epigallocatechin gallate (EGCG), a potent antioxidant, inhibits the transformation of PSCs from quiescent to activated phenotype and ethanol-induced synthesis of ECM and cytokines in PSCs. These results suggest that oxidative stress and reactive oxygen species (ROS) are important in PSC activation. The aim of this study was to clarify the effects of ROS on activation and functions of pressure-stimulated PSCs. We used freshly isolated rat PSCs and culture-activated PSCs. Pressure was applied on rat cultured PSCs by adding compressed helium gas into a pressure-loading apparatus. PSCs were cultured with or without antioxidants (EGCG and N-acetyl cysteine) under normal or elevated pressure. Externally applied high pressure (80 mmHg) resulted in a gradual decrease of superoxide dismutase activity in PSCs and increased intracellular ROS generation as early as 30 s, reaching a peak level at 1 h. Antioxidants significantly inhibited ROS generation. Pressure increased the expression levels of alpha-smooth muscle actin, alpha(1)(I)-procollagen, and TGF-beta1 in PSCs. EGCG suppressed these alterations, abolished pressure-induced phosphorylation of p38 MAPK, and suppressed pressure-induced PSC transformation to activated phenotype. Our results indicated that ROS is a key player in pressure-induced PSC activation and ECM synthesis. Antioxidants could be potentially effective against the development of pancreatic fibrosis in patients with chronic pancreatitis. 相似文献
157.
Xue Bin Zheng Misao Tsubokura Yongkun Wang Chun Xie Tetsuji Nagano Kazuhiko Someya Tomoko Kiyohara Kiyomi Suzuki Takeshi Sanekata 《Microbiology and immunology》1995,39(10):821-824
Thirty strains of Yersinia pseudotuberculosis were isolated from rabbits (17 strains), wild rats (9 strains) and house rats (4 strains) in China between 1990 and 1993. The biochemical properties of these isolates were identical with those of Y. pseudotuberculosis and no special characteristics were found in these strains. Serologically, serogroups 4b and 5b were identical to isolates found in Japan, and a new serogroup 1c and unclassified strains have also been detected. The existence of virulence-associated properties were different among strains. The pYV plasmid was detected from 6 strains of 30 isolates. This report documents the presence of Y. pseudotuberculosis in China, providing important epidemiological information. 相似文献
158.
Spatial variations in xylem sap flux density in evergreen oak trees with radial-porous wood: comparisons with anatomical observations 总被引:1,自引:0,他引:1
Makiko Tateishi Tomo’omi Kumagai Yasuhiro Utsumi Toshihiro Umebayashi Yasuki Shiiba Kazunobu Inoue Kiyohiro Kaji Keiichiro Cho Kyoichi Otsuki 《Trees - Structure and Function》2008,22(1):23-30
To estimate whole-tree water use when employing sap flow measurements, integration of the sap flux density (F
d) over the sapwood area is needed. Accordingly, it is necessary to obtain information on the characteristics of stem water
transportation such as spatial variations in F
d and the active xylem area in the stem cross-section. Although evergreen oak trees with radial-porous wood represent a major
component of secondary forests in western Japan, detailed information on their stem water transportation characteristics remains
unclear. In the present study, we used the heat dissipation method (Granier method) to conduct measurements of azimuthal and
radial variations in the F
d of Quercus glauca Thunb. ex Murray, a representative evergreen broad-leaved tree in western Japan. Further, by analyzing the anatomy of the
xylem structure, we examined why F
d varies spatially in the stem cross-section. By using a dye solution injected into a radial hole bored into the tree trunk,
we confirmed that the entire stem is hydroactive. We also compared the spatial variations in F
d and water conductivity per xylem area (K
s) which were estimated by using the observed vessel diameters and their density over the stem cross-section and Hagen–Poiseuille’s
law. Azimuthal and radial variations in F
d reached about 60 and 50% of the maximum values, respectively, and could be explained by spatial variation in K
s. As a result, we obtained statistical parameters describing the spatial variation in F
d in Q. glauca and determined that whole-tree water use estimated from measurements in one direction had at most ±20% potential errors for
studied trees. 相似文献
159.
Sun L Tamaki H Ishimaru T Teruya T Ohta Y Katsuyama N Chinen I 《Bioscience, biotechnology, and biochemistry》2004,68(12):2613-2615
Seven-week old female rats fed restricted foods including the fish oils Docosahesaenoic Acid (DHA) and Eicosapentaenoic Acid (EPA) and perilla oil with food intake decreased by 50%, had increases of fracture force and bone mineral density (BMD) and decreases in levels of Deoxypiridinoline (Dpd) and Calcium (Ca) in the urine, compared with those of rats with osteoporosis due to restricted soy bean oil food intake. Therefore, the fish oils DHA and EPA and perilla oil depressed excretion of urinary Ca and inhibited osteoporosis due to restricted food intake. 相似文献
160.
Yoshiko Myoken Yoshinari Myoken Tetsuji Okamoto Mikio Kan J. Denry Sato Kazuaki Takada 《In vitro cellular & developmental biology. Animal》1994,30(11):790-795
Summary A squamous cell carcinoma cell line Nakata proliferated in serum-free culture and was not responsive to exogenous fibroblast
growth factor-1 (FGF-1). Immunostaining revealed that Nakata cells expressed FGF-1 in their cytoplasms and nuclei. Two molecular
mass species of FGF-1 (16 and 18 kDa) were identified in cell extracts by Western blot. These cells also expressed high-affinity
FGF-1 binding sites (Kd=360 pM, 28 000 sites/cell). The results of cross-linking with [125I]FGF-1 demonstrated the presence of two bands with molecular masses of 160 and 140 kDa. The addition of FGF-1 specific antisense
oligonucleotides at 25 μM to Nakata cells resulted in an 82% inhibition in cell growth and suppressed FGF-1 expression. This effect was dose-dependent
and specific, because sense oligonucleotides were ineffective in inhibiting cell growth. In addition, Nakata cell growth was
suppressed by an anti-FGF-1 neutralizing antibody, which resulted in a 52% inhibition at 8 μg/ml. These results demonstrate
that Nakata cells produce FGF-1, and indicate that this growth factor acts in an autocrine manner by interacting with FGF-1
binding sites on Nakata cells. 相似文献