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11.
12.
Yamato Kikkawa Kotaro Akaogi Hiroto Mizushima Naoki Yamanaka Makoto Umeda Kaoru Miyazaki 《In vitro cellular & developmental biology. Animal》1996,32(1):46-52
Summary Ladsin is a laminin-like cell-adhesive scatter factor with potent cell motility-stimulating ability and was purified from
serum-free conditioned medium of a malignant human gastric adenocarcinoma cell line STKM-1. To test its possible role in tumor
angiogenesis, we investigated its effect on primary culture of endothelial cells (human umbilical vein endothelial cells)
and endothelial cell line ECV304 in this study. Cell adhesion and motility effects of ladsin were observed in both types of
endothelial cells. In cell-attachment assay, ladsin interacted with integrin α3β1 that was expressed on the endothelial cell
surface. In Boyden chambers, ladsin stimulated both directed and random migration of ECV304 cells. Ladsin induced repair of
artificial wounds generated in ECV304 cell monolayers by stimulating cell migration. Ladsin did not affect the growth rate
of ECV304 cells at a low cell density but significantly increased the saturation cell density. These results suggest that
ladsin may be involved in the adhesion and migration of endothelial cells under some physiological and pathological conditions. 相似文献
13.
N. Ohmiya Shinsuke Saga Masaharu Ohbayashi Ken-ichi Kozaki Osamu Miyaishi Miya Kobayashi Shiro Kasuya Tomiyasu Arisawa Hidemi Goto Tetsuo Hayakawa 《Histochemistry and cell biology》1997,108(1):27-34
An association between eosinophils and tissue damage has been observed in numerous disorders. However, few reports have addressed
the role of infiltrating eosinophils in gastric ulcer healing. The aim of this study was to investigate the kinetics and role
of eosinophils infiltrating experimental chronic gastric ulcers in the rat. We developed a monoclonal antibody against human
matrix metalloproteinase 1 (MMP1) purified from conditioned culture medium of human skin fibroblasts. Acetic acid-induced
gastric ulcers were resected from rats on days 1, 3, 5, 10, 20, 40, and 180 after the days of induction (day 0). Tissue specimens
were immunostained with this antibody and examined with an electron microscope. Few eosinophils were observed in the granulation
tissue until day 20. By days 40 and 180, MMP1-positive eosinophils had increased in the granulation tissue of open ulcers.
Azan staining revealed dispersed collagen fibers around infiltrating eosinophils. In contrast, scars demonstrated few eosinophils
in fibrous tissue on days 40 and 180. Eosinophils which express MMP1 infiltrate granulation tissue at the chronic stage of
gastric ulceration. The results suggest that eosinophils may play a role in tissue remodeling and deterioration of ulceration.
Accepted: 18 March 1997 相似文献
14.
Rika Morishita Shinsuke Saga Noriko Kawamura †Yoshio Hashizume ‡Toshiaki Inagaki Kanefusa Kato Tomiko Asano 《Journal of neurochemistry》1997,68(2):820-827
Abstract: The localization of two forms of the γ subunit of G proteins, γ3 and γ12, was examined in the mammalian brain. Concentrations of these two γ subunits increased markedly, as did those of glial fibrillary acidic protein, during postnatal development in the rat cerebral cortex. In aged human brains, by contrast, the concentration of γ3 tended to decrease with age, whereas that of γ12 in the temporal cortex increased slightly. An immunohistochemical study of human brains revealed that γ3 was abundant in the neuropil, whereas γ12 was localized in glial cells. In the hippocampal formation of aged human brains, levels of γ12-positive cells, as well as levels of glial fibrillary acidic protein- and vimentin-positive astrocytes, increased, in particular in the CA1 subfield and the prosubiculum, in which there was a decrease in the number of pyramidal cells. The appearance of γ12-positive cells associated with the loss of pyramidal cells was also observed in the hippocampus of rats that had been treated with kainic acid. These results indicate that γ12 is strongly expressed in reactive astrocytes. In a study of cultured neural cells, we found that γ12 was predominant in glioma cells, such as C6 and GA-1 cells, in contrast with the specific localization of γ3 in PC12 pheochromocytoma cells, which are neuron-like cells. Taken together, the results indicate that γ3 and γ12 are selectively expressed in neuronal and glial cells, respectively, and that concentrations of γ3 and γ12 in the brain are related to the numbers and/or extent of maturation of these cells. 相似文献
15.
Phytochrome Control of Its Own Synthesis in Pisum sativum 总被引:1,自引:0,他引:1
Otto Veit; Sch?fer Eberhard; Nagatani Akira; Yamamoto Kotaro T.; Furuya Masaki 《Plant & cell physiology》1984,25(8):1579-1584
An analysis of phytochrome synthesis in Pisum seedlings by measuringthe activity of polysomal polyadenylated RNA (poly-A+-RNA) codingfor phytochrome apoprotein showed phytochrome control of itsown synthesis; brief red-light irradiation of pea seedlingsinhibited the activity of the RNA, and the red-light effectwas red/far-red reversible.
4 Permanent address: Biology Department, Faculty of Science,University of Tokyo, Hongo, Tokyo 113, Japan. (Received August 13, 1984; Accepted September 17, 1984) 相似文献
16.
Summary Methacholine (MCh)-induced changes in intracellular concentrations of Na, K, and Cl ([Na]i, [K]i, and [Cl]i, respectively) and in cellular dry mass (a measure of cell shrinkage) were examined in isolated monkey eccrine sweat secretory coils by electron probe X-ray microanalysis using the peripheral standard method. To further confirm the occurrence of cell shrinkage during MCh stimulation, the change in cell volume of dissociated clear and dark cells were directly determined under a light microscope equipped with differential interference contrast (DIC) optics. X-ray microanalysis revealed a biphasic increase in cellular dry mass in clear cells during continuous MCh stimulation; an initial increase of dry mass to 158% (of control) followed by a plateau at 140%, which correspond to the decrease in cell volume of 37 and 29%, respectively. The latter agrees with the MCh-induced cell shrinkage of 29% in dissociated clear cells. The MCh-induced increase in dry mass in myoepithelial cells was less than half that of clear cells. During the steady state of MCh stimulation, both [K]i and [Cl]i of clear cells decreased by about 45%, whereas [Na]i increased in such a way as to maintain the sum of [Na]i+[K]i constant. There was a small (12–15mm) increse in [Na]i and a decrease in [K]i in myoepithelial cells during stimulation with MCh. Dissociated dark cells failed to significantly shrink during MCh stimulation. The decrease in [Cl]i in the face of constant [Na]i+[K]i suggests the accumulation of unknown anion(s) inside the clear cell during MCh stimulation. While the decrease in [K]i and [Cl]i may be instrumental in facilitating influx of ions via Na–K–2Cl cotransporters, the functional significance of MCh-induced cell shrinkage remains unknown. 相似文献
17.
We studied the localization of the epidermal growth factor (EGF) in eccrine and apocrine sweat glands with light microscopic and electron microscopic immunohistochemistry. Anti-human EGF (anti-hEGF) polyclonal antiserum and anti-hEGF monoclonal antibody (MAb) were used for the study. Light microscopic immunohistochemistry with monoclonal and polyclonal antibodies showed that hEGF-like immunoreactivity was strongly positive in the myoepithelial cells and weakly positive in the secretory cells of eccrine sweat glands. In apocrine sweat glands, it was strongly positive in the secretory cells as well as in the myoepithelial cells. Immunoelectron microscopy with polyclonal antibody showed that hEGF-like immunoreactivity was present in secretory granules of apocrine secretory cells. These granules had mitochondrion-like internal structure. No reactivity was observed on the eccrine secretory cells by immunoelectron microscopy. Neither dark cell granules nor mitochondria in eccrine secretory cells were labeled with anti-hEGF antibody. In both eccrine and apocrine sweat glands, hEGF-like immunoreactivity was diffusely present in the cytoplasm of myoepithelial cells. However, nuclei and mitochondria of myoepithelial cells were devoid of immunoreactivity for hEGF. Our observations indicate that apocrine sweat glands may secrete more hEGF in the sweat than eccrine sweat glands. 相似文献
18.
cDNA Cloning of Indole-3-Acetic Acid-Regulated Genes: Aux22 and SAUR from Mung Bean (Vigna radiata) Hypocotyl Tissue 总被引:3,自引:0,他引:3
Five cDNAs of auxin-regulated genes were isolated from mungbean (Vigna radiata) hypocotyl sections by differential hybridizationscreening. They were related to the soybean genes, Aux22 [Ainleyet al. (1988) J. Biol. Chem. 263: 10658] and SAUR [McClure etal. (1989) Plant Cell 1: 229]. Regulation of expression of thesegenes, examined by Northern blot analysis, appeared similarto that reported in soybean hypocotyls. (Received August 10, 1991; Accepted October 14, 1991) 相似文献
19.
Joël M. Durant Kotaro Ono Nils Chr. Stenseth
ystein Langangen 《Global Change Biology》2020,26(10):5554-5563
Climate change has profound ecological effects, yet our understanding of how trophic interactions among species are affected by climate change is still patchy. The sympatric Atlantic haddock and cod are co‐occurring across the North Atlantic. They compete for food at younger stages and thereafter the former is preyed by the latter. Climate change might affect the interaction and coexistence of these two species. Particularly, the increase in sea temperature (ST) has been shown to affect distribution, population growth and trophic interactions in marine systems. We used 33‐year long time series of haddock and cod abundances estimates from two data sources (acoustic and trawl survey) to analyse the dynamic effect of climate on the coexistence of these two sympatric species in the Arcto‐Boreal Barents Sea. Using a Bayesian state‐space threshold model, we demonstrated that long‐term climate variation, as expressed by changes of ST, affected species demography through different influences on density‐independent processes. The interaction between cod and haddock has shifted in the last two decades due to an increase in ST, altering the equilibrium abundances and the dynamics of the system. During warm years (ST over ca. 4°C), the increase in the cod abundance negatively affected haddock abundance while it did not during cold years. This change in interactions therefore changed the equilibrium population size with a higher population size during warm years. Our analyses show that long‐term climate change in the Arcto‐Boreal system can generate differences in the equilibrium conditions of species assemblages. 相似文献
20.
Chisato Yoshida Atsushi B. Tsuji Hitomi Sudo Aya Sugyo Tatsuya Kikuchi Mitsuru Koizumi Yasushi Arano Tsuneo Saga 《PloS one》2013,8(3)
Small cell lung cancer (SCLC) is an aggressive tumor and prognosis remains poor. Therefore, the development of more effective therapy is needed. We previously reported that high levels of an anti-c-kit antibody (12A8) accumulated in SCLC xenografts. In the present study, we evaluated the efficacy of two antibodies (12A8 and 67A2) for radioimmunotherapy (RIT) of an SCLC mouse model by labeling with the 90Y isotope.