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81.
Social isolation stress augments angiogenesis induced by colon 26-L5 carcinoma cells in mice 总被引:3,自引:0,他引:3
Wu W Murata J Murakami K Yamaura T Hayashi K Saiki I 《Clinical & experimental metastasis》2000,18(1):1-10
We have previously shown that tumor necrosis factor-α (TNF-α), which is an important angiogenesis-related factor, was over-secreted in male BALB/c mice under social isolation stress as compared with the control, and closely associated with a remarkable elevation of tumor invasion and metastasis of colon 26-L5 carcinoma cells. In the present study, we explored the effect of isolation stress on the angiogenesis caused by colon 26-L5 carcinoma cells in vivo and in vitro. Social isolation lead to the enhancement of tumor growth after intrahepatic implantation with a fragment of colon 26-L5 tumor. Angiogenic response (number of vessels oriented towards tumor mass) and tumor growth (size) were significantly increased in the socially isolated mouse relative to that in the group-housed mice. Furthermore, higher protein level of hepatic TNF-α was found in the stressed mice than that in the control. Expression of mRNA for vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were also elevated in the tumor regions and liver tissues of the stressed mice in comparison with that in group-housed mice. On the other hand, hepatic sinusoidal endothelial (HSE) cells treated with TNF-α exhibited a marked promotion of the migration, invasion, expression of mRNA for matrix metalloproteinase (MMP)-9, and tube-like formation, but no cytotoxicity against the cells in vitro. The above data suggest that the social isolation stress augmented the tumor-induced angiogenesis probably by up-regulating the angiogenesis-related factors, including TNF-α, VEGF and HGF, and consequently mediating the functions of endothelial cells such as migration, invasion, and tube-like formation. 相似文献
82.
Molecular cloning and complete nucleotide sequence of the genome of Japanese encephalitis virus Beijing-1 strain 总被引:5,自引:0,他引:5
Hiroshi Hashimoto Akio Nomoto Koji Watanabe Takayuki Mori Toshiyuki Takezawa Chikara Aizawa Tsutomu Takegami Keiichi Hiramatsu 《Virus genes》1988,1(3):305-317
The genomic RNA of the Japanese encephalitis virus (JEV) Beijing-1 strain was reversely transcribed and the synthesized cDNA was molecularly cloned. Six continuous cDNA clones that cover the entire virus genome were established and sequenced to determine the complete nucleotide sequence of the JEV RNA. The precise genomic size was estimated as 10,965 bases long. With flanking 95 bases at the 5 and 583 bases at the 3 non-coding regions, one long open reading frame (ORF) was revealed encoding a virus polyprotein with 3,429 amino acid residues. Because of sequence homologies observed between JEV and other flaviviruses, the genome organization of JEV appears to be identical with other flaviviruses. Genetic variation detected among flavivirus genomes is consistent with the established serological relatedness between JEV and other members of flaviviruses. The secondary structure of the JEV genome is deduced and discussed concerning its involvement in genome replication. 相似文献
83.
Yukio Nishimoto Tsukasa Iwahashi Toru Nishihara Hiroyuki Katayama Koichi Kueibayashi Toshihiko Takao Koji Saito 《Pathology international》1987,37(1):155-166
An autopsy case of hepatitis associated aplastic anemia was presented. A 58-year-old Japanese female with non-A, non-B hepatitis was admitted on August 2, 1983. Moderate grade of fever and hemorrhagic diathesis appeared on September 16, when hepatitis was evaluated as being under resolving. The peripheral blood and bone marrow findings were consistent with aplastic anemia. Since infection was suggested by increased levels of serum gamma-globulin and CRP, treatment with antibiotics as well as prednisolone and blood transfusion was initiated. Since September 21, gradual tenderness and edema on the right lower abdominal wall appeared. She died on October 3.
On postmortem examination, systemic plasmacytosis with lymphadenopathy and septic monilial infection was revealed. Numerous plasma cells were atypical, but were immunohistochemically proved to be polyclonal. The bone marrow showed a massive and diffuse plasma cell proliferation with extremely scarce myeloid cells and megakaryocytes. There was a large granulomatous lesion with monilial infection in the wall of the ileocecum. By these findings, systemic plasmacytosis was suspected to be due to chronic monilial infection.
The pathogenesis of systemic plasmacytosis in aplastic anemias and in other diseases were discussed with relation to the present case. 相似文献
On postmortem examination, systemic plasmacytosis with lymphadenopathy and septic monilial infection was revealed. Numerous plasma cells were atypical, but were immunohistochemically proved to be polyclonal. The bone marrow showed a massive and diffuse plasma cell proliferation with extremely scarce myeloid cells and megakaryocytes. There was a large granulomatous lesion with monilial infection in the wall of the ileocecum. By these findings, systemic plasmacytosis was suspected to be due to chronic monilial infection.
The pathogenesis of systemic plasmacytosis in aplastic anemias and in other diseases were discussed with relation to the present case. 相似文献
84.
Kawano Y Nakamura S Fukuda J Sugano T Takai N Miyakawa I 《Growth factors (Chur, Switzerland)》2005,23(2):169-175
Our objective was to clarify the physiological role of vascular endothelial growth factor (VEGF) by amnion-derived (WISH) cells. WISH cells were cultured, and the effect of epidermal growth factor (EGF), mitogen-activated protein (MAP) kinase kinase or extracellular signal-regulated kinase (ERK) kinase (MEK) inhibitors (U0126) or phosphatidylinositol (PI) 3-kinase on the production of VEGF was examined. VEGF was assayed by ELISA. The activation of MAP kinase and akt, which is phosphorylated by PI 3-kinase, were detected by Western blot analysis using anti-phosphorylated MAP kinase antibody and anti-phosphorylated akt antibody. In the time course of VEGF production following EGF treatment, VEGF production showed a significant increase only after 16 (p < 0.01)-32h (p < 0.01). EGF increased the production of VEGF by WISH cells in a dose-dependent manner. The MAP kinase and akt activity were determined by treatment with EGF. VEGF production was significantly decreased following pretreatment with U0126 or wortmannin for two hours before treatment with EGF (p < 0.01, p < 0.01). WISH cells appeared to produce VEGF via a mechanism involving tyrosine kinase activation of EGF receptor and MAP kinase or PI 3-kinase. It is suggested that VEGF may contribute to the neovascularization and proliferation of the placenta and gestational tissue, and EGF may play an important role in regulation of VEGF production in the placenta. 相似文献
85.
Accumulation of filamentous tau in the cerebral cortex of human tau R406W transgenic mice 总被引:4,自引:0,他引:4
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Ikeda M Shoji M Kawarai T Kawarabayashi T Matsubara E Murakami T Sasaki A Tomidokoro Y Ikarashi Y Kuribara H Ishiguro K Hasegawa M Yen SH Chishti MA Harigaya Y Abe K Okamoto K St George-Hyslop P Westaway D 《The American journal of pathology》2005,166(2):521-531
Missense mutations of the tau gene cause autosomal dominant frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17), an illness characterized by progressive personality changes, dementia, and parkinsonism. There is prominent frontotemporal lobe atrophy of the brain accompanied by abundant tau accumulation with neurofibrillary tangles and neuronal cell loss. Using a hamster prion protein gene expression vector, we generated several independent lines of transgenic (Tg) mice expressing the longest form of the human four-repeat tau with the R406W mutation associated with FTDP-17. The TgTauR406W 21807 line showed tau accumulation beginning in the hippocampus and amygdala at 6 months of age, which subsequently spread to the cortices and subcortical areas. The accumulated tau was phosphorylated, ubiquitinated, conformationally changed, argyrophilic, and sarcosyl-insoluble. Activation of GSK-3beta and astrocytic induction of mouse tau were observed. Astrogliosis and microgliosis correlated with prominent tau accumulation. Electron microscopic examination revealed the presence of straight filaments. Behavioral tests showed motor disturbances and progressive acquired memory loss between 10 to 12 months of age. These findings suggested that TgTauR406W mice would be a useful model in the study of frontotemporal dementia and other tauopathies such as Alzheimer's disease (AD). 相似文献
86.
Nakata H Inui K Wasaka T Tamura Y Kida T Kakigi R 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,162(3):293-299
The present study investigated the characteristics of the middle-latency negative potential of event-related potentials (ERPs) using somatosensory go/nogo tasks. We manipulated interstimulus interval (ISI) in Experiment 1 and stimulus probability in Experiment 2 and analyzed the subtracted difference waveform resulting from subtraction of the ERP evoked by the go stimulation from that evoked by the nogo stimulation. In Experiment 1, the peak latency of negativity became significantly longer as the ISI increased, but the peak amplitude was unchanged. The reaction time (RT) was longer with increasing ISI. In Experiment 2, manipulation of the stimulus probability yielded an increase in peak amplitude with decreasing probability of the nogo stimulus, but did not affect the latency. The RT increased as the probability of a nogo stimulus rose. Because manipulation of the ISI and stimulus probability elicited different brain activities, we hypothesized that manipulation of the ISI elicited a delay of the stimulus evaluation process including response inhibition, and that stimulus probability significantly affected the strength of the response inhibition process. 相似文献
87.
Hiroki Kurahashi Kenzo Akagi Ikuo Yana Thomas Melot Olivier Delattre Gilles Thomas Shintaro Okada Shin-ichiro Takai Isamu Nishisho 《Journal of human genetics》1994,39(2):243-248
Summary Eight cosmid clones were regionally assigned to small subregions of chromosome 22 by hybridization with a total of 22 somatic cell hybrids. One cosmid was localized to the proximal part of 22q which contained the region commonly deleted in the DiGeorge syndrome. Seven cosmids showing restriction fragment length polymorphisms were localized to the telomeric region distal to the MB locus, which was reported to be frequently deleted in sporadic meningioma. These cosmids, when finely mapped and ordered, are considered useful for the identification of genetic alterations on this chromosome arm. 相似文献
88.
Medaka fish (Oryzias latipes) were exposed to various doses of X-rays or fast neutrons, and the frequency of micronucleated cells (MNCs) was measured in gills sampled at 12- or 24-hr intervals from 12 to 96 hr after exposure. The resulting time course of MNC frequency was biphasic, with a clear peak 24 hr after exposure, irrespective of the kind of radiation applied and the dose used. The half-life of MNCs induced in the gill tissues by the two exposures fluctuated around 28 hr, with no significant dose-dependent trend for either X-ray- or neutron-exposed fish. As assayed 24 hr after exposure, the MNC frequency increased linearly over the control level with increasing doses of both X-rays and fast neutrons. The relative biological effectiveness (RBE) of fast neutrons to X-rays for MNC induction was estimated to be 4.3 +/- 0.6. This value is close to the RBE value of 5.1 +/- 0.3 reported for fast neutron induction of somatic crossing-over mutations in Drosophila melanogaster that arise from recombination repair of DNA double-strand breaks. These results and other data support our conclusion that the medaka gill cell micronucleus assay is a reliable short-term test for detecting potential inducers of DNA double-strand breaks. 相似文献
89.
Nakamura H Kawakami A Yamasaki S Nakashima T Kamachi M Migita K Kawabe Y Nakamura T Koji T Hayashi Y Eguchi K 《Laboratory investigation; a journal of technical methods and pathology》2000,80(9):1421-1427
Apoptotic cell death in acinar and ductal epithelial cells is thought to play an important role in the development of salivary gland dysfunction in patients with Sjogren's syndrome (SS). We examined the expression of anti-apoptotic molecules in salivary glands from patients with SS. The labial salivary glands from six human T-cell leukemia virus (HTLV)-I-seronegative and eleven HTLV-I-seropositive SS patients were analyzed by immunohistochemistry. In vitro experiments were performed with a human salivary gland cell line (HSG cells). Immunohistologic analyses revealed that Bcl-2 and Bcl-x were preferentially expressed in salivary infiltrating mononuclear cells more than acinar and ductal epithelial cells. In contrast, strong X chromosome-linked inhibitor of apoptosis protein (XIAP) expression was evident in both acinar and ductal epithelial cells. The pattern of expression of these anti-apoptotic molecules was similar in both HTLV-I-seropositive and HTLV-I -seronegative SS patients. Western blot analysis confirmed expression of XIAP in cultured HSG cells. The expression of XIAP in HSG cells was increased by IL-1beta, TGF-beta1, or IL-10. However, XIAP expression was down-regulated by TNF-alpha, which induced apoptotic cell death of HSG cells with an increase in caspase-3 activity. These effects of TNF-alpha in HSG cells were antagonized by IL-1beta, TGF-beta1, or IL-10. Our results suggest that XIAP is important in regulating apoptotic cell death of acinar and ductal epithelial cells in patients with SS. 相似文献
90.
Kenichiro Karasawa Nobuo Sugiura Yusuke Hori Sakaru Suzuki Junichi Onaya Katsukiyo Sakurai Koji Kimata 《Clinical & experimental metastasis》1997,15(2):83-93
Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis. 相似文献