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11.
Yoshimura R Matsuyama M Hase T Tsuchida K Kuratsukuri K Kawahito Y Sano H Segawa Y Nakatani T 《International journal of molecular medicine》2003,12(6):861-865
Peroxisome proliferator activator-receptor (PPAR)-gamma ligand induces growth arrest of cancer cells through apoptosis. In this study, we examined the effects of PPAR-gamma inhibitors on cell proliferation in renal cell carcinoma (RCC), bladder tumor (BT), and prostatic carcinoma (PC) cell lines. We investigated the inhibitory effect of PPAR-gamma ligands, troglitazone and 15-deoxy-Delta12,14-prostaglandin J2 (15dPGJ2) on RCC, BT and PC-derived cell lines using MTT assay and Hoechst staining. PPAR-gamma ligands (troglitazone and 15dPGJ2) induced the reduction of cell viability with the half-maximal concentration of growth inhibition of RCC, BT, and PC cell lines. Furthermore, counting cells at days 1, 2 and 3, clearly showed marked inhibition of cell proliferation using troglitazone and 15dPGJ2. All PPAR-gamma inhibitors stopped the growth of all RCC, BT and PC cells. Cells treated with PPAR-gamma inhibitors showed chromatin condensation, cellular shrinkage, small membrane-bound bodies (apoptotic bodies), and cytoplasmic condensation. These cellular changes were typically redundant characteristics of apoptosis. PPAR-gamma ligands may mediate potent antiproliferative effects against RCC, BT and PC cells through differentiation. Thus, PPAR-gamma may become a new target in treatment of urological tumors. 相似文献
12.
Taro Okada Akira Yasoshima Koji Uetsuka Hiroyuki Nakayama Kunio Doi 《Experimental and toxicologic pathology》2003,55(2-3):147-152
Ultrastructual characteristics of the dorsal skin responses to a single irradiation of UVA (1100 kJ/m2) were examined in Wistar-derived hypotichotic WBN/ILA-Ht rats (HtRs). In the epidermis, mitochondrial swelling of some keratinocytes and dissociation of keratinocytes due to intercellular edema developed at 3 hours (h) after irradiation and continued to 48 h. At 6 h, in addition to these changes, necrosis of keratinocytes accompanied with infiltration of neutrophils was also observed in some portions, and epidermal hyperplasia with many keratinocytes showing nucleolar hypertrophy and some mitotic keratinocytes was observed at 48 h. In the dermis, mitochondrial swelling and/or partial cytoplasmic destruction in capillary endothelial cells and edema with inflammatory cell infiltration were observed at and after 3 h, and extravasation of erythrocytes was found in some capillaries at 48 h. Mitochondrial swelling was also frequently found in pericytes and fibroblasts. Inflammatory cells were mainly composed of neutrophils throughout the experimental period. Mild degranulation of mast cells which also showed mitochondrial swelling was observed at and after 3 h, and a close special relationship between mast cells and fibroblasts or neutrophils was sometimes observed. In conclusion, the most prominent change in the dorsal skin of HtRs exposed to UVA was degeneration of capillary endothelial cells, resulting in edema and inflammatory cell infiltration, and the most characteristic cytopathic effect of UVA was mitochondrial swelling, and it was common to keratinocytes, capillary endothelial cells, pericytes, mast cells, and fibroblasts. 相似文献
13.
Tateishi T Nakamura M Ueda M Himeno S Yamashita T Yamauchi T Nishi K Mori K Asonuma K Inomata Y Ando Y 《Rinsho byori. The Japanese journal of clinical pathology》2005,53(9):825-831
Recently nutrition support team (NST) has been established for the purpose of prevention of complications which are caused by nutrition disorders and reduction of the medical expenses. Although physical examinations and blood biochemical data had been used as the indexes evaluating nutritional of patients, they were not suitable for the evaluation for the short-term in-patient. On the contrary, serum albumin (ALB) has been wildly used as a nutritional marker. However, it is impossible to evaluate nutrition state for the short-term in-patient and acute phase disease patient accurately, because the plasma half-life is 21 days and it takes long time to detect the change in nutritional state by its value. Rapid turnover proteins (RTP), whose plasma half-life is shorter, has paid attention to evaluate nutritional state for the short-term in-patients and acute phase disease patients. Although, prognostic inflammatory and nutritional index (PINI) was considered as a useful maker for evaluating inflammatory and nutritional states using the concentrations of transthyretin (TTR), a RTP, alpha1-acid glycoprotein (alpha1-AG), a chronic inflammation marker, C reactive protein (CRP), a acute inflammation marker, and ALB, However, it has several pitfalls. We newly made serum amyloid A (SAA) index using SAA instead of CRP. When we compared SAA index with PINI in many diseases, it turned out that SAA index became a more effective index which reflected the patient condition than did PINI. As for this index, it is expected to be used by NST while further alternation may be needed. 相似文献
14.
Kenichi Wakasa Masami Sakurai Morito Monden Tsuyoshi Yamada Chikazumi Kuroda Taro Marukawa Jun Okamura 《Pathology international》1988,38(10):1363-1367
We describe a case of hepatocellular carcinoma in which a tumor embolus in the portal vein and 3 of 4 intrahepatic metastases were necrosed completely by Lipiodol transcatheter chemo-embolization (Lipiodol-TCE). Tumor emboli in the portal vein and intrahepatic metastases usually cannot be necrosed by conventional transcatheter chemo-embolization alone, because small nodules such as intrahepatic metastases and tumor emboli in the portal vein are supplied blood from the portal vein. However, in this case, Lipiodol-TCE was effective against tumor emboli in the portal vein and intrahepatic metastases. ACTA PATHOL JPN 38: 1363-1367, 1988. 相似文献
15.
Fumiyuki Yamasaki Yoshinori Kajiwara Seiji Hama Taro Murakami Toshikazu Hidaka Taiichi Saito Hiroyuki Yoshioka Kazuhiko Sugiyama Kazunori Arita Kaoru Kurisu 《Pathobiology》2007,74(1):22-31
OBJECTIVE: To investigate the mechanism of staurosporine-induced glioma cell death and cell cycle arrest using adenovirus-mediated gene transfection, as well as the function of retinoblastoma (Rb) and genetic instability induced by staurosporine. METHODS: Cell cycle regulation, cell death and nuclear abnormalities induced by staurosporine were examined using an adenovirus vector expressing Rb, p16 or p21 genes in human glioma cell lines. RESULTS: The Rb-defective SF-539 cell line was resistant to staurosporine compared with cell lines expressing intact Rb. SF-539 glioma cells exposed to staurosporine became multinucleated and then died. Multinucleation was prevented in SF-539 cells transfected with the Rb gene, thus decreasing the death rate of these cells. CONCLUSIONS: These results imply that enforced Rb expression protects cells from genomic instability induced by staurosporine regardless of its upstream molecular effects. 相似文献
16.
Exponential hyperbolic sine function fitting of heart rate response to constant load exercise 总被引:1,自引:0,他引:1
Mizuo J Nakatsu T Murakami T Kusachi S Tominaga Y Mashima K Uesugi T Ueda H Suezawa C Tsuji T 《The Japanese journal of physiology》2000,50(4):405-412
We attempted to fit heart rate (HR) changes induced by constant exercise loads of different intensities to an exponential hyperbolic sine curve by the least-squares method, and we compared the results with the fitting of the changes to exponential curves. Seven healthy male volunteers performed three different intensities of constant-load exercise on a bicycle ergometer. The exponential hyperbolic sine function adequately fitted the HR responses induced by all three different intensities of loads: low (30 W: correlation coefficient, r = 0.68 +/- 0.13, mean +/- SD), moderate (75 W: r = 0.93 +/- 0.07) and high (125 W: r = 0.97 +/- 0.02). The first-order exponential curve fitted only the moderate load response. Although the second-order exponential equation fitted the HR response for both the moderate and high loads, the equation did not fit the low-load response (r = 0.43 +/- 0.26). In low-load exercise, the sum of the power of the residuals for the exponential hyperbolic sine curve fitting was significantly smaller than that for the first- or second-order exponential curve fitting. In conclusion, the exponential hyperbolic sine function is useful for quantitative analyses of the HR response to exercise loads of various intensities. 相似文献
17.
Oda Y Funasaka K Kitano M Nakama A Yoshikura T 《Environmental and molecular mutagenesis》2004,43(1):10-19
In the present study, we developed a rapid umu-microplate test system that uses the nitroreductase- and O-acetyltransferase-overproducing Salmonella typhimurium strain NM3009 and the O-acetyltransferase-overproducing S. typhimurium strain NM2009 to detect genotoxic activity in small volume samples. The assay was used to test the genotoxicity of several standard mutagens and environmental samples. Exponentially growing cultures of NM3009, NM2009, and the parental strain TA1535/pSK1002 were incubated in 96-well microplates with test chemicals both in the presence and in the absence of rat liver S9. The relative beta-galactosidase activities were then determined colorimetrically using either chlorophenol red-beta-D-galactopyranoside (CPRG) or O-nitrophenyl-beta-D-galactopyranoside (ONPG) as a measure of umuC gene induction activity. The sensitivities of NM3009 without S9 mix and NM2009 with S9 mix to nitroarenes and aromatic amines were up to 24- to 75-fold higher than those of the parent strain. Induction of umuC gene expression was detected more readily with CPRG than ONPG. The umu-microplate assay also detected genotoxicity in organic extracts of particulate matter from air samples collected in Osaka City, Japan. The pattern of the responses suggested that the genotoxic activity of the particulate extract was due primarily to nitrated polycyclic aromatic hydrocarbons. Our results indicate that the umu-microplate assay may be a useful way of carrying out rapid screens for genotoxicity in small-volume environmental samples. 相似文献
18.
Evidence of the monoclonal composition of human endometrial epithelial glands and mosaic pattern of clonal distribution in luminal epithelium 总被引:8,自引:0,他引:8
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Tanaka M Kyo S Kanaya T Yatabe N Nakamura M Maida Y Okabe M Inoue M 《The American journal of pathology》2003,163(1):295-301
The endometrium is a highly regenerative tissue that plays a crucial role in implantation. We examined the clonal constitution of glandular cells as well as the luminal epithelium of this unique tissue. Using collagenase-based digestion techniques with microscopic manipulation, we isolated individual human endometrial glands and examined their clonality using a polymerase chain reaction-based assay for nonrandom X chromosome inactivation with an X-linked androgen receptor gene. Most of the glands analyzed were composed of monoclonal populations of epithelial cells and one of the glands exhibited a loss of heterogeneity in the androgen receptor gene. In addition, adjacent glands within a 1-mm(2) area shared clonality, suggesting that clonality of the luminal epithelium is regionally defined. The clonality of endometrium was further confirmed in a study of female mice that harbor the green fluorescent protein gene on either the maternal or paternal X chromosome. Fluorescent microscopy of uterine sections revealed that individual endometrial glands consisted completely of either fluorescent or nonfluorescent cells and that the surface epithelium exhibited a clear boundary between these cell types. These findings suggest that single or multiple stem cells with uniform clonality exist on the bottom of each endometrial gland and genetic alterations occurring in such cells may play a critical role in endometrial carcinogenesis. The possible association between area-specific X inactivation of the endometrial surface and the endometrial receptivity of embryo implantation remains to be clarified. 相似文献
19.
Thrombocytosis in preterm infants: a possible involvement of thrombopoietin receptor gene expression 总被引:2,自引:0,他引:2
Nakayama H Ihara K Hikino S Yamamoto J Nagatomo T Takemoto M Hara T 《Journal of molecular medicine (Berlin, Germany)》2005,83(4):316-320
Transient thrombocytosis is commonly observed in preterm infants after birth, but its physiological mechanism is still unknown. To understand the mechanism of the transient thrombocytosis in preterm infants we firstly evaluated a correlation between platelet counts and thrombopoietin (TPO) levels in preterm infants and next c-mpl mRNA levels on platelets in healthy preterm infants longitudinally during a half-year of life. The mean platelet counts in 45 very low birth weight infants (mean gestational age 27.4±1.8 weeks, mean birth weight 1047±249 g) was 230±71×109/l just after birth and thereafter gradually increased to 579±178×109/l by 5 weeks of age. The platelet counts continued this level for about next 8 weeks. Serum TPO levels soon after birth and at 1 month of age were significantly higher than those at the age of 2–6 months. There was a significant negative correlation between platelet counts and serum TPO values. The c-mpl expression levels on platelets at birth and at 1 month of age tended to be lower than those on platelets from adults, and the c-mpl levels gradually increased through 6 months of age, although they were still lower than those of adults. Our results suggest that low expression of TPO receptor on platelets until 1 month after birth cause a decreased TPO clearance and keep a high level of free TPO in blood, thereby promoting platelet production from megakaryocytes or their progenitors in bone marrow, resulting in the subsequent thrombocytosis in preterm infants. 相似文献
20.
Kasahara K Taguchi T Yamasaki I Kamada M Yuri K Shuin T 《Cancer Genetics and Cytogenetics》2002,137(1):59-63
In this study, we examined nine cases of advanced Japanese prostate cancer by comparative genomic hybridization (CGH) to detect chromosomal imbalances across the entire genome and to identify several new regions likely to contain genes important to the development and progression of this disease. These cases had been previously examined for numerical chromosomal aberrations by fluorescence in situ hybridization (FISH). By CGH, the following regions were found to be over-represented (gains), with fluorescence ratio values higher than the threshold: 4p, 6p, 8q, 11q, 12q, 15q, 16p, 17q, 20, and 21 (>4 cases); underrepresentation (losses) involved: 1q, 4q, 5q, 6q, 13q, 14q, and 22 (>4 cases). The shortest regions of overlap (SRO) of gains were noted at 8q24.1 through q24.3, 12q23, and 17q23 through q24 (>5 cases). The SRO of losses were seen at 5q14 through q21, 6q16.1 through q21, 13q21.3 through q22, and 14q21 (>5 cases). Notably, the gain of chromosomes 8 and 12 by CGH was in agreement with the FISH data, suggesting that the gain of chromosomes 8 and 12 may play an important role in prostate carcinogenesis. The genes on the SRO regions were also discussed in relation to oncogenes and bone metastases. 相似文献