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61.
Detection of specific antibody in adult human periodontitis sera to surface antigens of Bacteroides gingivalis. 总被引:1,自引:6,他引:1 下载免费PDF全文
Sera from adult periodontitis patients were analyzed for antibody activity against surface antigens of Bacteroides gingivalis by immunoblotting analysis. 相似文献
62.
Numerical aberrations of chromosome 9 in bladder cancer. A possible prognostic marker for early tumor recurrence 总被引:3,自引:0,他引:3
Tsukamoto M Matsuyama H Oba K Yoshihiro S Takahashi M Naito K 《Cancer Genetics and Cytogenetics》2002,132(1):41-45
Bilharzial bladder cancer is one of the most common types of malignancy in both men and women in several developing countries including Egypt. It has several unique clinical, epidemiological, and histological characteristics, suggesting that it is an entity distinct from bladder cancer seen in Western countries. Genetic alterations in bilharzial-related bladder cancer have been studied infrequently, especially in the advanced stages of disease, that is, T3 and T4 classifications. The objective of this study was to extend establishing the baseline cytogenetic profile of this type of malignancy to early T1 and T2 classifications. For this purpose, fluorescence in situ hybridization was applied to interphase nuclei of frozen-stored samples with biotinylated repetitive DNA probes specific for all chromosomes to detect numerical chromosome changes in 35 patients presenting with relatively early-stage pT1 and pT2 disease. Eleven cases had squamous cell carcinoma (SCC) and 24 had transitional cell carcinoma. Six of 24 transitional cell carcinomas had diploid chromosome counts with all the probes. Numerical chromosome aberrations were detected in 18 cases (75%). In 12 cases, a loss of chromosome 9 was observed. In three cases, an additional loss of chromosome 17 was detected. One case demonstrated a loss of chromosome 10, whereas another two cases showed a gain of chromosome 7, next to a loss of chromosome 9. Loss of chromosome Y was observed in nine of the 27 male cases studied (33.3%), in which only one case showed an abnormality whereas four cases were detected next to loss of chromosome 9, and one case showed gain of chromosome 7. Five cases showed loss of chromosome 19 whereas gain of chromosome 4 was detected in two cases. Two of 11 samples of SCC had normal diploid chromosome counts with all the probes used. In four of 11 cases (36.4%) underrepresentation of chromosome 9, compared with the other chromosomes, was detected. An additional loss of chromosome 17 and gain of chromosome 7, next to loss of chromosome 9, was detected in three cases. One case showed loss of chromosome 17 as the only numerical aberration. Loss of the Y chromosome was detected in three cases of which one case had gain of chromosome 7 and one case had loss of chromosome 19. No correlation was found between any of the clinicopathologic parameters examined in this study and the presence or absence of any numerical chromosomal aberrations except for the significant association between schistosomal history and loss of Y chromosome (P=0.007). 相似文献
63.
Toshio Nishimura Keizo Tsuruhara Keiko Naito Junko Hirohara Sotokichi Morii 《Pathology international》1989,39(5):281-288
To examine the effect of colchicine on ethionine induced fatty liver, adult female rats were starved overnight and then injected i.p. with 1 g kg ethionine at 11th hour of fasting; then a half of the rats were also injected i.p. with 2.5 mg kg colchicine twice at 3 and 6 h after the single administration of ethionine. Similarly, fasted control rats were injected i.p. with vehicle alone at the above times. All of the rats were sacrificed after a 20 h fast, and the hepatocytes in periportal areas were observed ultra-structurally. In addition, total lipids in the liver tissue were extracted and determined biochemically. Although similar significant increases of triglyceride were observed in the liver tissue of all ethionine-injected rats, the hapatocytes in the group treated with both chemicals had fewer cytoplasmic fat globules (CFG) than those in the group treated with ethionine only. On the other hand, the diameters of markedly increased membrane-bound lipid particles (MLP) in the double treated group were distributed mainly in the range 0.2–0.4 μm, compared with those (0.1-0.2 μm) in the other groups. These findings indicate that colchicine inhibits the development of CFG in ethionine injured hapatocytes. Acta Pathol Jpn 39: 281∼288, 1989. 相似文献
64.
Coombes JS Powers SK Demirel HA Jessup J Vincent HK Hamilton KL Naito H Shanely RA Sen CK Packer L Ji LL 《Acta physiologica Scandinavica》2000,169(4):261-269
Reactive oxygen species (ROS) contribute significantly to myocardial ischaemia-reperfusion (I-R) injury. Recently the combination of the antioxidants vitamin E (VE) and alpha-lipoic acid (alpha-LA) has been reported to improve cardiac performance and reduce myocardial lipid peroxidation during in vitro I-R. The purpose of these experiments was to investigate the effects of VE and alpha-LA supplementation on cardiac performance, incidence of dysrhythmias and biochemical alterations during an in vivo myocardial I-R insult. Female Sprague-Dawley rats (4-months old) were assigned to one of the two dietary treatments: (1) control diet (CON) or (2) VE and alpha-LA supplementation (ANTIOXID). The CON diet was prepared to meet AIN-93M standards, which contains 75 IU VE kg-1 diet. The ANTIOXID diet contained 10 000 IU VE kg(-1) diet and 1.65 g alpha-LA kg(-1) diet. After the 14-week feeding period, significant differences (P<0.05) existed in mean myocardial VE levels between dietary groups. Animals in each experimental group were subjected to an in vivo I-R protocol which included 25 min of left anterior coronary artery occlusion followed by 10 min of reperfusion. No group differences (P>0.05) existed in cardiac performance (e.g. peak arterial pressure or ventricular work) or the incidence of ventricular dysrhythmias during the I-R protocol. Following I-R, two markers of lipid peroxidation were lower (P<0.05) in the ANTIOXID animals compared with CON. These data indicate that dietary supplementation of the antioxidants, VE and alpha-LA do not influence cardiac performance or the incidence of dysrhythmias but do decrease lipid peroxidation during in vivo I-R in young adult rats. 相似文献
65.
Shiro Ohshima Yukihiko Saeki Toru Mima Mitsuko Sasai Katsuhiro Nishioka Hiroshi Ishida Masatoshi Shimizu Masaki Suemura Richard McCloskey Tadamitsu Kishimoto 《Journal of clinical immunology》1999,19(5):305-313
To investigate the mechanism of the long-lasting efficacy of chimeric monoclonal anti-TNF antibody (cA2) therapy for rheumatoid arthritis (RA), eight patients with refractory RA were treated with a single infusion of cA2 and the changes in circulating cytokines (IL-1, IL-6, TNF, and IL-10), soluble cytokine receptors (TNF-RI, RII, and sIL-6R) and peripheral white blood cell (WBC) subset counts were followed up long-term (12 weeks) after cA2 therapy in them. Significant clinical responses (>20% improvement according to Paulus' criteria) were observed just after cA2 infusion and lasted more than 4 weeks in all patients, as reported elsewhere. Moreover, five of the eight patients showed prolonged clinical responses (>12 weeks). The elevated serum IL-6 and sTNF-RI (or RII) levels before treatment rapidly decreased after treatment. The serum IL-10 levels also significantly elevated before treatment. The elevations of serum IL-10 levels were augmented after treatment and stayed higher than the baseline in four patients with prolonged clinical responses. No significant TNF, IL-1 and -, or sIL-6R were detected in the sera of the patients before treatment and during the whole study period. On the other hand, peripheral lymphocytes as well as total WBC and neutrophils increased for 4 weeks after treatment. However, thereafter, only the lymphocyte count decreased gradually and stayed below the baseline long-term (12 weeks). FACS analysis revealed the predominance of T lymphocytes in the decrease in lymphocyte counts. These results suggest that the augmentation of IL-10 production and the decrease in T cells might partly contribute to the long-lasting efficacy of cA2 treatment in RA. 相似文献
66.
Nishio J Iwasaki H Sakashita N Haraoka S Isayama T Naito M Miyayama H Yamashita Y Kikuchi M 《Human pathology》2003,34(3):246-252
Undifferentiated (embryonal) sarcoma of the liver (UESL) is a rare pediatric liver malignancy that is extremely uncommon in middle-aged individuals. We studied 2 cases of UESL in middle-aged adults (1 case in a 49-year-old woman and the other in a 62-year-old man) by histology, immunohistochemistry, and electron microscopy to clarify the cellular characteristics of this peculiar tumor. One tumor showed a mixture of spindle cells, polygonal cells, and multinucleated giant cells within a myxoid matrix and also revealed focal areas of a storiform pattern in a metastatic lesion. The other tumor was composed mainly of anaplastic large cells admixed with few fibrous or spindle-shaped components and many multinucleated giant cells. In both cases, some tumor cells contained eosinophilic hyaline globules that were diastase resistant and periodic acid-Schiff positive. Immunohistochemically, the tumor cells showed positive staining for smooth muscle markers, such as desmin, alpha-smooth muscle actin, and muscle-specific actin, and also for histiocytic markers, such as alpha-1-antitrypsin, alpha-1-antichymotrypsin, and CD68. Electron microscope examination revealed thin myofilaments with focal densities and intermediate filaments in the cytoplasm of tumor cells. Our studies suggest that UESL exhibits at least a partial smooth muscle phenotype in middle-aged adults, and this specific differentiation may be more common in this age group than in children. Tumor cells of UESL with smooth muscle differentiation in middle-aged adults show phenotypic diversity comparable to those of malignant fibrous histiocytoma with myofibroblastic differentiation. 相似文献
67.
Gondo S Yanase T Okabe T Tanaka T Morinaga H Nomura M Goto K Nawata H 《Genes to cells : devoted to molecular & cellular mechanisms》2004,9(12):1239-1247
Bone marrow stem cells develop into haematopoietic and mesenchymal lineages, but have not been known to participate in steroidogenic cell production. Steroidogenic factor 1 (SF-1), also designated adrenal 4 binding protein (Ad4BP), is an essential orphan nuclear receptor for steroidogenesis as well as for adrenal and gonadal gland development. In the present study, we revealed that the adenovirus-mediated forced expression of SF-1 can transform cultured primary long-term cultured bone marrow cells into steroidogenic cells, showing the de novo synthesis of multiple steroid hormones in response to adrenocorticotropic hormone (ACTH). This finding may provide an initial step in innovative autograft cell transfer therapy for steroid hormone deficiencies. 相似文献
68.
Hamada K Sasaki T Koni PA Natsui M Kishimoto H Sasaki J Yajima N Horie Y Hasegawa G Naito M Miyazaki J Suda T Itoh H Nakao K Mak TW Nakano T Suzuki A 《Genes & development》2005,19(17):2054-2065
PTEN is an important tumor suppressor gene. Hereditary mutation of PTEN causes tumor-susceptibility diseases such as Cowden disease. We used the Cre-loxP system to generate an endothelial cell-specific mutation of Pten (Tie2CrePten) in mice. Tie2CrePten(flox/+) mice displayed enhanced tumorigenesis due to an increase in angiogenesis driven by vascular growth factors. This effect was partially dependent on the PI3K subunits p85alpha and p110gamma. In vitro, Tie2CrePten(flox/+) endothelial cells showed enhanced proliferation/migration. Tie2CrePten(flox/flox) mice died before embryonic day 11.5 (E11.5) due to bleeding and cardiac failure caused by impaired recruitment of pericytes and vascular smooth muscle cells to blood vessels, and of cardiomyocytes to the endocardium. These phenotypes depend strongly on p110gamma rather than on p85alpha and were associated with decreased expression of Ang-1, VCAM-1, connexin 40, and ephrinB2 but increased expression of Ang-2, VEGF-A, VEGFR1, and VEGFR2. Pten is thus indispensable for normal cardiovascular morphogenesis and post-natal angiogenesis, including tumor angiogenesis. 相似文献
69.
Nascent peptide-mediated translation elongation arrest coupled with mRNA degradation in the CGS1 gene of Arabidopsis 下载免费PDF全文
Onouchi H Nagami Y Haraguchi Y Nakamoto M Nishimura Y Sakurai R Nagao N Kawasaki D Kadokura Y Naito S 《Genes & development》2005,19(15):1799-1810
Expression of the Arabidopsis CGS1 gene that codes for cystathionine gamma-synthase is feedback regulated at the step of mRNA stability in response to S-adenosyl-L-methionine (AdoMet). A short stretch of amino acid sequence, called the MTO1 region, encoded by the first exon of CGS1 itself is involved in this regulation. Here, we demonstrate, using a cell-free system, that AdoMet induces temporal translation elongation arrest at the Ser-94 codon located immediately downstream of the MTO1 region, by analyzing a translation intermediate and performing primer extension inhibition (toeprint) analysis. This translation arrest precedes the formation of a degradation intermediate of CGS1 mRNA, which has its 5' end points near the 5' edge of the stalled ribosome. The position of ribosome stalling also suggests that the MTO1 region in nascent peptide resides in the ribosomal exit tunnel when translation elongation is temporarily arrested. In addition to the MTO1 region amino acid sequence, downstream Trp-93 is also important for the AdoMet-induced translation arrest. This is the first example of nascent peptide-mediated translation elongation arrest coupled with mRNA degradation in eukaryotes. Furthermore, our data suggest that the ribosome stalls at the step of translocation rather than at the step of peptidyl transfer. 相似文献
70.
Kayo Adachi Michihiko Momota Yoshiki Teranishi Reiko Ueki Masatoshi Hagiwara Takashi Wakabayashi Jerzy Popinigis 《Pathology international》1992,42(8):549-557
The physicochemical properties of mitochondria in liver tissue obtained from rats given 32% ethanol, 32% propanol or 6.9% butanol in drinking water for up to 3 months were investigated using differential scanning calo-rimetry and fluorescence polarization measurements. The results obtained were as follows: 1) Phospholipids extracted from mitochondria showed increases in the relative amounts of phosphatidylcholine, phosphatidylinositol and phosphatidylserine, and a decrease in the relative amount of phosphatidylethanolamine. An increase in the unsatu-rated/saturated fatty acid ratio of phospholipids was also observed. 2) Elevation of the thermotropic lipid phase transition temperature with a decrease in the enthalpy value (δ H ) was revealed by differential scanning calo-rimetry. 3) The elevation of the lipid phase transition temperature was detected also by fluorescence polarization measurements using 1,6 diphenyl 1, 3, 5 hexatriene (DPH) as a probe. Elevation of mitochondrial membrane fluidity was found in some of the experimental animals, but most showed no changes in comparison with the control. A possible role of membrane fusion in the mechanism of formation of ethanol-, propanol- and butanol induced hepatic megamitochondria is discussed on the basis of these results. Acta Pathol Jpn 42: 549–557, 1992. 相似文献