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31.
Yoshiji Asaoka Tokuma Yanai Haruko Hirayama Yumi Une Eriko Saito Hiroki Sakai 《Avian pathology》2004,33(1):19-24
Sporadic outbreaks of fatal enteritis occurred among free-living wild crows (‘large billed’ or ‘wok’ crow; Corvus macrorhynchos) in an open-air park in Japan in 2002. Eight crows were found dead during February, followed by two more in September, and five of the eight were examined histopathologically. At necropsy, all cases showed a markedly dilated small intestine, especially the jejunum and ileum, with large amounts of gas, and dark red to greenish–brown soft content. The necrotic intestinal wall was markedly thickened with multifocal haemorrhages. All cases had multifocal white foci in the liver, and four cases showed marked splenomegaly. Histologically, there was severe necrotic enteritis characterized by extensive mucosal necrosis and multifocal haemorrhages, as well as inflammatory cell infiltrations. A prominent pseudo-membrane formation was noted in the affected intestine. Severe adhesive peritonitis was also observed in three cases. Gram-positive bacilli were present in large numbers in the lumen, and in and around necrotic lesions in the affected intestine. The bacilli were positive for Clostridium perfringens enterotoxin type A by immunohistochemistry, and were also positive for C. perfringens type A using the immunofluorescence method. C. perfringens was isolated by anaerobic culture from the intestinal contents. The present enteritis was thought to be induced by proliferated C. perfringens in the intestine, and to be the cause of death. 相似文献
32.
Iwasaki Y Shibata N Ninomiya M Kurita K Nakabayash N Ishihara K 《Journal of biomaterials science. Polymer edition》2002,13(3):323-335
Heparinization is believed to be one of the methods to suppress thrombus formation on blood-contacting surfaces. However, this study hypothesizes that heparinization alone might not be sufficient to provide a blood-compatible surface; that is, a surface property that resists biofouling is necessary to obtain an effective heparin-modified surface. 2-Methacryloyloxyethyl phosphorylcholine (MPC) polymers with 2-aminoethyl methacrylate (AEMA) were synthesized to immobilize heparin through ionic bonding. The primary amino groups of AEMA were considered to be the polymer surface because the zeta-potential of the surface was positive when the mole fraction of the AEMA units was above 0.2. The antithrombogenic character of the polymer surface modified with heparin was evaluated by both Lee-White and microsphere column methods. The coagulation period of human whole blood in the absence of anticoagulant in glass tubing coated with the MPC polymer was longer than that in the original glass tube. Cell adhesion was completely inhibited on the MPC polymer surface after contact with human whole blood without anticoagulant. However, many adherent blood cells were observed on poly(2-ethylhexyl methacrylate-co-AEMA) (no MPC unit) even after heparinization. These results strongly indicate that the MPC polymer is a useful substrate where the heparin works well and that the heparin-immobilized MPC polymer has superior blood compatibility to the simple MPC polymer. 相似文献
33.
Accelerated Loss of Islet β Cells in Sucrose-Fed Goto-Kakizaki Rats, a Genetic Model of Non-Insulin-Dependent Diabetes Mellitus
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Motoi Koyama Ryu-ichi Wada Hiroyasu Sakuraba Hiroki Mizukami Soroku Yagihashi 《The American journal of pathology》1998,153(2):537-545
The Goto-Kakizaki (GK) rat is a spontaneously diabetic animal model of non-insulin-dependent diabetes mellitus, which is characterized by progressive loss of β cells in the pancreatic islets with fibrosis. In the present study, we examined the effects of sucrose feeding on the islet pathology in this model. Six-week-old GK rats were fed with 30% sucrose for 6 weeks to induce severe hyperglycemia, and their condition was compared with that of nontreated rats. Age-matched normal Wistar rats were also given sucrose for the same periods and used for comparison. The sucrose-treated GK rats showed elevated blood glucose levels on oral glucose tolerance tests at 60 minutes and 120 minutes, representing 123% and 127% of values in untreated GK rats, respectively. At the end of the study, the mean β-cell volume density in GK rats was 50% less than that in untreated Wistar rats. Sucrose feeding further reduced the volume densities of β cells to only 50% of the levels of age-matched GK rats. Apoptotic cells were found in islet β cells only in GK rats fed sucrose (mean 0.067%). There appeared to be more islets that immunohistochemically stained strongly positive with 8-hydroxy-deoxyguanosine as a marker of oxidative damage of DNA in GK rats fed sucrose compared with those not given sucrose. GK rats not fed sucrose showed significantly lower proliferative activity of β cells measured by 5-bromo-2′-deoxyuridine uptake and intensified expression of Bcl-2 immunoreactivities at 6 weeks of age compared with those in age-matched Wistar rats. These two indices were reduced in both GK and Wistar rats with increasing age and were not affected by sucrose feeding in either group. The present study thus indicated that sucrose feeding promoted the apoptosis of β cells in GK rats through increased oxidative stress without altering their proliferative activity. 相似文献
34.
Expression of cytoplasmic TFF2 is a marker of tumor metastasis and negative prognostic factor in gastric cancer 总被引:8,自引:0,他引:8
Dhar DK Wang TC Maruyama R Udagawa J Kubota H Fuji T Tachibana M Ono T Otani H Nagasue N 《Laboratory investigation; a journal of technical methods and pathology》2003,83(9):1343-1352
Trefoil factor family 2 (TFF2) is a small peptide constitutively expressed in the gastric mucosa, where it plays a protective role in restitution of gastric mucosa. TFF2 has also been shown to be expressed in some gastric cancers, but its role in tumor metastasis and patient prognosis has not been examined. In this study, we examined TFF2 expression at both the mRNA and protein levels and correlated these results with the clinicopathologic characteristics and prognosis of gastric cancer patients. Among the 144 curatively resected samples, 43 (30%) were positive for TFF2. TFF2 expression was preferentially observed in the infiltrating tumor cells sparing the superficial cells. Significantly increased expression of TFF2 was noted in large tumors of the diffuse type. An increased prevalence of TFF2 expression was also found in tumors with advanced T and N stage and in patients with lymphatic and venous invasion. Accordingly, patients with TFF2-expressing tumors had a significantly worse disease-free survival, and in multivariate analysis, this finding remained significant as an independent prognostic factor. Taken together, our results suggest that TFF2 expression may play a role in gastric cancer invasion and as such could be a useful target for therapeutic intervention. 相似文献
35.
Biological properties and gene expression associated with metastatic potential of human osteosarcoma 总被引:4,自引:0,他引:4
Nakano T Tani M Ishibashi Y Kimura K Park YB Imaizumi N Tsuda H Aoyagi K Sasaki H Ohwada S Yokota J 《Clinical & experimental metastasis》2003,20(7):665-674
Lung metastasis has a great influence on the prognosis of patients with osteosarcoma. We previously established two high-metastatic
sublines, M112 and M132, from the HuO9 human osteosarcoma cell line by in vivo selection. In this study, we newly isolated a high-metastatic subline, H3, and three low-metastatic sublines, L6, L12 and
L13, from HuO9 by the dilution plating method. Three high-metastatic sublines produced more than 200 metastatic nodules in
the lung, while three low-metastatic sublines produced no or few nodules after injection of 2 × 106 cells into the tail vein of nude mice. There were significant differences in the motility and invasiveness between high-
and low-metastatic sublines, whereas the growth rates in vitro and the tumorigenicity in vivo showed no correlation with their metastatic abilities. Early adherence to culture plates was significantly lower in two of
three low-metastatic sublines, which occupied smaller surface areas on the culture plates than other sublines did. Comparison
of the expression of 637 cancer-related genes by cDNA microarray revealed that seven genes were differentially expressed between
high- and low-metastatic sublines. Among them, five genes (AXL, TGFA, COLL7A1, WNT5A, and MKK6) were associated with adherence, motility, and/or invasiveness. These results suggest that the differences in motility/invasiveness
and adhesive abilities are key determinants of lung metastasis in osteosarcoma.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
36.
WSX-1 is required for resistance to Trypanosoma cruzi infection by regulation of proinflammatory cytokine production 总被引:6,自引:0,他引:6
Hamano S Himeno K Miyazaki Y Ishii K Yamanaka A Takeda A Zhang M Hisaeda H Mak TW Yoshimura A Yoshida H 《Immunity》2003,19(5):657-667
WSX-1 is a class I cytokine receptor with homology to the IL-12 receptors and is essential for resistance to Leishmania major infection. In the present study, we demonstrated that WSX-1 was also required for resistance to Trypanosoma cruzi. WSX-1-/- mice exhibited prolonged parasitemia, severe liver injury, and increased mortality over wild-type mice. WSX-1-/- splenocytes produced enhanced levels of Th2 cytokines, which were responsible for the prolonged parasitemia. Massive necroinflammatory lesions were observed in the liver of infected WSX-1-/- mice, and IFN-gamma that was overproduced in WSX-1-/- mice compared with wild-type mice was responsible for the lesions. In addition, vast amounts of various proinflammatory cytokines, including IL-6 and TNF-alpha, were produced by liver mononuclear cells in WSX-1-/- mice. Thus, during T. cruzi infection, WSX-1 suppresses liver injury by regulating production of proinflammatory cytokines, while controlling parasitemia by suppression of Th2 responses, demonstrating its novel role as an inhibitory regulator of cytokine production. 相似文献
37.
Yoshihisa Umekita Nobumasa Enokizono Yoshiatsu Sagara Kazumi Kuriwaki Takashi Takasaki Aichi Yoshida Hiroki Yoshida 《Virchows Archiv : an international journal of pathology》1992,420(4):345-351
Summary In this investigation, 83 human mammary carcinomas were examined for the expression of oestrogen receptor (ER), epidermal growth factor receptor (EGF-R), epidermal growth factor (EGF), transforming growth factor alpha (TGF-), c-erbB-2, histological grade, mitotic index and nodal status, all of which are reportedly prognostically significant factors (Bloom and Richardson 1957; Baak et al. 1985; Wright et al. 1989). ER expression was biochemically recognized in 43.4% of mammary carcinomas, and EGF-R, EGF, TGF- and c-erbB-2 were histochemically recognized in 25.3, 14.5, 27.7 and 18.0% of mammary carcinomas examined respectively, using conventional sections of buffered formalin-fixed, paraffin-embedded tissue and monoclonal or polyclonal antibodies. There were significant relationships between negative ER and positive EGF-R or TGF-; positive EGF-R and TGF-; positive EGF-R and c-erbB-2; and positive c-erbB-2 and TGF-. The single changes which were the negative ER and the positive c-erbB-2 correlated with histological grade and mitotic index. Co-expression of EGF-R and TGF- correlated with positive nodal status. Therefore, the present investigation indicates that the negative ER, single expression of c-erbB-2 and co-expression of EGF-R and TGF- are important markers which contribute indirectly to prognosis, which reconfirms previous findings on the former two while adding the new finding that immuno-histochemical demonstration of expression of EGF-R and TGF- may provide useful information for selecting the appropriate treatment. 相似文献
38.
Shoichi Fujita Eisei Shin Tsutomu Nakamura Hiroki Kurahashi Yasufumi Kaneda Kiyoji Tanaka Takesada Mori Shin-ichiro Takai Isamu Nishisho 《Journal of human genetics》1993,38(4):361-370
Summary Radiation-reduced hybrids for mapping of DNA markers in the pericentromeric region of chromosome 10 were developed. A Chinese hamster/human somatic cell hybrid (762-8A) carrying chromosomes 10 and Y as the only human material were exposed to 40,000 rads of irradiation and then rescued by fusion with non-irradiated recipient Chinese hamster cells (GM459). Southern hybridization analyses revealed that 10 of 128 HAT-resistant clones contained human chromosomal fragments corresponding to at least one marker locus betweenFNRB (10p-11.2) andRBP3 (10q11.2). These hybrids were then used to map microdissection clones previously isolated and roughly mapped to this chromosomal region by fluorescencein situ hybridization (FISH). Two of the six microclones studied could be mapped to the proximity of the D10-S102 locus. These radiation hybrids are useful for the construction of refined genetic maps of the pericentromeric region of chromosome 10. 相似文献
39.
K Mizuno K Satomura A Miyamoto K Arakawa T Shibuya T Arai A Kurita H Nakamura J A Ambrose 《The New England journal of medicine》1992,326(5):287-291
BACKGROUND. Disruption of an atherosclerotic plaque in a coronary artery followed by the formation of a thrombus is believed to be the cause of both unstable angina and acute myocardial infarction. Although thrombolytic therapy is efficacious in patients with acute myocardial infarction, for unknown reasons it is far less effective in patients with unstable angina. We postulated that there might be differences in the composition of the coronary-artery thrombi in unstable angina and acute myocardial infarction. METHODS. To investigate the appearance of coronary-artery thrombi, we performed percutaneous transluminal coronary angioscopy in 15 patients with unstable angina and 16 with acute myocardial infarction. Angioscopy was performed within 48 hours after an episode of pain at rest in the patients with unstable angina and within 8 hours of onset in those with acute myocardial infarction. RESULTS. Angioscopy revealed coronary thrombi in all but two patients (one in each group). Of the 29 patients with thrombi, those with unstable angina were frequently observed to have grayish-white thrombi (10 of 14, 71 percent), but none were seen in the 15 patients with acute myocardial infarction (P less than 0.01). By contrast, reddish thrombi were observed in all 15 patients with acute myocardial infarction who had thrombi, but in only 4 of the 14 patients with unstable angina and thrombi (P less than 0.01). As assessed by coronary angiography, occlusive thrombi occurred frequently in patients with acute myocardial infarction (13 of 16 patients) but were not seen in any of the 15 patients with unstable angina (P less than 0.01). CONCLUSIONS. Coronary-artery thrombi play an important part in the pathogenesis of unstable angina and acute myocardial infarction. However, the appearance of the thrombi is different in the two conditions, possibly reflecting differences in the composition of age of the thrombi or the presence or absence of blood flow in the artery. This difference may account for the contrasting results of thrombolytic therapy. 相似文献
40.
Hiroki Otani Osamu Tanaka Kei-Ichiro Kasai Takafumi Yoshioka 《Anatomical record (Hoboken, N.J. : 2007)》1988,222(1):26-33
Morphologic changes in the development of the mitochondrial helical sheath in the mouse spermatid tail were examined with the scanning electron microscope (SEM) using the osmium-DMSO-osmium method and classified into several stages. During late spermiogenesis, spherical mitochondria gathered around the forming spermatid tail. The shape of these mitochondria gradually changed from spheroid to long and rod-like. Mitochondria first were arranged in four longitudinal rows (stage 1) that twisted dextrally, and the mitochondria began to stagger (stage 2). They became elongated and arranged into a staggered pattern; they then attached to each other in an end-to-end fashion to form a sinistral double helix around the core of the axoneme (stage 3). These end-to-end contacts were observed in every second gyre on the four lines surrounding the core of the axoneme at stage 3. Mitochondria further elongated and end-on touching appeared with every third gyre on the five longitudinal lines that surround the core of the axoneme (stage 4). The direction of the helix, always sinistral, was clearly discernible only in the later stages. Disposition of the mitochondria in the spermatid tail was regular throughout development, which indicates that these mitochondria elongate simultaneously and also at the same rate. On any given cracked surface of the seminiferous tubule, spermatid tails with the same stage of mitochondria predominantly were observed. This ultrastructural finding appears compatible with the histologic synchronism, (termed the “wave”) in differentiating germ cells. 相似文献