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131.
Naoko Tanda Shiro Mori Masato Nose Tetsuo Saito Shi-Taek Song Atsushi Sato Teiichi Teshima 《Pathology international》1996,46(9):639-645
The expression of -GlcNAcβ1–6Man-(β1–6) branched oligosaccharides In carcinoma cells has been considered to influence their metastatic potentials. In the present paper, the lectin histochemistry of oral squamous cell carcinomas obtained in biopsy from 34 patients with Phaseolus vulgaris leukoagglutinin (L-PHA), which potentially binds to N-glycosidic carbohydrates with β1–6 linked lactosamin antennae, was studied in order to analyze the relationship between their staining patterns and metastases. The L-PHA-binding oligosaccharides of the carcinomas were expressed on the cell surface in the following patterns: (i) all cells were positive for the staining ('positive'); (ii) some cells were positive but the rest of the carcinoma cells were negative ('weakly positive'); and (iii) all were negative ('negative'). Statistical analysis revealed that the incidence of the metastasis to regional lymph nodes in the 'positive' cases was significantly higher than that in the 'negative' cases. Moreover, the number of the CD14 positive cells including macrophages in the Stroma adjacent to the cardnomas in the 'positive' cases was less than that in the 'negative' or 'weakly positive' cases. The expression of L-PHA-binding oligosaccharides in oral squamous cell carcinoma may be responsible for their metastatic potential to regional lymph nodes, possibly Including their ability to escape macrophage recognition. 相似文献
132.
Miura N Yamamoto M Fukutake M Ohtake N Iizuka S Ishige A Sasaki H Fukuda K Yamamoto T Hayakawa S 《International immunology》2005,17(5):513-522
Recent studies have suggested that Fas-mediated apoptosis is involved in the pathogenesis of intestinal injury. In this study, we determined the role of Fas/Fas ligand (FasL) interactions in different T cell compartments using a murine model of small intestinal injury. An intraperitoneal injection of 145-2C11 (anti-CD3) antibody into C3H/HeN, BALB/c and MRL mice induced mucosal flattening and rapid, bi-phasic intestinal epithelial cell (IEC) apoptosis, which was detected by conventional light and electron microscopy and by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling. In the first, early phase, villous apoptosis was observed up to 4 h after injection, and in the second, later phase, apoptotic crypt cells gradually accumulated for up to 24 h. The early and later phases of apoptosis were reduced in lpr/lpr and nude mice compared with those in control strains. In addition, the kinetics of Fas-mediated killer activity induced by the antibody injection were different between intestinal intraepithelial lymphocytes (IEL) and splenocytes (SPL) and seemed to correlate with the bi-phasic occurrence of the apoptosis. Finally, the transfer of intestinal IEL from euthymic to nude mice induced both phases of apoptosis, whereas SPL induced the second phase's crypt apoptosis only by the antibody injection. Together, these results suggest the involvement of Fas-mediated killer activity of thymus-derived T cells in different compartments. Namely, T cell populations in different compartments are differentially involved in the induction of IEC apoptosis and contribute to the complex pathogenesis of immune-mediated intestinal injury in which Fas/FasL interactions may play a critical role. 相似文献
133.
The reasons for the high accumulation of glutamate (Glu), aspartate (Asp) and glutamine (Gin) in high K and high glutathione
(HK/HG) dog red blood cells (DRBCs) have been explained as due to enhanced Glu/Asp influxes. However, in our study, Glu/Asp
influxes in high K and low glutathione (HK/LG) DRBCs were low, whereas their cellular Asp and Gin contents were high. In low
K (LK) DRBCs, there were also other variant cells with high Asp accumulation, but extremely low Glu/Asp influxes. So, the
high amino acid accumulation in DRBCs of these new variants might not be due to Glu/Asp influxes. To examine the high accumulation
of these amino acids in these variant DRBCs, first, LK and HK/LG DRBCs were classified into two subgroups with their Na-dependent
Glu/Asp influxes; one had clear Na-dependent Glu/Asp transport (GAT+), and the other failed to have any transport (GAT−). The influxes of both Glu and Asp in HK/HG DRBCs were the highest, and the order was HK/HG>LK/GAT+>HK/LG/GAT+>>LK/GAT−=HK/LG/GAT−. LK/GAT+ cells represented normal DRBCs. Glu/Asp influxes were only trace in both LK/GAT− and HK/LG/GAT− cells, but Glu and Asp concentration was high in HK/LG/GAT− cells whereas Asp concentration was high in LK/GAT− cells. In HK/HG cells, the conversion of Glu into Gin in whole cells was several fold higher than in the other cell groups
due to the differing amount of the substrate of glutamine synthetase, Glu, but glutamine synthetase activity itself was not
different among these cell groups. Furthermore, glutamine synthetase and glutaminase activities were not different among the
cell groups. Therefore, these enzymes were not involved in the high amino acid accumulation. 相似文献
134.
Induction of intestinal mastocytosis in nude mice by repeated injection of interleukin-3 总被引:4,自引:0,他引:4
T Abe H Ochiai Y Minamishima Y Nawa 《International archives of allergy and applied immunology》1988,86(3):356-358
The number of mast cells in various tissues of nude mice was examined after daily injection of Interleukin-3 (IL-3), which was purified from the media conditioned by WEHI-3B cell line. Repeated intraperitoneal injection of IL-3 caused a significant increase in the number of mucosal mast cells (MMC) in the epithelium of small intestine more than 30-fold and also to a lesser extent in the villous lamina propria of small intestine and caecum. The number of mast cells in the spleen, approximately 60% of which were formalin-resistant and were assumed as connective tissue type mast cells (CTMC), increased 3-fold by IL-3 treatment. Although statistically not significant, the number of mast cells in the ear skin also slightly increased. 相似文献
135.
Ochiai K Otaka K Ito M Tomioka H 《International archives of allergy and immunology》2001,124(1-3):237-241
Tyrosine phosphorylation of STAT1alpha in eosinophils after IFN-gamma stimulation has been shown, but the biological significance of eosinophil STAT1alpha activation in transmitting the signals through the IFN-gamma receptor remains unknown. The purpose of this study is to determine whether STAT1 is involved in the regulation of eosinophils by IFN-gamma-IFN-gamma receptor interaction. rhIL-3- and rhIL-5-induced eosinophils from CD34+ cells of cord blood on day 28 of culture were used. The cells were washed and further incubated in IL-3- and IL-5-free medium for 48 h. The induced eosinophils constitutively expressed CD69 and lost this expression after a further 48-hour incubation without the cytokines. IFN-gamma significantly upregulated CD69 expression on the 48-hour incubated cells. In inhibitory experiments on STAT1, a phosphorothioate oligo antisense DNA against STAT1alpha was added to IL-3- and IL-5-containing medium from day 15 to day 28 of culture. The oligo DNAs altered neither the expressions of myeloid cell marker CD9 and 13 nor the expression of IFN-gamma receptor on the cells. The added STAT1alpha antisense, but not sense, DNA significantly reduced STAT1alpha mRNA expression in the cells. The STAT1 antisense also significantly inhibited IFN-gamma-induced CD69 expression on the 48-hour incubated eosinophils. In conclusion, these results indicate that IFN-gamma induces CD69 expression in the induced eosinophils through STAT1alpha, suggesting that STAT1alpha may play a significant role in eosinophil regulation by IFN-gamma. 相似文献
136.
Kunikata T Yamane H Segi E Matsuoka T Sugimoto Y Tanaka S Tanaka H Nagai H Ichikawa A Narumiya S 《Nature immunology》2005,6(5):524-531
Prostaglandins, including PGD(2) and PGE(2), are produced during allergic reactions. Although PGD(2) is an important mediator of allergic responses, aspirin-like drugs that inhibit prostaglandin synthesis are generally ineffective in allergic disorders, suggesting that another prostaglandin-mediated pathway prevents the development of allergic reactions. Here we show that such a pathway may be mediated by PGE(2) acting at the prostaglandin E receptor EP3. Mice lacking EP3 developed allergic inflammation that was much more pronounced than that in wild-type mice or mice deficient in other prostaglandin E receptor subtypes. Conversely, an EP3-selective agonist suppressed the inflammation. This suppression was effective when the agonist was administered 3 h after antigen challenge and was associated with inhibition of allergy-related gene expression. Thus, the PGE(2)-EP3 pathway is an important negative modulator of allergic reactions. 相似文献
137.
Shigeru Sanada Atsushi Ando Itsuko Ando Tatsunosuke Hiraki Kinichi Hisada 《European journal of nuclear medicine and molecular imaging》1986,12(8):390-393
A single-strip miniaturized paper chromatographic method (Mini-PC) was developed using 80%–90% acetone solvent for rapid purity-control of 99mTc-radiopharmaceuticals. Routine 99mTc-radiopharmaceuticals (eight kinds of kit made agents) and diluted agents (in which radiochemical impurities might be formed) were analyzed by Mini-PC and other methods. This showed that, compared with the other methods, the Mini-PC technique is useful for the simple and rapid routine analysis of radiochemical impurities of kit made 99mTc-radiopharmaceuticals. 相似文献
138.
Yusuke Komiya Makoto Sugiyama Masaru Ochiai Nanako Osawa Yuto Adachi Shugo Iseki Keizo Arihara 《Nutrients》2021,13(4)
Olive oil is a functional food shown to have a variety of bioactive effects. Therefore, we expect it to be a novel functional food with an exercise-mimetic effect on skeletal muscles. This study aimed to investigate the effect of olive oil on the endurance capacity and muscle metabolism in mice. Mice fed a 7% (w/w) olive oil diet for eight weeks showed improved treadmill running endurance and increased intramuscular triacylglycerol (IMTG) accumulation in the gastrocnemius muscle compared to soybean oil diet-fed controls. The increase in running endurance with olive oil intake was independent of the muscle fiber type. To elucidate underlying the mechanism of elevated IMTG levels, we examined the expression levels of the genes related to lipid metabolism. We found that the expression of diacylglycerol O-acyltransferase1 (DGAT1) was significantly upregulated in the muscle of olive oil diet-fed mice. In addition, the olive oil diet-fed mice showed no metabolic impairment or differences in growth profiles compared to the controls. These results suggest that dietary olive oil intake affects muscle metabolism and muscle endurance by increasing energy accumulation. 相似文献
139.
Probiotics have been suggested to be effective for functional dyspepsia, but their effect on gastric motility is not clear. We evaluated the effect of Lactobacillus gasseri OLL2716 (LG21 strain) on mild to moderate delayed gastric emptying by a double-blind, parallel-group, placebo-controlled, randomized trial. Participants (n = 28) were randomly assigned to ingest LG21 strain-containing yogurt (LG21 strain group) or LG21 strain-free yogurt (placebo group) for 12 weeks. The 13C gastric emptying breath test was performed to measure the gastric emptying rate over time following ingestion of a liquid meal, and the time to reach the peak (Tmax) was used as an indicator of gastric emptying. We also measured the salivary amylase concentration, an indicator of autonomic dysfunction under stress. The per-protocol population (n = 27, male n = 4, female n = 23) was evaluated for efficacy. When a ≥30% reduction in the difference between participant’s Tmax and the Japanese mean Tmax was defined as an improvement, the odds ratio of improvement in delayed gastric emptying compared to placebo after 12 weeks was 4.1 (95% confidence interval, 0.8 to 20.2). Moreover, salivary amylase concentrations were significantly lower than in the placebo group, indicating an improvement in autonomic function. The present data were not enough to support the beneficial effects of the LG21 strain on delayed gastric emptying. However, if we define the odds ratio in further study investigated with a larger number of participants, LG21 strain might be expected to have some impact on delayed gastric emptying. 相似文献