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1.
Fatty acid composition of lipids from polished rice was studied by gas chromatography on the separated fractions, fat-by-hydrolysis, neutral fat, free fatty acid and phospholipid. After six months storage, fatty acids were released from neutral fat in the same proportion as they were combined in the neutral fat.  相似文献   
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Recent studies have indicated that macrophage migration inhibitory factor (MIF) and Toll-like receptor (TLR) play an important role in the regulation of innate immune responses. In this study, we investigated the effect of MIF on the expression of TLR4, a receptor that recognizes lipopolysaccharide, in colon using MIF-deficient mice. TLR4 mRNA expression in the colon tissues was determined by northern blot analysis. Western blot analysis and immunohistochemistry in the colon tissues were performed to evaluate the expression of TLR4 protein. The expressions of TLR4 mRNA and protein were remarkably down-regulated in colon tissues of MIF-deficient mice compared with wild-type mice and up-regulated by treatment with recombinant MIF. Immunohistochemical study revealed the presence of TLR4–positive staining in mononuclear cells in the lamina propria and intraepithelial mononuclear cells as well as weak staining in epithelial cells and crypts in colon tissues of wild-type mice. In contrast, MIF-deficient mice did not show TLR4-positive staining in the colonic mucosa. In MIF-deficient mice injected with recombinant mouse MIF (rMIF), TLR4-positive staining cells were observed in colon tissues similar to the findings in wild-type mice. Administration of dextran sulfate sodium (DSS) up-regulated the expression of TLR4 in the colons of WT mice but not in those of MIF-deficient mice. Furthermore, pretreatment with rMIF up-regulated the expression of TLR4 in response to DSS in MIF-deficient mice. Our results suggest that MIF affects the expression of TLR4 in mouse colon under both normal and colitic conditions.An erratum to this article can be found at  相似文献   
3.
Abstract. We investigated the seasonal prevalence of reproductive activities and of the development of brooded propagules in an intertidal sea anemone, Anthopleura sp., on the rocky shore of Mutsu Bay, in northern Japan. A monthly examination of anemones, by dissection and histological techniques, revealed no sign of gonad development, but did reveal that they produce and internally brood propagules throughout the year. Release of propagules was observed in the field. This anemone population appears to be entirely asexual and agametic, and may persist solely through clonal propagation.  相似文献   
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BACKGROUND: Macrophage migration inhibitory factor (MIF) was recently rediscovered as a cytokine, pituitary hormone, and glucocorticoid-induced immunomodulator. MIF is constitutively expressed in various cells and enhances production of inflammatory cytokines such as tumor necrosis factor-alpha, interleukin-1, and interferon gamma. Recently, it was reported that MIF mRNA was overexpressed in prostatic tumors, which suggests that MIF is a protein involved in tumor cell growth beyond inflammatory and immune responses. MATERIALS AND METHODS: We examined the expression of MIF in the murine colon carcinoma cell line colon 26 by Western and Northern blot analyses and immunohistochemistry. Next, we investigated the effects of transforming growth factor (TGF) beta, basic fibroblast growth factor (b-FGF), and platelet-derived growth factor (PDGF) on the expression of MIF mRNA. Furthermore, we examined whether MIF is involved in tumor cell proliferation, using an MIF anti-sense plasmid transfection technique. RESULTS: We demonstrated that MIF protein and its mRNA were highly expressed in colon 26 cells, using Western and Northern blot analyses, respectively. By immunohistochemical analysis, we found that MIF was localized largely in the cytoplasm of the tumor cells. In response to TGF-beta, b-FGF, and PDGF, MIF mRNA expression was significantly up-regulated. Following this, we transfected the cells with an anti-sense MIF plasmid, which revealed that this treatment induced significant suppression of cell proliferation. CONCLUSION: Although MIF plays multifunctional roles in a broad spectrum of pathophysiological states, little has been done to investigate the role of this protein in association with tumor growth. The current results suggest the possibility that MIF induces tumor cell growth in concert with other growth factors, which encouraged us to investigate a novel approach for tumor therapy using an anti-MIF antibody and an MIF anti-sense plasmid transfection technique.  相似文献   
6.
Histochemical staining for enzymes is usually performed on frozen sections. This report lists the longer incubation times required to demonstrate esterase, acid phosphatase, β-galactosidase, and cytochrome oxidase in plastic embedded and routine paraffin embedded tissues. The sections embedded in plastic, i.e. water soluble methacrylate (Polyscience's JB-4) and cut at 2 μm, were far superior to frozen Sections and paraffin embedded sections both in tissue detail and in the localization of the histochemical reaction product.  相似文献   
7.
Levels of protein kinase C activity in human gastrointestinal cancers   总被引:1,自引:0,他引:1  
The protein kinase C (PKC) activities of tumor tissue and adjacent normal mucosa of human cancers of the esophagus (8 cases), stomach (1 case) and colon (3 cases) were measured. Considerable variations were found in the activity of PKC and in its subcellular distribution in these cancers. The PKC activities of the membrane and cytosolic fractions of the eight esophageal cancers were, however, similar to those of the adjacent normal mucosa: the average PKC activities of the tumor tissues and normal mucosa were 7.5 and 8.3 pmol/min/mg protein, respectively, in their membrane fractions and 7.9 and 7.8 pmol/min/mg protein, respectively, in their cytosolic fractions.  相似文献   
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In contrast to our previous report (Biochem. Biophys. Res. Comm. 134:587, 1986), we now find that protein kinase C (PKC) is mobilized in human polymorphonuclear neutrophils (PMN) stimulated with platelet-activating factor (PAF) or leukotriene (LT)B4. Thus nanomolar concentrations of each compound caused PMN to lose cytosolic, PKC-specific protein phosphorylating activity, as well as receptors for phorbol myristate acetate (PMA). Smaller gains in membrane-associated PMA receptors accompanied these changes. Diacylglycerol and PMA had very similar effects on PKC. However, unlike these direct PKC activators, PAF and LTB4 induced only moderate decreases in cytosolic PKC; acted only on PMN pretreated with cytochalasin B; did not mobilize PKC in disrupted PMN or activate PKC in a cell-free system; and with respect to PAF, induced responses that partially reversed within 30 min. Furthermore, PAF, LTB4, and several of their structural analogues mobilized PKC at concentrations correlating closely with their respective affinities for cellular LTB4 or PAF receptors. Thus PAF and LTB4 acted by indirect and apparently receptor-mediated mechanisms. Four observations indicated that the cytochalasin B-dependent degranulating actions of PAF and LTB4 involved PKC. First, PKC mobilization and degranulation occurred at the same stimulus concentrations. Second, 5-hydroxyicosatetraenoate dramatically enhanced both PKC mobilization and degranulation when elicited by PAF; it had relatively little influence on LTB4-induced responses. Third, PAF-induced mobilization (t1/2 less than 7 sec) preceded degranulation (t1/2 approximately 20 sec). Finally, a PKC blocker, polymyxin B, was similarly effective in inhibiting degranulation responses to PAF, LTB4, and PMA. Because stimulated PMN may produce and use PAF, LTB4, and 5-hydroxyicosatetraenoate as secondary intracellular mediators, our results implicate PKC as a central and potentially critical regulator of function.  相似文献   
10.
Fluorescent DNA probes for L-argininamide were developed by a combination of DNA aptamers and fluorophore-quencher pairs. These molecules were synthesized by a combination of pre- and post-synthetic modification methods. The fluorescence-labeled aptamer could detect L-argininamide specifically. The binding affinities were defined by the binding affinity of the original aptamer to indicate that the end labeling of the aptamer did not influence the affinities.  相似文献   
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