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141.
Pregnane glycosides previously isolated from genus Caralluma (C. Penicillata, C. tuberculata and C. russelliana) were tested for their antitrypanosomal activity. Penicilloside E showed the highest antitrypanosomal activity (IC50 1.01 μg/ml) followed by caratuberside C (IC50 1.85 μg/ml), which exhibited the highest selectivity index (SI 12.04). It was noticed that acylation is required for the antitrypanosomal activity while glycosylation at C-20 has no significant effect on the activity.  相似文献   
142.
Lymphotoxin-β (LT-β) has been suggested to be a regulator of secondary lymphoid structure development. In the present study, we isolated porcine LT-β (poLT-β) from adult swine spleens. The open reading frame encoded a predicted 246-amino acid polypeptide exhibiting higher similarity to the human than the mouse LT-β protein. Expression of LT-β mRNA in various swine tissues was analyzed by real-time PCR, and it was found to be higher in the ileal Peyer's patches (Pps) of adults than in newborns. In addition, ligand stimulation of toll-like receptors 2, 4, and 9, which are activated by bacterial components, increased LT-β expression only in neonatal ileal Pps. These results suggest that colonization by commensal bacteria may affect the maturation of neonatal ileal Pps by the induction of LT-β via toll-like receptors. LT-β may therefore be useful for studying the development of the intestinal immune system at parturition in both swine and humans.  相似文献   
143.
Endothelial progenitor cells (EPCs) are a subset of the total mononuclear cell population (tMNCs) that possess an enhanced potential for differentiation within the endothelial‐cell lineage. Typically, EPCs are selected from tMNCs via the expression of both hematopoietic stem‐cell markers and endothelial‐cell markers, such as CD34, or by culturing tMNCs in media selective for endothelial cells. Both EPCs and tMNCs participate in vascular growth and regeneration, and their potential use for treatment of myocardial injury or disease has been evaluated in early‐phase clinical studies. Direct comparisons between EPCs and tMNCs are rare, but the available evidence appears to favor EPCs, particularly CD34+ cells, and the potency of EPCs may be increased as much as 30‐fold through genetic modification. However, these observations must be interpreted with caution because clinical investigations of EPC therapy are ongoing. We anticipate that with continued development, EPC therapy will become a safe and effective treatment option for patients with acute myocardial infarction or chronic ischemic disease. J. Cell. Physiol. 219: 235–242, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   
144.
We compared the effect of the rice storage protein glutelin B-1 (GluB-1) terminator with the nopaline synthase (Nos) terminator on the accumulation of the modified house dust mite allergen mDer f 2 driven by the maize ubiquitin promoter in transgenic rice. Accumulation of mDer f 2 in transgenic seed and leaf using the GluB-1 terminator was greater than when using the Nos terminator construct. The mDer f 2 mRNA containing the GluB-1 3′UTR was processed and polyadenylated at the same sites as the native GluB-1 mRNA in the seeds but diverged in leaves of the transgenic plants. In contrast, the poly(A) sites of mDer f 2 containing Nos 3′UTR were more divergent in both seed and leaf. These results suggest that GluB-1 3′UTR functions as a faithful terminator and that termination at the specific sites may play an important role in mRNA stability and/or translatability, resulting in higher levels of protein accumulation.  相似文献   
145.
Membranous epithelial cells (M cells) of the follicle-associated epithelium in Peyer’s patches have a high capacity for transcytosis of several viruses and microorganisms. Here, we report that we have successfully established a bovine intestinal epithelial cell line (BIE cells) and developed an in vitro M cell model. BIE cells have a cobblestone morphology and microvilli-like structures, and strongly express cell-to-cell junctional proteins and cytokeratin, which is a specific intermediate filament protein of epithelial cells. After co-culture with murine intestinal lymphocytes or treatment with supernatant from bovine PBMC cultured with IL-2, BIE cells acquired the ability of transcytosis. Therefore, BIE cells have typical characteristics of bovine intestinal epithelial cells and also have the ability to differentiate into an M cell like linage. In addition, our results indicate that contact between immune cells and epithelial cells may not be absolutely required for the differentiation of M cells. We think that BIE cells will be useful for studying the transport mechanisms of various pathogens and also the evaluation of drug delivery via M cells.  相似文献   
146.
Treatment of Nylon wool-passed cells (NWC) prepared from the spleen of C57BL/6 mice with IL-18 and IL-12, but not with IL-18 alone, resulted in induction of IFN-gamma, a Th1 cytokine, and GM-CSF at 24 h, and IL-13, a Th2 cytokine at 72 h. The induction of IL-13 was suppressed by anti-GM-CSF antibody, indicating involvement of GM-CSF in IL-13 production. When NWC incubated with IL-18 and IL-12 for 72 h ("primary treatment") were treated again with the same cytokines ("secondary treatment"), IL-13 was induced much more quickly than observed in the primary treatment. Flow cytometric analysis of NWC after the primary treatment showed marked increases in the CD4(-)CD8(-) non-T cell population bearing CD25(+), CD45RB(super high) and CD122(+). These cells were positive for CD49b but negative for NK1.1, indicating that they were not typical but NK-like cells. The NK-like cells produced IL-13 in response to the treatment with IL-18 alone, indicating that the generation of these cells in the primary treatment likely accounts for the quick production of IL-13 in the secondary treatment. These results show that IL-18 and IL-12 generates the NK-like cells in NWC by a process mediated by GM-CSF that are ready for producing IL-13.  相似文献   
147.
Structures of three pectic arabinogalactans, one from Vernonia kotschyana (Vk2a) and two from Cochlospermum tinctorium (Ct50A1 and Ct50A2), and their complement fixation and induction of B cell proliferation in vitro were compared. The polysaccharide Vk2a expressed potent biological activity in both assays compared with Ct50A1 and Ct50A2. Vk2a possessed a very high molecular weight (1150 +/- 20 kDa) compared with Ct50A1 and Ct50A2 which both showed a polydisperse nature with the highest molecular weight polymers in each fraction estimated at approximately 105 kDa (Ct1a) and 640 +/- 100 kDa (Ct2a), respectively. The HMW polymers showed complement fixation in the same range as the native fractions. The arabinogalactan II content was low in Vk2a (2%) compared with that in Ct50A1 (23%) and Ct50A2 (12%). The high molecular weight polymers were subjected to digestion with a beta-d-(1, 3)-galactanase-rich fraction from Driselase, oligomers were isolated by HPAEC, and their finer structures were determined by MALDI- and ES-qoToF-MS, linkage, and monosaccharide composition analyses. Vk2a consists of both a galacturonan core and a rhamnogalacturonan core rich in neutral side chains. The backbones of both Ct-polysaccharides consist mainly of RG-I regions with numerous neutral side chains dominated by galactosyl residues, whereas the homogalacturonan regions seem to be small. Differences in the chain lengths of the 6-linked galacto-oligosaccharides attached to the 3-linked galactan core could not be related to the differences in the potencies of the biological activities observed.  相似文献   
148.
Hepatic stellate cells play a major role in retinylester storage in mammals, but the retinoid-storing state in nonmammalian vertebrates remains to be elucidated. In this study, we examined retinoids and retinoid-storing cells in the arrowtooth halibut, Atheresthes evermanni. High-performance liquid chromatography analyses revealed the highest concentrations of stored retinoids (retinol and retinylester, 6199 nmol/g) in the pyloric cecum, a teleost-specific organ protruding from the intestine adjacent to the pylorus. Considerable amounts of retinoids were also stored in the intestine (3355 nmol/g) and liver (1891 nmol/g), and small amounts in the kidney (102 nmol/g). Very small amounts or no retinoids were detected in the heart, gill, skeletal muscle, and gonads (less than 2 nmol/g). Use of gold chloride staining and fluorescence microscopy to detect retinoid autofluorescence showed that, in the pyloric cecum and intestine, retinoid-storing cells were localized in the lamina propria mucosae. Under electron microscopy, cells containing well-developed lipid droplets, which are common morphological characteristics of the hepatic stellate cells of mammals, were observed in the lamina propria mucosae of the pyloric cecum. Thus, the distribution of stellate cells with retinoid-storing capacity differs between this halibut and mammals, suggesting that the retinoid-storing site has shifted during vertebrate evolution.  相似文献   
149.
Two new species of Marasmiellus (Tricholomataceae, Agaricales) are described and illustrated from Japan: (1) Marasmiellus crassitunicatus sp. nov. (subsection Inodermini of section Marasmiellus) forms dark reddish-brown, orbicular to reniform basidiomata constantly accompanied by tufts of short filiform rhizomorphs, growing on the bark of living coniferous or broad-leaved trees; and (2) Marasmiellus vernalis sp. nov. (subsection Quercini of section Dealbati) forms small brown basidiomata with nondiverticulate pileipellis elements, growing on the bark of living Pinus thunbergii in spring (April to June).  相似文献   
150.
Prostaglandin (PG) D(2) ethanolamide (prostamide D(2)) was reduced to 9alpha,11beta-PGF(2) ethanolamide (9alpha,11beta-prostamide F(2)) by PGF synthase, which also catalyzes the reduction of PGH(2) and PGD(2) to PGF(2alpha) and 9alpha,11beta-PGF(2), respectively. These enzyme activities were measured by a new method, the liquid chromatographic-electrospray ionization-mass spectrometry (LC/ESI/MS) technique, which could simultaneously detect the substrate and all products. PGF(2alpha), 9alpha,11beta-PGF(2), PGD(2), PGH(2), 9alpha,11beta-prostamide F(2), and prostamide D(2) were separated on a TSKgel ODS 80Ts column, ionized by electrospray, and detected in the negative mode. Selected ion monitoring (SIM) of m/z 353 ([M-H](-)), 353 ([M-H](-)), 351 ([M-H](-)), 333 ([M-H-H(2)O](-)), 456 ([M+59](-)), and m/z 358 ([M-37](-)) was used for quantifying PGF(2alpha), 9alpha,11beta-PGF(2), PGD(2), PGH(2), 9alpha,11beta-prostamide F(2), and prostamide D(2), respectively. The detection limit for PGF(2alpha) and 9alpha,11beta-PGF(2) was 0.01pmol; that for PGH(2) and PGD(2), 0.1pmol; and that for prostamide D(2) and 9alpha,11beta-prostamide F(2), 0.5 and 0.03pmol, respectively. The LC/ESI/MS technique for measuring PGF synthase activity showed higher sensitivity than other methods. Using this method, we found that Bimatoprost, the ethyl amide analog of 17-phenyl-trinor PGF(2alpha) and an anti-glaucoma agent, inhibited all three reductase activities of PGF synthase when used at a low concentration. These results suggest that Bimatoprost also behaves as a potent PGF synthase inhibitor in addition to having prostamide-like activity.  相似文献   
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