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Polysaccharide Fraction (polysaccharide + fraction)
Selected AbstractsMeasurement of blood clearance time by Limulus G test of Candida -water soluble polysaccharide fraction, CAWS, in miceFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2000Kiyoshi Kurihara Abstract The Limulus G test, responsive to ,-1,3- d -glucan, is a well-established method for the detection of invasive fungal infection. We have recently found that Candida albicans released a water-soluble polysaccharide fraction (CAWS) into synthetic medium (Uchiyama et al., FEMS Immunol. Med. Microbiol. 24 (1999) 411,420). CAWS was composed of a mannoprotein-,-glucan complex and activated Limulus factor G, and thus would be similar to the Limulus active substance in patient's blood. In a preliminary investigation, we have found that CAWS is lethal when administered intravenously in a murine system. In this study, we examined the toxicity and then the fate of CAWS in mice. The lethal toxicity was strain-dependent and strain DBA/2 was the most resistant. The toxicity was, at least in part, reduced by salbutamol sulfate and prednisolone treatment in the sensitive strains. On intravenous administration, the half clearance time (t1/2) was approximately 40 min in mice (DBA/2). On intraperitoneal administration, CAWS appeared in the blood with a peak concentration at 1 h. In order to establish a treatment plan, it is important to demonstrate the onset and the termination of deep-seated mycosis. The Limulus G test is suitable for the above purpose; however, it is necessary to fully understand the fate of ,-1,3- d -glucan in patients' blood [source] Immunopotentiation on murine spleen lymphocytes induced by polysaccharide fraction of Panax ginseng via upregulating calcineurin activityAPMIS, Issue 4 2010SONG-DONG ZHANG Zhang S-D, Yin Y-X, Wei Q. Immunopotentiation on murine spleen lymphocytes induced by polysaccharide fraction of Panax ginseng via upregulating calcineurin activity. APMIS 2010; 118: 288,96. Calcineurin (CN), a unique Ca2+/calmodulin (CaM)-dependent serine/threonine protein phosphatase, plays a pivotal role in the activation and proliferation of T lymphocytes. Based on the effective molecular screening model established in our laboratory, we found that a part of polysaccharides from the stem and leaves of Panax ginseng, termed PGP-SL, could activate CN activity. Subsequently, we investigated whether PGP-SL also has immunological competence on murine spleen lymphocytes. In the present study, we demonstrated that PGP-SL could significantly promote in vitro spleen lymphocyte proliferation in the absence of either concanavalin A or LPS in a concentration-dependent manner at concentrations ranging from 100 to 500 ,g/ml (p < 0.001). In addition, the proliferation of cyclosporin A (CsA)-treated spleen lymphocytes was also significantly promoted in the same pattern (p < 0.001); the production of IL-2 was elevated and the effect appeared as early as 24 h after PGP-SL treatment. The results of RT-PCR also indicated that the IL-2 mRNA level was markedly enhanced, particularly at PGP-SL concentrations of 300 and 500 ,g/ml, and Fura-2/AM fluorescence probe analysis showed that PGP-SL could dramatically increase the intracellular free calcium concentration of spleen lymphocytes, i.e. [Ca2+]i was significantly increased by approximately 181 and 107% at 300 and 500 ,g/ml of PGP-SL, respectively. However, this effect could be totally inhibited by verapamil treatment. Taking our results together, we suggest that PGP-SL exhibits immunopotentiation effects on murine spleen lymphocytes by the Ca2+,CN,NFAT,IL-2 signaling pathway. [source] Studies on bioemulsifier production by Acinetobacter strains isolated from healthy human skinJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2001J.R. Patil Aims: In recent years, interest has been growing in the search for novel bioemulsifiers. Many bacterial genera including Acinetobacter have been reported to produce bioemulsifiers. The present study aims to screen Acinetobacter isolates from healthy human skin for bioemulsifier production. Methods and Results: Acinetobacter junii SC14 produced maximum bioemulsifier in the presence of almond oil during stationary growth phase at 37°C and pH 7·2. Partially purified, nondialysable bioemulsifier from SC14 was a proteoglycan. The protein and polysaccharide fractions resulted in 95·2% reconstitution of the emulsification activity. The role of esterase in the release of cell-bound emulsifier and the contribution of capsular polysaccharide to the emulsification activity were observed. Conclusion:Acinetobacter strains from human skin exhibited better emulsification activity than that by burn wound or soil isolates, owing to the inherent differences in chemical microenvironment of their habitats. Significance and Impact of the Study: Investigation of skin commensals, especially acinetobacters, would lead to the discovery of novel bioemulsifiers with interesting properties. Attempts of screening and strain improvement directed towards skin commensals will open up new avenues for strains producing bioemulsifier on a commercial scale. [source] Sedum telephium L. Polysaccharide Content Affects MRC5 Cell Adhesion to Laminin and FibronectinJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 5 2000L. RAIMONDI In traditional medicine the fresh leaves and juice of Sedum telephium L. are used as wound-healing promoters. Cell adhesion represents a primary event in wound repair and in tissue homeostasis, and therefore we have investigated the effect of Sedum juice and its main fractions, polysaccharides and flavonols, on human fibroblast (MRC5) adhesion to fibronectin and laminin. Our findings revealed that total Sedum juice strongly inhibited cell adhesion to laminin and fibronectin (EC50 1.03 ± 0.12 mg mL,1). This anti-adhesive feature was concentrated mainly in the two polysaccharide fractions (EC50 values comprised between 0.09 and 0.44 mg mL,1). The flavonol fractions did not seem to contribute to this effect. A first attempt to elucidate the polysaccharide-related anti-adhesive feature of Sedum juice was also performed. The results confirmed that natural polysaccharides, with chemical structures different from heparin, were able to interfere with integrin-mediated cell behaviour and they contributed to the outstanding effects of Sedum juice and to the role of polysaccharides in cell-matrix interaction. [source] | ||||||||||