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A polysaccharide DOTP-80 from Dioscorea opposita Thunb was obtained by using the method of acid water-extraction and ethanol-precipitation. After being purified by chromatography, the structure characteristics of DOTP-80 were established. Based on the calibration curve obtained with standard dextrans, the molecular weight of the polysaccharide fraction DOTP-80 was calculated to be 123 kDa. The results of Infrared spectrum (FT-IR) indicated that the polysaccharide contained the á-configuration of sugar units. GC-MS analysis revealed that DOTP-80 was mainly composed of mannose and glucose. Alloxan-induced diabetic rats and mice models were developed to evaluate the in vivo hypoglycemic activity of the polysaccharide. The results indicated that a high dose DOTP-80 (400 mg/kg) had strong hypoglycemic activity. Moreover, DOTP-80 could increase the level of antioxidant enzymes (SOD) activity in alloxan-induced diabetic mice and stimulate an increase in glucose disposal in diabetic rats. Therefore, the polysaccharide DOTP-80 should be evaluated as a candidate for future studies on diabetes mellitus. [ABSTRACT FROM AUTHOR]

A water-soluble polysaccharide from Sarcodia ceylonensis was obtained by using the method of water-extraction and ethanol-precipitation. The polysaccharide was further purified by chromatography on AB-8 and ADS-7 columns, yielding a pure polysaccharide termed SCP-60. The molecular weight (Mw) of SCP-60 was calculated to be 50.0 kDa, based on the calibration curve obtained with a series of Dextran T standards. The results of FT-IR indicated that the polysaccharide contains the α-configuration of sugar units. GC-MS analysis revealed that SCP-60 was mainly composed of galactose and glucose. NMR spectroscopy revealed SCP-60 had the backbone consisting of →6)-α-Manp-(1→, α-D-Glcp-(1→, →6)-α-D-Glcp-(1→ and →6)-α-Galp-(1→. In order to evaluate the antitumor activity in vivo of the polysaccharide, a sarcoma 180 model was used. The results showed SCP-60 had strong antitumor ability, meanwhile, SCP-60 at a high dose (100 mg/kg) could significantly increase the thymic and splenic indices of S180 mice, and strongly promote the secretion of IL-2, TNF-α and IFN-γ, increase the SOD activities and reduce the concentrations of MDA in blood. Therefore the polysaccharide SCP-60 should be explored as a novel potential antitumor drug. [ABSTRACT FROM AUTHOR]

A water-soluble crude polysaccharide (DFHP) obtained from the aqueous extracts of the stem of Dendrobium fimhriatum Hook.var.oculatum Hook through hot water extraction followed by ethanol precipitation, was found to have an average molecular weight (Mw) of about 209.3 kDa. Monosaccharide analysis revealed that DFHP was composed of mannose, glucose and galactose in a content ratio of 37.52%; 43.16%; 19.32%. The investigation of antioxidant activity in vitro showed that DFHP is a potential antioxidant. [ABSTRACT FROM AUTHOR]

Liver disease associated with cystic fibrosis (CF) has been increasingly diagnosed and recognized as one of the major causes of death in CF during recent years. The autosomal-recessive disorder of CF results from mutation of the cystic fibrosis transmembrane conductance regulator (CFTR) that encodes the CFTR protein. Due to its existence and multifunction in biliary epithelial, over- or less-expression of CFTR in the liver may play an important role in the development of CF liver disease (CFLD). The aim of current study is to investigate the expression of CFTR in the liver of common bile duct ligated (BDL) rats. After BDL, there was an increase in the abundance of CFTR mRNA and protein. Immunohistochemical staining also demonstrated an increased intensity of CFTR staining in the liver tissue section. In conclusion, there is an increased expression of CFTR in the liver after common BDL. 2004 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Objective: In order to investigate the antioxidant activities of polysaccharides (BPL-1 and BPL-2), one of the most important functional constituents in Brasenia schreberi was isolated from the external mucilage of B. schreberi (BPL-1) and the plant in vivo (BPL-2). This paper examines the relationship between the content of sulfuric radicals and uronic acid in BPL and the antioxidant activity of BPL. Materials and Methods:The free radicals, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+) and 1,1-diphnyl-2-picrylhydrazyl (DPPH-), were used to determine the antioxidant activity of BPL. The Fourier-transform infrared spectroscopy of BPL-1 and BPL-2 revealed typical characteristics of polysaccharides. Results: The two sample types had different contents. This was proved by their different adsorption peak intensities. The IC50 values of BPL-1 (31.189 mg/ml) and BPL-2 (1.863 mg/ml) showed significant DPPH radical scavenging activity. Based on the quantification of ABTS radical scavenging, the IC50 value of BPL-1 (5.460 mg/ml) was higher than that of BPL-2 (0.239 mg/ml). Therefore, in terms of the reducing power, the IC50 value of BPL-1 was too high to determine, and the IC50 value of BPL-2 was found to be 50.557 mg/ml. Hence, the antioxidant activity and total reducing power were high, and they were greater in BPL-2 than in BPL-1. In addition, BPL-2 was found to have more sulfuric radicals and uronic acid than BPL-1. Conclusion: The contents of sulfuric radicals and uronic acid are significantly correlated to the antioxidant activity and reducing power of BPL; the more sulfuric radicals and uronic acid, the more antioxidant activity and reducing power BPL has. [ABSTRACT FROM AUTHOR]

The water-soluble crude polysaccharide (DDP) obtained from the aqueous extracts of the stem of Dendrobium denneanum through hot water extraction followed by ethanol precipitation, was found to have an average molecular weight (Mw) of about 484.7 kDa. Monosaccharide analysis revealed that DDP was composed of arabinose, xylose, mannose, glucose and galactose in a molar ratio of 1.00:2.66:8.92:34.20:10.16. The investigation of antioxidant activity both in vitro and in vivo showed that DDP is a potential antioxidant. [ABSTRACT FROM AUTHOR]

Background: Tuberculosis is a mycobacterial infection causing worldwide public health problems but the available vaccine is far from ideal. Type-1 T cell immunity has been shown to be critical for host defence against tuberculosis infection, but the role of dendritic cell (DC) subsets in pathogenesis of mycobacterial infection remains unclear. Methodology/Principal Findings: We examined the effectiveness of dendritic cell (DC) subsets in BCG-infected mice in generating immune responses beneficial for pathogen clearance and reduction of pathological reactions in the tissues following challenge infection. Our data showed that only the adoptive transfer of the subset of CD8α+ DC isolated from infected mice (iCD8+ DC) generated significant protection, demonstrated by less mycobacterial growth and pathological changes in the lung and liver tissues in iCD8+ DC recipients than sham-treated control mice. The adoptive transfer of the CD8α-DC from the infected mice (iCD8- DC) not only failed to reduce bacterial growth, but enhanced inflammation characterized by diffuse heavy cellular infiltration. Notably, iCD8- DC produced significantly higher levels of IL-10 than iCD8+ DC and promoted more Th2 cytokine responses in in vitro DC-T cell co-culture and in vivo adoptive transfer experiments. Conclusions/Significance: The data indicate that in vivo BCG-primed CD8+DCis the dominant DC subset in inducing protective immunity especially for reducing pathological reactions in infected tissues. The finding has implications for the rational improvement of the prophylactic and therapeutic approaches for controlling tuberculosis infection and related diseases. [ABSTRACT FROM AUTHOR]

The role of interleukin-22 (IL-22) in intracellular bacterial infections is a controversial issue, although the contribution of this cytokine to host defense against extracellular bacterial pathogens has been well established. In this study, we focused on an intracellular bacterium, Chlamydia, and evaluated the production and function of IL-22 in host defense against chlamydial lung infection using a mouse model. We found that Chlamydia muridarum infection elicited quick IL-22 responses in the lung, which increased during infection and were reduced when bacterial loads decreased. More importantly, blockade of endogenous IL-22 using neutralizing anti-IL-22 monoclonal antibodies (mAb) resulted in more severe disease in the mice, leading to significantly higher weight loss and bacterial growth and much more severe pathological changes than treatment with isotype control antibody. Immunological analyses identified significantly lower T helper 1 (Th1) and Th17 responses in the IL-22–neutralized mice. In contrast, intranasal administration of exogenous IL-22 significantly enhanced protection following chlamydial lung infection, which was associated with a significant increase of Th17 response. The data demonstrate that IL-22 is a critical cytokine, mediating host defense against chlamydial lung infection and coordinating the function of distinct Th-cell subsets, particularly Th1 and Th17, in the process. [ABSTRACT FROM AUTHOR]

A water-soluble polysaccharide (BEBP) was extracted from Boletus edulis Bull using hot water extraction followed by ethanol precipitation. The polysaccharide BEBP was further purified by chromatography on a DEAE-cellulose column, giving three major polysaccharide fractions termed BEBP-1, BEBP-2 and BEBP-3. In the next experiment, the average molecular weight (Mw), IR and monosaccharide compositional analysis of the three polysaccharide fractions were determined. The evaluation of antioxidant activities both in vitro and in vivo suggested that BEBP-3 had good potential antioxidant activity, and should be explored as a novel potential antioxidant. [ABSTRACT FROM AUTHOR]

Dendritic cells (DC) play a key role in establishing protective adaptive immunity in intracellular bacterial infections, but the cells influencing DC function in vivo remain unclear. In this study, we investigated the role of NK cells in modulating the function of DC using a murine Chlamydia infection model. We found that the NK cell-depleted mice showed exacerbated disease after respiratory tract Chlamydia muridarum infection, which was correlated with altered T cell cytokine profile. Furthermore, DC from C. muridarum-infected NK-depleted mice (NK-DC) exhibited a less mature phenotype compared with that of DC from the infected mice without NK depletion (NK+DC). NK-DC produced significantly lower levels of both IL-12 and IL-10 than those of NK+DC. Moreover, NK-DC showed reduced ability to direct primary and established Ag-specific Th1 CD4+ T cell responses in DC-T coculture systems. More importantly, adoptive transfer of NK-DC, in contrast to NK+DC, failed to induce type 1 protective immunity in recipients after challenge infection. Finally, NK cells showed strong direct enhancing effect on IL-12 production by DC in an NK-DC coculture system, which was partially reduced by blocking NKG2D receptors signaling and virtually abolished by neutralizing IFN-γ activity. The data demonstrate a critical role of NK cells in modulating DC function in an intracellular bacterial infection. [ABSTRACT FROM AUTHOR]

A supramolecular hydrogel based on d-amino acids, which resists hydrolysis catalyzed by proteinase K and offers long-term biostability, exhibits controlled release in vivo,as proved by the pharmacokinetics of encapsulated 125I tracers and the SPECT imaging of the hydrogel-encapsulated 131I tracers. As the first in vivo imaging investigation of the drug release properties of the supramolecular hydrogel, isotope encapsulation serves as a valid, useful assay for characterizing the controlled release properties of supramolecular hydrogels in vivo. Our results indicate that supramolecular hydrogels promise new biomaterials for controlled drug release. [ABSTRACT FROM AUTHOR]

Given a widespread interest in rough sets as being applied to various tasks of data analysis, it is not surprising at all that we have witnessed a wave of further generalizations and algorithmic enhancements of this original concept. In this study, we investigate an idea of rough fuzzy random sets. This construct provides us with a certain generalization of rough sets by introducing the concept of inclusion degree. The underlying objective behind this development is to address the problems which involve co-existing factors of fuzziness and randomness thus giving rise to a notion of the fuzzy random approximation space based on inclusion degree. Some essential properties of rough approximation operators of such rough fuzzy random sets are discussed. Further theoretical foundations for the formation of rules constructed on a basis of available decision tables are offered as well. [ABSTRACT FROM AUTHOR]

γ-Aminobutyric acid (GABA) is an important neurotransmitter that, through the subtype A GABA receptor (GABAAR), induces inhibition in the adult brain. Here we show that an excitatory, rather than inhibitory, GABAergic system exists in airway epithelial cells. Both GABAARs and the GABA synthetic enzyme glutamic acid decarboxylase (GAD) are expressed in pulmonary epithelial cells. Activation of GABAARs depolarized these cells. The expression of GAD in the cytosol and GABAARs in the apical membranes of airway epithelial cells increased markedly when mice were sensitized and then challenged with ovalbumin, an approach for inducing allergic asthmatic reactions. Similarly, GAD and GABAARs in airway epithelial cells of humans with asthma increased after allergen inhalation challenge. Intranasal application of selective GABAAR inhibitors suppressed the hyperplasia of goblet cells and the overproduction of mucus induced by ovalbumin or interleukin-13 in mice. These findings show that a previously unknown epithelial GABAergic system has an essential role in asthma. [ABSTRACT FROM AUTHOR]

Our previous work has shown that C3H/HeN and C57BL/6 mice have differential susceptibility to Chlamydia trachomatis mouse pneumonitis ( C. muridarum) lung infection. C3H/HeN (H-2k) mice were found to be highly susceptible to C. muridarum infection with higher mortality and more severe morbidity compared to C57BL/6 (H-2b) mice. To examine the role of major histocompatibility complex (MHC) genes on host resistance to chlamydial lung infection, we compared MHC congenic mice, B6.H2k [C57BL/6 background, C3H MHC (H-2k)] and C3H.H2b [C3H/HeN background, C57BL/6 MHC (H-2b)] and their corresponding wild type C57BL/6 mice and C3H/HeN mice, respectively, in susceptibility to C. muridarum infection. We found that B6.H2k, C3H.H2b and C3H/HeN mice are more susceptible to chlamydial lung infection compared to the wild type C57BL/6 mice by showing more serious body weight loss, higher in vivo chlamydial growth and more severe pathologic changes. Congenic B6.H2k mice showed significantly lower levels of IL-12 and IFN-γ production compared to C57BL/6 as well as C3H/HeN and C3H.H2b mice. One the other hand, although congenic C3H.H2b mice displayed similar cytokine response to C57BL/6 mice, they were highly susceptible to C. muridarum infection. Overall, the results suggest that protection against chlamydial lung infection is both MHC and non-MHC gene dependent, and that the interaction between MHC and non-MHC elements may contribute to host resistance to chlamydial infection. [ABSTRACT FROM AUTHOR]

Previous studies have shown that chlamydial infection is accompanied by significant infiltration of neutrophils at the site of infection. However, the role of neutrophils in host defence against chlamydial infection is not clearly understood. Using genetically different inbred mouse strains and CXCR-2 gene knockout (KO) mice, we examined the mechanism for neutrophil recruitment and the role of neutrophils during chlamydial lung infection. Our data showed that C3H mice exhibited significantly higher and more persistent neutrophil infiltration in the lung than did C57BL/6 mice followingChlamydia trachomatismouse pneumonitis infection. The massive neutrophil infiltration in C3H mice was paralleled by high-level expression of CXCR-2 and its ligands, CXC chemokines (macrophage inflammatory protein 2, cytokine-induced neutrophil attractant (KC)and lipopolysaccharide-induced CXC chemokine), and proinflammatory cytokines (tumour necrosis factor-α, interleukin-1 and interleukin-6) in the lung. Although much greater infiltration of neutrophils was observed in C3H mice than in C57BL/6 mice, the former mice had more severe disease and higherin vivochlamydial growth than the latter. Moreover, CXCR-2 KO mice, which revealed a dramatic reduction in neutrophil activity, showed comparable chlamydial infection to wild-type mice. These results suggest that neutrophils are not efficient for controlling chlamydial lung infection. [ABSTRACT FROM AUTHOR]

T-helper-1-like cytokine response and cell-mediated immunity have been shown to be critical in host resistance to Chlamydia trachomatis infection. Using a murine pneumonia model, we compared the susceptibility of C3H/HeN (C3H) and C57BL/6 mice to C. trachomatis mouse pneumonitis (MoPn) infection. C3H mice exhibited significantly higher mortality, greater organism growth and much more severe pathological changes in the lung compared with C57BL/6 mice. However, the pattern of adaptive immune responses including organism-specific delayed-type hypersensitivity, antibody responses and cytokine [interferon-γ (IFN-γ), interleukin-12 (IL-12), IL-4, IL-10 and tumour necrosis factor α] production by spleen and local draining lymph node cells in these two strains of mice appeared comparable during the process of infection. Interestingly, MoPn growth in the cultured ex vivo macrophages from C3H mice was found to be significantly less inhibited by the exogenous IFN-γ present in the culture compared to C57BL/6 mice. The lower inhibition of MoPn growth in C3H mice was associated with significantly lower nitric oxide production by the infected macrophages following IFN-γ stimulation. The data suggest that the cellular events downstream of cytokine production in chlamydia host cells may be important in determining the different susceptibility of hosts to chlamydial infection. [ABSTRACT FROM AUTHOR]