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911.
Singh S Khajuria A Taneja SC Khajuria RK Singh J Qazi GN 《Bioorganic & medicinal chemistry letters》2007,17(13):3706-3711
The present study revealed the synergistic effect of boswellic acid mixture (BA) and glucosamine for anti-inflammatory and anti-arthritic activities in rats. Two studies were conducted, that is, acute anti-inflammatory by carrageenan edema and chronic anti-arthritic by Mycobacterium-induced developing arthritis. Five groups of animals were included in each of the study: the vehicle control, positive control (ibuprofen 100mg/kg), boswellic acids (250 mg/kg), glucosamine (250 mg/kg) and a combination of boswellic acids (125 mg/kg) and glucosamine (125 mg/kg). BA when administered at 250 mg/kg in rats, carrageenan-induced paw edema and Mycobacterium-induced developing arthritis were significantly inhibited. In comparison to boswellic acids, glucosamine when administered at 250 mg/kg showed a mild effect in carrageenan-induced edema and moderate inhibition of paw swelling against developing arthritis. Although the combination of boswellic acids and glucosamine did not affect the acute inflammation to a greater extent yet a significant anti-arthritic activity was observed in rats. In conclusion, a synergistic effect was observed in chronic inflammatory conditions when two chemical entities were administered in combination in preclinical study. 相似文献
912.
Navidpour L Shadnia H Shafaroodi H Amini M Dehpour AR Shafiee A 《Bioorganic & medicinal chemistry》2007,15(5):1976-1982
A new type of 1-aryl-5-(4-methylsulfonylphenyl)imidazoles, possessing C-2 alkylthio (SMe or SEt) substituents, were designed and synthesized for evaluation as selective cyclooxygenase-2 (COX-2) inhibitors with in vivo anti-inflammatory activity. The compound, 1-(4-bromophenyl)-5-(4-methylsulfonylphenyl)-2-methylthioimidazole (11g), was the most potent and selective COX-2 inhibitor (COX-2 IC50=0.43 microM with no inhibition of COX-1 up to 25 microM) relative to the reference drug celecoxib (COX-2 IC50=0.21 microM with no inhibition of COX-1 up to 25 microM) and also showed very good anti-inflammatory activity compared to celecoxib in carrageenan-induced rat paw edema assay. 相似文献
913.
Haematological characterization of loach Misgurnus anguillicaudatus: comparison among diploid, triploid and tetraploid specimens 总被引:1,自引:0,他引:1
Gao Z Wang W Abbas K Zhou X Yang Y Diana JS Wang H Wang H Li Y Sun Y 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2007,147(4):1001-1008
The purpose of this study was to determine whether diploid, triploid and tetraploid loach (Misgurnus anguillicaudatus) differed in terms of their main haematological and physiological characteristics. Diploid and tetraploid fish were produced by crossing of natural diploids (2n x 2n) and natural tetraploids (4n x 4n), respectively. Triploid fish were produced by hybridization between diploid males and tetraploid females. The blood cells were significantly larger in polyploids, and the volumetric ratios of erythrocytes and leucocytes (thrombocyte and neutrophil) in tetraploids, triploids and diploids were consistent with the ploidy level ratio of 4:3:2. No significant differences were observed in haematocrit among polyploids. The erythrocyte count decreased with increased ploidy level, while total haemoglobin, mean cell volume, mean cellular haemoglobin content, and mean cell haemoglobin concentration all increased with increase in ploidy level. Erythrocyte osmotic brittleness declined in polyploids so that polyploid erythrocytes were more resistant to osmotic stress than diploid ones. Overall, loach with higher ploidy levels showed evidence of some advantages in haematological characteristics. 相似文献
914.
The regulation of transporters by nutrient-responsive signaling pathways allows cells to tailor nutrient uptake to environmental conditions. We investigated the role of feedback generated by transporter regulation in the budding yeast phosphate-responsive signal transduction (PHO) pathway. Cells starved for phosphate activate feedback loops that regulate high- and low-affinity phosphate transport. We determined that positive feedback is generated by PHO pathway-dependent upregulation of Spl2, a negative regulator of low-affinity phosphate uptake. The interplay of positive and negative feedback loops leads to bistability in phosphate transporter usage--individual cells express predominantly either low- or high-affinity transporters, both of which can yield similar phosphate uptake capacity. Cells lacking the high-affinity transporter, and associated negative feedback, exhibit phenotypes that arise from hysteresis due to unopposed positive feedback. In wild-type cells, population heterogeneity generated by feedback loops may provide a strategy for anticipating changes in environmental phosphate levels. 相似文献
915.
PreS domain of Hepatitis B virus (HBV) surface antigen is a good candidate for an effective vaccine as it activates both B and T cells besides binding to hepatocytes. This report deals with overexpression and purification of adr subtype of surface antigen that is more prevalent in Pakistan. PreS region, comprising 119 aa preS1 region plus a 55 aa preS2 region plus 11 aa from the N-terminal S region, was inserted in pET21a+ vector, cloned in E. coli DH5alpha cells and expressed in E. coli BL21 codon+ cells. The conditions for over expression were optimized using different concentrations of IPTG (0.01-5 mM), and incubating the cells at different temperatures (23-41 degrees C) for different durations (0-6 h). The cells were grown under the given optimized conditions (0.5 mM IPTG concentration at 37 degrees C for 4 h), lysed by sonication and the protein was purified by ion exchange chromatography. On the average, 24.5 mg of recombinant protein was purified per liter of culture. The purified protein was later lyophilized and stored at -80 degrees. 相似文献
916.
Coolen MJ Abbas B van Bleijswijk J Hopmans EC Kuypers MM Wakeham SG Sinninghe Damsté JS 《Environmental microbiology》2007,9(4):1001-1016
Within the upper 400 m at western, central and eastern stations in the world's largest stratified basin, the Black Sea, we studied the qualitative and quantitative distribution of putative nitrifying Archaea based on their genetic markers (16S rDNA, amoA encoding for the alpha-subunit of archaeal ammonia monooxygenase), and crenarchaeol, the specific glycerol diphytanyl glycerol tetraether of pelagic Crenarchaeota within the Group I.1a. Marine Crenarchaeota were the most abundant Archaea (up to 98% of the total archaeal 16S rDNA copies) in the suboxic layers with oxygen levels as low as 1 microM including layers where previously anammox bacteria were described. Different marine crenarchaeotal phylotypes (both 16S rDNA and amoA) were found at the upper part of the suboxic zone as compared with the base of the suboxic zone and the upper 15-30 m of the anoxic waters with prevailing sulfide concentrations of up to 30 microM. Crenarchaeol concentrations were higher in the sulfidic chemocline as compared with the suboxic zone. These results indicate an abundance of putative nitrifying Archaea at very low oxygen levels within the Black Sea and might form an important source of nitrite for the anammox reaction. 相似文献
917.
918.
Guinn BA Gilkes AF Woodward E Westwood NB Mufti GJ Linch D Burnett AK Mills KI 《Biochemical and biophysical research communications》2005,333(3):703-713
Acute myeloid leukaemia (AML) is a difficult to treat disease, especially for those patients who have no eligible haematopoietic stem cell (HSC) donor. One of the most promising treatment options for these patients is immunotherapy. To investigate the expression of known tumour antigens in AML, we analysed microarray data from 124 presentation AML patient samples and investigated the present/absent calls of 82 tumour-specific or -associated antigens. We found 11 antigens which were expressed in AML patient samples but not normal donors. Nine of these were cancer-testis (CT) antigens, previously shown to be expressed in tumour cells and immunologically protected sites and at very low levels, if at all, in normal tissues. Expression was confirmed using real-time PCR. We have identified a number of CT antigens with expression in presentation AML samples but not normal donor samples, which may provide effective targets for future immunotherapy treatments early in disease. 相似文献
919.
Attallah AM Abdel Aziz MM Abbas AT Elbakry KA El-Sharabasy MM 《Journal of helminthology》2004,78(3):189-194
A 30 kDa antigen was characterized as a hydrophobic polypeptide containing 16 amino acids and evaluated as a potential candidate vaccine against infection by Schistosoma mansoni. CD1 albino mice immunized at 0, 14, and 21 days with 25 or 50 microg of the 30 kDa antigen per mouse with and without alum developed high levels of IgG antibodies (predominantly IgG2a and IgG2b isotypes). When immunized mice were infected with 200 S. mansoni cercariae, the highest protection levels (61% and 65% reduction in worm burden in two separate experiments) were obtained using the 50-microg antigen without alum adjuvant. The granuloma size decreased to 10%, a non-significant level in mice immunized using alum adjuvant. The results demonstrate the ability of the 30 kDa antigen with and without alum adjuvant to protect mice against S. mansoni infection. 相似文献
920.
Role of B7 in T cell tolerance 总被引:7,自引:0,他引:7
Lohr J Knoechel B Kahn EC Abbas AK 《Journal of immunology (Baltimore, Md. : 1950)》2004,173(8):5028-5035
The induction of effective immune responses requires costimulation by B7 molecules, and Ag recognition without B7 is thought to result in no response or tolerance. We compared T cell responses in vivo to the same Ag presented either by mature dendritic cells (DCs) or as self, in the presence or absence of B7. We show that Ag presentation by mature B7-1/2-deficient DCs fails to elicit an effector T cell response but does not induce tolerance. In contrast, using a newly developed adoptive transfer system, we show that naive OVA-specific DO11 CD4+ T cells become anergic upon encounter with a soluble form of OVA, in the presence or absence of B7. However, tolerance in DO11 cells transferred into soluble OVA transgenic recipients can be broken by immunization with Ag-pulsed DCs only in B7-deficient mice and not in wild-type mice, suggesting a role of B7 in maintaining tolerance in the presence of strong immunogenic signals. Comparing two double-transgenic models--expressing either a soluble or a tissue Ag--we further show that B7 is not only essential for the active induction of regulatory T cells in the thymus, but also for their maintenance in the periphery. Thus, the obligatory role of B7 molecules paradoxically is to promote effective T cell priming and contain effector responses when self-Ags are presented as foreign. 相似文献