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951.
Anti-inflammatory effect of the alcoholic extracts of N. sativa seeds and its callus on mix glial cells of rat with regard to their thymoquinone (TQ) content was investigated. Callus induction was achieved for explants of young leaf, stem, petiole, and root of N. sativa on solid Murashige and Skoog (MS) medium containing 2,4-D (1 mg/l) and kinetin (2.15 mg/l). TQ content of the alcoholic extracts was measured by HPLC. Total phenols were determined using Folin–Ciocalteu method and antioxidant power was estimated using FRAP tests. The mix glial cells, inflamed by lipopolysaccharide, were subjected to anti-inflammatory studies in the presence of various amounts of TQ and the alcoholic extracts. Viability of the cells and nitric oxide production were measured by MTT and Griess reagent, respectively. The leaf callus obtained the highest growth rate (115.4 mg/day) on MS medium containing 2,4-D (0.22 mg/l) and kinetin (2.15 mg/l). Analyses confirmed that TQ content of the callus of leaf was 12 times higher than that measured in the seeds extract. However, it decreased as the calli aged. Decrease in the TQ content of the callus was accompanied with an increase in its phenolic content and antioxidant ability. Studies on the inflamed rat mix glial cells revealed significant reduction in the nitric oxide production in the presence of 0.2 to 1.6 mg/ml of callus extract and 1.25 to 20 μl/ml of the seed extracts. However, the extent of the effects is modified assumingly due to the presence of the other existing substances in the extracts.  相似文献   
952.
Biodiversity information in available germplasm is very useful for the success of any breeding program. To establish genetic diversity among 44 genotypes of chickpea comprising cultigen, landraces, internationally developed improved lines and wild relatives, genetic distances were evaluated using 19 simple sequence repeat markers with 100 marker loci. Estimation of the number of alleles per locus (n a), the effective allele number (n e), and Wright fixation index F were 6.25, 3.67, and 0.44, respectively. Polymorphism information content values ranged from 0.84 (locus NCPGR6 and TA135) to 0.44 (locus NCPGR7) with an average of 0.68. Dice’s coefficient similarity matrix for studied chickpea genotypes varied from 0.07 to 1.0 indicating a broader genetic base among genotypes studied. The highest similarity, 1.0, was observed between genotypes Sel 96TH11484 and Sel 96TH11485; while, the lowest, 0.07, was observed between genotypes Sel 95TH1716 and Azad. Based on the UPGMA clustering method, all genotypes were clustered in eight groups, which indicated the probable origin and region similarity of landraces and local Iran landraces over the other cultivars and wild species. It also represents a wide diversity among available germplasm. Analysis of molecular variance revealed that 41% of the total variance was due to differences among groups while 59% was due to differences within groups. The results of principal coordinate analysis approximately corresponded to those obtained through cluster analysis. Genetic variation detected in this study can be useful for selective breeding for specific traits and in enhancing the genetic base of breeding programs.  相似文献   
953.
Acute kidney injury induces the loss of renal microvessels, but the fate of endothelial cells and the mechanism of potential vascular endothelial growth factor (VEGF)-mediated protection is unknown. Cumulative cell proliferation was analyzed in the kidney of Sprague-Dawley rats following ischemia-reperfusion (I/R) injury by repetitive administration of BrdU (twice daily) and colocalization in endothelial cells with CD31 or cablin. Proliferating endothelial cells were undetectable for up to 2 days following I/R and accounted for only ~1% of BrdU-positive cells after 7 days. VEGF-121 preserved vascular loss following I/R but did not affect proliferation of endothelial, perivascular cells or tubular cells. Endothelial mesenchymal transition states were identified by localizing endothelial markers (CD31, cablin, or infused tomato lectin) with the fibroblast marker S100A4. Such structures were prominent within 6 h and sustained for at least 7 days following I/R. A Tie-2-cre transgenic crossed with a yellow fluorescent protein (YFP) reporter mouse was used to trace the fate of endothelial cells and demonstrated interstititial expansion of YFP-positive cells colocalizing with S100A4 and smooth muscle actin following I/R. The interstitial expansion of YFP cells was attenuated by VEGF-121. Multiphoton imaging of transgenic mice revealed the alteration of YFP-positive vascular cells associated with blood vessels characterized by limited perfusion in vivo. Taken together, these data indicate that vascular dropout post-AKI results from endothelial phenotypic transition combined with an impaired regenerative capacity, which may contribute to progressive chronic kidney disease.  相似文献   
954.
This study investigated three lab-scale hybrid wetland systems with traditional (gravel) and alternative substrates (wood mulch and zeolite) for removing organic, inorganic pollutants and coliforms from a synthetic wastewater, in order to investigate the efficiency of alternative substrates, and monitor the stability of system performance. The hybrid systems were operated under controlled variations of hydraulic load (q, 0.3-0.9 m3/m2 d), influent ammoniacal nitrogen (NH4-N, 22.0-80.0 mg/L), total nitrogen (TN, 24.0-84.0 mg/L) and biodegradable organics concentration (BOD5, 14.5-102.0 mg/L). Overall, mulch and zeolite showed promising prospect as wetland substrates, as both media enhanced the removal of nitrogen and organics. Average NH4-N, TN and BOD5 removal percentages were over 99%, 72% and 97%, respectively, across all three systems, indicating stable removal performances regardless of variable operating conditions. Higher Escherichia coli removal efficiencies (99.9%) were observed across the three systems, probably due to dominancy of aerobic conditions in vertical wetland columns of the hybrid systems.  相似文献   
955.
A series of 30 organic chlacones and 33 ferrocenyl (Fc) chalcones were synthesized and characterized by melting point, elemental analysis, spectroscopy ((1)H NMR and FTIR) and, in two cases, by X-ray crystallography. The biological activity of each compound (10(-4)M in DMSO) against the model nematode Caenorhabditis elegans was examined in terms of % mortality (percent nematodes that died) and % fecundity (percent nematodes that reproduced) and compared to that obtained for the control medium (1% DMSO) over a 14-day period. Detailed conformational analyses for two Fc-chalcones (studied also by X-ray crystallography) were performed via molecular modeling studies. In general, the organic chalcones were found to be less polar than their Fc analogs. Some structure-activity relationships (SARs) were determined: (a) The nematocidal activities of the organic chalcones in this series were found to be much greater than those of their ferrocenyl analogs. (b) The position of the carbonyl group played a central role in the biological activity of both classes of chalcones studied. (c) For both classes of chalcones, lipophilicity of a compound seemed to play a significant role in its nematocidal activity. (d) The planarity of a ferrocenyl-chlacone seems to play a role in its activity.  相似文献   
956.
Series of chromone containing sulfonamides were prepared by the reaction of (un)substituted 3-formylchromones with 3-aminobenzenesulfonamide and 4-aminobenzenesulfonamide. Bovine carbonic anhydrase (bCA) inhibitory activity of these newly synthesized compounds was determined. All compounds were active and possessed excellent bCA inhibitory activities with IC?? values ranged between 4.31 ± 0.001 and 29.12 ± 0.008 μmol. Compounds derived from 6-fluoro-3-formylchromones were the most active.  相似文献   
957.
The anti-phytoplasma activities of surfactin (derived from Iranian native Bacillus subtilis isolates) and tetracycline towards Candidatus "Phytoplasma aurantifolia", the agent of lime Witches' broom disease, were investigated. HPLC was used to quantify the surfactin production in four previously characterized native surfactin-producing strains, and the one producing the highest amount of surfactin (about 1,500 mg/l) was selected and cultivated following optimized production and extraction protocols. Different combinations of purified surfactin and commercial tetracycline were injected into artificially phytoplasmainfected Mexican lime seedlings using a syringe injection system. An absolute quantitative real-time PCR system was developed to monitor the phytoplasma population shifts in the lime phloem during 3 months following the injections. The results revealed that the injections of surfactin or tetracycline had a significant inhibitory effect on Candidatus "P. aurantifolia". However, the combined treatment with both surfactin and tetracycline (1:1) resulted in the highest inhibition due to a synergic effect, which suppressed the phytoplasma population from about 2×10(5) to less than 10 phytoplasma units/g plant tissue.  相似文献   
958.
Transplantations of bone marrow-derived cells (BMDCs) are traditionally used for hematologic diseases, but there are increasing numbers of clinical trials using BMDC treatments for non-hematologic disorders, including autoimmune diseases. BMDCs are recently reported to improve organ functions. This paper will review available reports supporting the role of BMDCs in reducing xerostomia (i.e. re-establishing salivary gland functions) due to head and neck irradiation for cancer therapies and in Sj?gren's syndrome. There are reports that BMDCs provide a beneficial effect on the saliva production. BMDCs positively affect blood vessels stability and regeneration in irradiated salivary glands. Also, BMDCs provide an immunomodulatory activity in mice with Sj?gren's-like disease. While the exact mechanisms by which BMDCs improve organ functions remain controversial, there is preliminary evidence that a combination of them (such as cell transdifferentiation, vasculogenesis, and paracrine effect) occur in salivary glands.  相似文献   
959.
The focus of this investigation was to prepare the cocrystal of carbamazepine (CBZ) using nicotinamide as a coformer and to compare its preformulation properties and stability profile with CBZ. The cocrystal was prepared by solution cooling crystallization, solvent evaporation, and melting and cryomilling methods. They were characterized for solubility, intrinsic dissolution rate, chemical identification by Fourier transform infrared spectroscopy, crystallinity by differential scanning calorimetry, powder X-ray diffraction, and morphology by scanning electron microscopy. Additionally, mechanical properties were evaluated by tensile strength and Heckel analysis of compacts. The cocrystal and CBZ were stored at 40°C/94% RH, 40°C/75% RH, 25°C/60% RH, and 60°C to determine their stability behavior. The cocrystals were fluffy, with a needle-shaped crystal, and were less dense than CBZ. The solubility profiles of the cocrystals were similar to CBZ, but its intrinsic dissolution rate was lower due to the high tensile strength of its compacts. Unlike CBZ, the cocrystals were resistant to hydrate transformation, as revealed by the stability studies. Plastic deformation started at a higher compression pressure in the cocrystals than CBZ, as indicated by the high yield pressure. In conclusion, the preformulation profile of the cocrystals was similar to CBZ, except that it had an advantageous resistance to hydrate transformation.  相似文献   
960.
Cultivation of crops in soils with high salt (NaCl) content can affect plant development. We examined the morphological and physiological mechanisms of salt tolerance in tomato. The responses of 72 accessions of tomato (Solanum lycopersicum) to salinity were compared by measuring shoot and root lengths, and fresh shoot and root weights relative to those of controls (plants grown in normal salt levels). All traits were reduced at the seedling stage when salinity levels were increased. The accession x salinity interaction was significant for all traits. Root length had higher heritability than other traits and was used as a selection criterion to identify salt-tolerant and -non-tolerant accessions. On the basis of root length, accessions LA2661, CLN2498A, CLN1621L, BL1176, 6233, and 17870 were considered to be more tolerant than accessions 17902, LO2875 and LO4360. The degree of salt tolerance was checked by analyzing K+ and Na+ concentrations and K+/Na+ ratio in tissues of plants treated with 10 and 15 dS/m salinity levels. Tolerance of these accessions to salinity was most associated with low accumulation of Na+ and higher K+/Na+ ratios.  相似文献   
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