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21.
Galectins are mammalian lectins established to play a crucial role in the progression of various cancer types by the virtue of their differential expression in normal and cancerous cells. In the present study, goat heart galectin-1 (GHG-1) was purified and investigated for its potential role in the detection of post-malignant changes in glycosylation pattern. When exposed to superoxide radicals generated from a pyrogallol auto-oxidation system, GHG-1 treated erythrocyte suspension released higher amount of oxyhemoglobin than the unagglutinated erythrocytes. The extent of erythrocyte hemolysis was found to be directly proportional to concentrations of hypochlorous acid. GHG-1 was used to detect the change in the β-galactoside expression pattern in erythrocyte membrane from human donors suffering from prostate and breast cancer. No significant change was observed in the hemolysis of lectin agglutinated erythrocytes collected from pre-operated breast cancer patients, whereas significant increase was observed in normal healthy control and post-operated samples. Findings of this study proclaim GHG-1 as an important tool for the detection of post-malignant changes in glycosylation pattern.Abbreviations: Gal-1, galectin-1; GHG-1, goat heart galectin-1; HOCl, hypochlorous acid; OxyHb, oxyhemoglobin  相似文献   
22.
Stress has many biological effects on human daily life. In the present study, dietary protein intake was correlated with the investigated stress levels of nurses and housewives of the targeted urban population. Age group ranged from 30 to 45 years and both the groups belonged to middle socioeconomic status. After calculations of environmental, psychological and physiological stresses, it was observed that the levels of stress in housewives were significantly higher than those of nurses. Recommended dietary allowances, RDA and actual protein intakes, API were also compared in both the groups. The found protein intake was less in housewives as compared to that of nurses.  相似文献   
23.
The biotransformation potential of cell suspension cultures generated from Withania somnifera leaf was investigated, using withanolides, i.e. withanolide A, withaferin A, and withanone as precursor substrates. Interestingly, the cell suspension cultures showed inter-conversion of withanolides, as well converted to some unknown compounds, released to the culture media. The bio-catalyzed withanolide was detected and quantified by TLC and HPLC, respectively. There is noticeable conversion of withanolide A to withanone, and vice versa though at a lower level. The type of reaction of this biotransformation appears to be substitution of 20-OH group to 17-OH in withanolide A. In this paper, we present for the first time the possibility of biotransformation by inter-conversion of withanolides of pharmacological importance through cell suspension culture of W. somnifera. The possible role of putative cytochrome P450 hydroxylases is implicated in the conversion.  相似文献   
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A series of 2,4-diaryl-2,3,4,5-tetrahydro- (36-40) and 2,4-diaryl-2,3-dihydro-1,5-benzothiazepines (25-35) have been synthesized from the corresponding chalcones 1-24. Both the benzothiazepines and chalcones were evaluated as DPPH free-radical scavengers and as inhibitors of cholinesterases, urease, and alpha-glucosidase. Compounds 2, 5, 6, 7, 10, 13, 18, 21, 36a, 37a, 37b, and 39a showed significant cholinesterase inhibiting activities. Among the 15 dihydro-1,5-benzothiazepines, 26, 32, and 35 exhibited significant radical-scavenging activities; and six tetrahydro-1,5-benzothiazepines (35, 36a, 36b, 37a, 37b, and 39a) were found to be inhibitors of AChE and BChE. Compounds 22, 25, 26, 33, 35, 36a, 37b, and 39a inhibited urease, and 25 and 27-31 were found to be potent inhibitors of alpha-glucosidase.  相似文献   
26.
In vitro-grown shoots and calli of Withania somnifera, an important medicinal plant, were exposed to various types of salts under in vitro culture conditions. Membrane permeability, lipid peroxidation, and the antioxidant system increased in shoots as well as in unorganized callus tissues under all the three concentrations of KCl, NaCl, KNO3, NaNO3, and CaCl2. The growth responses of shoots and callus cultures under various salt treatments revealed that the tissue could grow better under NaCl and KNO3 compared to other salts and the in vitro shoots appeared healthy at 50?mM concentration of NaCl and KNO3. The activity of antioxidant enzymes such as catalase (CAT), ascorbate peroxidase, guaiacol peroxidase, lipoxygenase, polyphenol oxidase, and glutathione reductase increased under salt treatments, especially at higher concentrations. The greatest activity increase was recorded for peroxidases, whereas CAT was the least responsive. Only two isoforms, Mn-superoxide dismutase (Mn-SOD) and Fe-SOD, could be visualized in callus tissue while Cu/Zn-SOD was absent. Diaphorase 4 was totally missing in callus tissue and was detected only in shoots. Phenolics accumulated at all the concentrations of the salts tested as an induced protective response. The higher concentration of CaCl2 produced maximum increases in antioxidants and enzymatic activities compared to other salts. Thus, for W. somnifera the presence of excess calcium in the growing medium is most deleterious compared to other salts. Results also suggest that the nonenzymatic and enzymatic antioxidant systems of both the tissues played a primary role in combating the imposed salt stress.  相似文献   
27.
To uncover the molecular mechanisms of embryonic development, the ideal loss-of-function strategy would be capable of targeting specific regions of the living embryo with both temporal and spatial precision. To this end, we have developed a novel pharmacological agent that can be light activated to achieve spatiotemporally limited inhibition of Rho kinase activity in vivo. A new photolabile caging group, 6-nitropiperonyloxymethyl (NPOM), was installed on a small-molecule inhibitor of Rho kinase, Rockout, to generate a 'caged Rockout' derivative. Complementary biochemical, cellular, molecular and morphogenetic assays in both mammalian cell culture and Xenopus laevis embryos validate that the inhibitory activity of the caged compound is dependent on exposure to light. Conveniently, this unique reagent retains many of the practical advantages of conventional small-molecule inhibitors, including delivery by simple diffusion in the growth medium and concentration-dependent tuneability, but can be locally activated by decaging with standard instrumentation. Application of this novel tool to the spatially heterogeneous problem of embryonic left-right asymmetry revealed a differential requirement for Rho signaling on the left and right sides of the primitive gut tube, yielding new insight into the molecular mechanisms that generate asymmetric organ morphology. As many aromatic/heterocyclic small-molecule inhibitors are amenable to installation of this caging group, our results indicate that photocaging pharmacological inhibitors might be a generalizable technique for engendering convenient loss-of-function reagents with great potential for wide application in developmental biology.  相似文献   
28.
In colorectal cancer (CRC), chromosomal instability (CIN) is typically studied using comparative-genomic hybridization (CGH) arrays. We studied paired (tumor and surrounding healthy) fresh frozen tissue from 86 CRC patients using Illumina's Infinium-based SNP array. This method allowed us to study CIN in CRC, with simultaneous analysis of copy number (CN) and B-allele frequency (BAF)--a representation of allelic composition. These data helped us to detect mono-allelic and bi-allelic amplifications/deletion, copy neutral loss of heterozygosity, and levels of mosaicism for mixed cell populations, some of which can not be assessed with other methods that do not measure BAF. We identified associations between CN abnormalities and different CRC phenotypes (histological diagnosis, location, tumor grade, stage, MSI and presence of lymph node metastasis). We showed commonalities between regions of CN change observed in CRC and the regions reported in previous studies of other solid cancers (e.g. amplifications of 20q, 13q, 8q, 5p and deletions of 18q, 17p and 8p). From Therapeutic Target Database, we identified relevant drugs, targeted to the genes located in these regions with CN changes, approved or in trials for other cancers and common diseases. These drugs may be considered for future therapeutic trials in CRC, based on personalized cytogenetic diagnosis. We also found many regions, harboring genes, which are not currently targeted by any relevant drugs that may be considered for future drug discovery studies. Our study shows the application of high density SNP arrays for cytogenetic study in CRC and its potential utility for personalized treatment.  相似文献   
29.
In vitro multiple shoots, root, callus and cell suspension cultures of Withania somnifera exhibited the potentiality to produce pharmacologically active withanolides. Multiple shoots cultures exhibited an increase in withanolide A accumulation compared to shoots of the mother plant. In vitro generated root cultures as well as callus and suspension cultures also produced withanolides albeit at lower levels.  相似文献   
30.
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