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51.
Homocysteine thiolactone (HCTL) is a cyclic thioester of homocysteine, showing high reactivity toward lysine residues of proteins.
In the present study the structural properties and aggregation propensity of bovine pancreatic insulin were studied in the
presences of increasing concentration of HCTL (0–500 μM), using different spectroscopic techniques. As shown in this study,
HCTL induces gross structural alterations and subsequently aggregation of insulin in a dose dependent manner. Also induction
of insulin aggregation by HCTL occurs in a sequential process, where native protein with alpha-helical abundant structure
gradually transforms into partially folded conformations with the significant amount of beta-sheet. Since C-terminal B-chain
of insulin plays a critical role in stability of this protein, the structural alteration/aggregation induced by HCTL can be
consequence of homocysteinylation of the only Lysine residue (Lys29) on its B-chain. This study may have important implications
regarding the effect of HCTL on structure of insulin particularly in the pathological states linked to hyperhomocysteinemia. 相似文献
52.
Rahimi AA Gee K Mishra S Lim W Kumar A 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(12):7823-7832
IL-10, an anti-inflammatory cytokine, has been shown to exhibit stimulatory functions including CD14 up-regulation on human monocytic cells. CD14-mediated signaling following LPS stimulation of monocytic cells results in the synthesis of proinflammatory cytokines. Our results show that LPS-induced CD14 expression on monocytic cells may be mediated by endogenously produced IL-10. To investigate the molecular mechanism by which IL-10 enhances CD14 expression, both human monocytes and the promyelocytic HL-60 cells were used as model systems. IL-10 induced the phosphorylation of PI3K and p42/44 ERK MAPK. By using specific inhibitors for PI3K (LY294002) and ERK MAPKs (PD98059), we demonstrate that LY294002 either alone or in conjunction with PD98059 inhibited IL-10-induced phosphorylation of STAT-1 and consequently CD14 expression. However, IL-10-induced STAT-3 phosphorylation remained unaffected under these conditions. Finally, STAT-1 interfering RNA inhibited IL-10-induced CD14 expression. Taken together, these results suggest that IL-10-induced CD14 up-regulation in human monocytic cells may be mediated by STAT-1 activation through the activation of PI3K either alone or in concert with the ERK MAPK. 相似文献
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54.
Seyed Jafar Mousavy Gholam Hossein Riazi Mahmood Kamarei Hadi Aliakbarian Naghmeh Sattarahmady Ahmad Sharifizadeh Shahrokh Safarian Faizan Ahmad Ali Akbar Moosavi–Movahedi 《International journal of biological macromolecules》2009,44(3):278-285
Widespread use of mobile phones has increased the human exposure to electromagnetic fields (EMFs). It is required to investigate the effect of EMFs on the biological systems. In this paper the effect of mobile phone RF (910 MHz and 940 MHz) on structure and function of HbA was investigated. Oxygen affinity was measured by sodium dithionite with UV–vis spectrophotometer. Structural changes were studied by circular dichroism and fluorescence spectroscopy. The results indicated that mobile phone EMFs altered oxygen affinity and tertiary structure of HbA. Furthermore, the decrease of oxygen affinity of HbA corresponded to the EMFs intensity and time of exposure. 相似文献
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56.
Leveillula on monocotyledonous plants have been recorded as L. taurica by several authors, whereas the fungus on Allium has been described as an independent species, namely L. allii, by some authors. We sequenced ca 600 bp of the rDNA ITS region for two Leveillula specimens from Allium and Polianthes (both from monocotyledons) and compared them with several already published sequences from Leveillula isolates from dicotyledons. Pair-wise percentages of sequence divergences were calculated for all Leveillula isolates. The ITS sequence of the Polianthes isolate was identical to L. taurica on Helianthus and Vicia. The sequence of the Allium isolate was 99.5 % identical to L. taurica on Euphorbia, Haplophylum, Peganum, etc. These results suggest close relationships between monocot and dicot pathogenic Leveillula species. The identity between two monocot isolates was 98.4 %. Phylogenetic analysis revealed that the two monocot isolates do not group into a clade together. This result suggests that Leveillula acquired parasitism to monocots at least twice independently. 相似文献
57.
Mehdi Adib Fariba Peytam Reihaneh Shourgeshty Maryam Mohammadi-Khanaposhtani Mehdi Jahani Somaye Imanparast Mohammad Ali Faramarzi Bagher Larijani Ali Akbar Moghadamnia Ensieh Nasli Esfahani Fatemeh Bandarian Mohammad Mahdavi 《Bioorganic & medicinal chemistry letters》2019,29(5):713-718
Twenty three fused carbazole–imidazoles 6a–w were designed, synthesized, and screened as new α-glucosidase inhibitors. All the synthesized fused carbazole-imidazoles 6a-w were found to be more active than acarbose (IC50?=?750.0?±?1.5?µM) against yeast α-glucosidase with IC50 values in the range of 74.0?±?0.7–298.3?±?0.9?µM. Kinetic study of the most potent compound 6v demonstrated that this compound is a competitive inhibitor for α-glucosidase (Ki value?=?75?µM). Furthermore, the in silico studies of the most potent compounds 6v and 6o confirmed that these compounds interacted with the key residues in the active site of α-glucosidase. 相似文献
58.
This investigation was carried on to find out the changes occurred in Stevia rebaudiana in response to paclobutrazol (PBZ; 0–4 mg L?1) treatment and drought stress. Polyethylene glycol (PEG; 0–6 % w/v) was used to stimulate drought stress. Drought stress reduced fresh and dry weight, water content, chlorophylls, carotenoids, anthocyanins, water soluble carbohydrates, reducing sugar and proline amounts. Electrolyte leakage, MDA, α-tocopherol and glycine betaine contents increased in drought-stressed plants. The activity of P5CS and PDH enzymes and protein content showed no significant changes under drought stress. PBZ (with or without PEG) treatments decreased fresh and dry weight and water content. In PBZ-treated plants, less pigments was damaged by drought stress. PBZ treatment reduced the negative effect of drought stress on lipid peroxidation which resulted in lower electrolyte leakage and MDA content, compared to the same PEG level without PBZ. PBZ (with or without PEG) treatments increased glycine betaine, α-tocopherol, proline and protein contents. The amount of water soluble carbohydrates, reducing sugar and activity of P5CS and PDH were not affected by PBZ treatments. SDS-PAGE analysis revealed that drought stress increased a 25 kD protein with a critical function in plant development under stresses. According to the results, PEG provoked a severe drought stress in S. rebaudiana that could partly be restored by PBZ treatment. 相似文献
59.
Javed Muhammad Umar Javaid Nadeem Malik Muhammad Waseem Akbar Mariam Samuel Omaji Yahaya Adamu Sani Othman Jalel Ben 《Cluster computing》2022,25(3):1839-1867
Cluster Computing - In this study, a secure and coordinated blockchain based energy trading system for Electric Vehicles (EVs) is presented. The major goals of this study are to provide secure and... 相似文献
60.