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901.
In silico modulation of HMGN-1 binding to histones and gene expression by interplay of phosphorylation and O-GlcNAc modification 总被引:1,自引:0,他引:1
Ahmad I Khan TS Hoessli DC Walker-Nasir E Kaleem A Shakoori AR Nasir-ud-Din 《Protein and peptide letters》2008,15(2):193-199
Utilizing different computational methods; phosphorylation, O-GlcNAc modification and Yin Yang sites are predicted in HMGN-1. Prediction results suggest that interplay of phosphorylation and O-GlcNAc modification regulates binding and removal of HMGN-1 with the nucleosome and its translocation from nucleus to cytoplasm and back to nucleus, consequently modulating gene expression. 相似文献
902.
Ahmad I Fatima I Afza N Malik A Lodhi MA Choudhary MI 《Journal of enzyme inhibition and medicinal chemistry》2008,23(6):918-921
Phytochemical investigations on the alkaloidal fraction of the whole plant of the Isatis tinctoria led to the isolation of the alkaloids 1-6., 3'-Hydroxyepiglucoisatisin (3), Epiglucoisatisin (2) were found to be potent urease inhibitors in a concentration-dependent manner with IC(50) values 25.63 +/- 0.74, 37.01 +/- 0.41 and 31.72 +/- 0.93, 47.33 +/- 0.31 microM against Bacillus pasteurii & Jack bean urease, respectively. Compounds 3 and 2 also showed potent inhibitory potential against alpha-chymotrypsin with IC(50) values of 23.40 +/- 0.21 and 27.45 +/- 0.23 microM, respectively. 相似文献
903.
Maharvi GM Ali S Riaz N Afza N Malik A Ashraf M Iqbal L Lateef M 《Journal of enzyme inhibition and medicinal chemistry》2008,23(1):62-69
A mild and efficient route to tetraketones (2-22) has been developed by way of tetraethyl ammonium bromide (Et(4)N(+)Br(- )) mediated condensation of dimedone (5,5-dimethylcyclohexane-1,3-dione, 1) with a variety of aldehydes. All these compounds showed significant lipoxygenase inhibitory activity and moderate to strong antioxidant potential. Compounds 19 (IC(50) = 7.8 microM), 22 (IC(50) = 12.5 microM), 3 (IC(50) = 16.3 microM), 11 (IC(50) = 17.5 microM) and 8 (IC(50) = 21.3 microM) showed significant inhibitory potential against lipoxygenase (baicalein, IC(50) = 22.4 microM). On the other hand compound 19 (IC(50) = 33.6 microM) also showed strong antioxidant activity compared to the standard (IC(50) = 44.7 microM). This study is likely to lead to the discovery of therapeutically efficient agents against very important disorders including inflammation, asthma, cancer and autoimmune diseases. 相似文献
904.
A two‐channel flow‐injection (FI) method is reported for the determination of iodide and iodine by its enhancement effect on the Ru(bpy)33+–NADH chemiluminescence (CL) system. The limit of detection (3 s of blank) was 1.0 × 10–9 mol/L iodide/iodine, with a sample throughput of 60/h. The calibration graphs over the range 1.0–50 × 10–8 mol/L gave correlation coefficients of 0.9994 and 0.999 (n = 5) with relative standard deviations (RSD; n = 4) of 1.0–2.5%, respectively. The effects of interfering cations, anions and some organic compounds were also studied. The method was applied to iodized salts and pharmaceutical samples and the results obtained were in good agreement with the value quoted. The CL method developed was compared with spectrophotometric method. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
905.
906.
Ahmad I Qazi WM Khurshid A Ahmad M Hoessli DC Khawaja I Choudhary MI Shakoori AR;Nasir-ud-Din 《Proteomics》2008,8(10):1954-1958
Post-translational modification (PTM) of a protein is an important event in regulating cellular functions. An algorithm, MAPRes, has been developed for mining associations among PTM sites and the preferred amino acids in their vicinity. The algorithm has been implemented to O-glycosylation and O-phosphorylation data (phosphorylated/glycosylated Ser/Thr/Tyr). The association patterns mined by MAPRes demonstrate significant correlations and the results are in conformity with the existing methods. These association rules/patterns will be helpful in predicting the sequences/motifs involved for specific PTMs in proteins. 相似文献
907.
The backwater system of Kerala is well known. In the present investigation, we have tried to explore the marine fungal diversity of selected backwater and brackish water habitats of the North Malabar region of Kerala, India. A total of 30 marine fungi were isolated, which include 19 Ascomycetes, 1 Basidiomycete, and 10 Mitosporic fungi. Periconia prolifica emerged as the most dominant one in terms of percent frequency of occurrence and percent relative abundance. 相似文献
908.
The competitiveness of online algorithms is measured based on the correctness of the results produced and processing time
efficiency. Traditionally evolutionary algorithms are not favored in online paradigms because of the large number of iterations
involved in the algorithm which translates directly into processing time overhead. In this paper we describe MARS (Management
Architecture for Resource Services) online scheduling algorithm which uses Simulated Annealing and concepts from Tabu Search
to drastically decrease the processing time of the algorithm. The paper outlines the concepts behind MARS, the components
involved and scheduling methodology used. In addition we also identify the time consuming bottlenecks in the performance of
the system and how evolutionary algorithms help us soar past them.
相似文献
Hesham El-RewiniEmail: |
909.
910.
H. Abdul Aziz A. Di Stefano L.M. Foresi F.J. Hilgen S.M. Iaccarino K.F. Kuiper F. Lirer G. Salvatorini E. Turco 《Palaeogeography, Palaeoclimatology, Palaeoecology》2008,257(1-2):123-138
An integrated magneto-biostratigraphic framework is presented for Middle Miocene sediments of DSDP Site 372 located in the Western Mediterranean. Detailed biostratigraphic analysis shows a nearly complete sequence of early Middle Miocene calcareous plankton bioevents in the Mediterranean, including the LCO (Last Common Occurrence) of the nannofossil Sphenolithus heteromorphus which has been astronomically dated in the Ras il Pellegrin (RIP) section on Malta Island [Abels, H.A., Hilgen, F.J., Krijgsman, W., Kruk, R.W., Raffi, I., Turco, E., Zachariasse, W.J., 2005. Long-period orbital control on middle Miocene global cooling: integrated stratigraphy and astronomical tuning of the Blue Clay Formation on Malta, Paleoceanography, 20, PA4012. doi: 10.1029/2004PA001129. 11 pp]. Thermal demagnetization of discrete samples revealed a characteristic low-temperature component with dual polarities despite a weak paleomagnetic signal. The resultant magnetostratigraphic record, combined with the calcareous plankton biostratigraphy, is straightforwardly correlated to the geomagnetic polarity time scale (CK95) of Cande and Kent [Cande, S.C., Kent, D.V., 1995. Revised calibration of the Geomagnetic Polarity Time Scale for the Late Cretaceous and Cenozoic, J. Geophys. Res., 100, 6093–6095] and the Astronomical Tuned Neogene Time Scale (ATNTS04) of Lourens et al. [Lourens, L.J., Hilgen, F.J., Laskar, J., Shackleton, N.J., Wilson, D., 2004. The Neogene Period. In: Gradstein F.M., Ogg J.G., Smith A.G. (Eds.), A Geologic Time Scale, Cambridge Univ. Press, pp. 409–440]. The subchrons recorded in Site 372 succession range from C5Br up to C5AAr. To confirm the magnetostratigraphic calibration, 40Ar/39Ar dating was performed on feldspar of two volcanic ash layers. The radio-isotopic dating indicates a younger age for these two ash layers compared to the magnetostratigraphic calibrated ages according to the CK95 and ATNTS04 age models. However, if the astronomically calibrated age of 28.21 ± 0.04 Ma is used for the Fish Canyon standard (FCs), the age for the older ash layer exactly matches its ATNTS04 age. Ages for bioevents were calculated assuming constant sedimentation rates between magnetostratigraphic age-tie points. The S. heteromorphus LCO has an age of 13.54 Ma and 13.63 Ma according to CK95 and ATNTS04, respectively, which is consistent with the astronomical tuned age of 13.65 Ma determined at RIP section [Abels, H.A., Hilgen, F.J., Krijgsman, W., Kruk, R.W., Raffi, I., Turco, E., Zachariasse, W.J., 2005. Long-period orbital control on middle Miocene global cooling: integrated stratigraphy and astronomical tuning of the Blue Clay Formation on Malta, Paleoceanography, 20, PA4012. doi:10.1029/2004PA001129. 11 pp]. We therefore conclude that the magnetostratigraphic calibration of DSDP Site 372 is correct and that, for the time being, this site can be considered as a reference section for the early Middle Miocene of the Mediterranean region. 相似文献