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41.
《Cell reports》2020,30(5):1530-1541.e4
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42.
Tomohiko J. Itoh Hidemi Sato 《Biochimica et Biophysica Acta (BBA)/General Subjects》1984,800(1):21-27
The initial rate and final extent of polymerization of both bovine brain tubulin and sea urchin egg tubulin were enhanced in the presence of 2H2O. The yields were increased in association with the elevation of the 2H2O concentration. 2H2O also reduced the critical concentration for polymerization of brain tubulin. Thermodynamic analysis was attempted using the temperature dependence of the critical concentration for polymerization in the presence of 2H2O. We obtained linear van 't Hoff plots and calculated thermodynamic parameters which were positive and were increased with the elevation of the 2H2O concentration. The enhancement of the polymerization of tubulin by 2H2O could, therefore, be the result of the strenghening of intra-and/or inter-molecular hydrophobic interactions of the tubulin molecules. We believe that the increase in lenghth and number of microtubules of the mitotic spindles in the dividing cells of the eukaryotes with 2H2O may be caused by the direct involvement of 2H2O in the polymerization of tubulin. 相似文献
43.
An examination of four species of Cirsium disclosed the presence of two new flavonoids in C. lineare. The structure of one was 5,4′-dihydroxy-6,7,3′-trimethoxyflavone (cirsilineol) 4′-monoglucoside and the other 5,3′,4′-trihydroxy-6,7-dimethoxyflavone (cirsiliol) 4′-monoglucoside. Luteolin 7-glucoside was found in C. suffultum, and pectolinarin and linarin in C. kamtschaticum and C. pectinellum. 相似文献
44.
Lina Long Douglas R. McCabe M. Eileen Dolan 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1999,731(2):128
A highly sensitive and selective method for determining 8-oxoguanine in plasma and urine was developed by high-performance liquid chromatography with electrochemical detection. The compound was separated by gradient elution on a C18 reversed-phase column with a mobile phase of acetonitrile and 0.1 M sodium acetate, pH 5.2. 8-Hydroxy-2′-deoxyguanosine was used as internal standard. 8-Oxoguanine was detected electrochemically by setting the potential to +300 mV vs. Pd reference. The sensitivity of the assay was 22 ng/ml with a signal-to-noise ratio of 7:1. The within-day relative standard deviations for 8-oxoguanine quality control samples with concentrations of 3340, 1340 and 84 ng/ml were 3.6, 4.3 and 5.7% for plasma, and 4.1, 4.6 and 6.2% for urine, respectively. The day-to-day relative standard deviations for the same samples were 3.8, 6.8 and 7.1% for plasma, and 3.9, 7.0 and 7.9% for urine, respectively. The method is designed to study the pharmacokinetics and metabolic fate of O6-benzylguanine in a phase I clinical trial. Previously, O6-benzyl-8-oxoguanine was identified as the primary metabolite of O6-benzylguanine in humans. We now demonstrate that 8-oxoguanine is a further metabolite of O6-benzylguanine. 相似文献
45.
ANATH BANDHU DAS ARUP KUMAR MUKHERJEE PREMANANDA DAS 《Botanical journal of the Linnean Society. Linnean Society of London》2001,136(2):221-229
Random amplified polymorphic DNA (RAPD) markers are used to estimate interspecific variation among mangrove and non-mangrove Heritiera fomes, H. littoralis and H. macrophylla. All the species have 2n = 38 chromosomes, with minute structural changes distinguishing the karyotype of each species. Significant variation of 4C DNA content occurs at the interspecific level. Interspecific polymorphism ranged from 14.09% between H. fomes and H. littoralis to 52.73% between H. fomes and H. macrophylla. H. macrophylla showed wide polymorphism in the RAPD marker with H. littoralis (51.23%) and H. fomes (52.73%). Two distinct RAPD products obtained from OPA-10 (1000 bp) and OPD-15 (900 bp) found characteristic molecular markers in H. macrophylla , a species from a non-mangrove habitat. H. macrophylla was more distantly related to H. fomes [genetic distance (1-F) = 0.305] than to H. littoralis [genetic distance (1-F) = 0.273]. H. littoralis was of a closer affinity to H. fomes [genetic distance (1-F) = 0.218] than to H. macrophylla. 相似文献
46.
Rashi Verma Monika Yadav Rajabrata Bhuyan Shweta Aggarwal Arnab Nayek 《Journal of receptor and signal transduction research》2016,36(6):601-616
Computer-aided antibody engineering has been successful in the design of new biologics for disease diagnosis and therapeutic interventions. Interleukin-6 (IL-6), a well-recognized drug target for various autoimmune and inflammatory diseases such as rheumatoid arthritis, multiple sclerosis, and psoriasis, was investigated in silico to design potential lead antibodies. Here, crystal structure of IL-6 along with monoclonal antibody olokizumab was explored to predict antigen–antibody (Ag???Ab)-interacting residues using DiscoTope, Paratome, and PyMOL. Tyr56, Tyr103 in heavy chain and Gly30, Ile31 in light chain of olokizumab were mutated with residues Ser, Thr, Tyr, Trp, and Phe. A set of 899 mutant macromolecules were designed, and binding affinity of these macromolecules to IL-6 was evaluated through Ag???Ab docking (ZDOCK, ClusPro, and Rosetta server), binding free-energy calculations using Molecular Mechanics/Poisson Boltzman Surface Area (MM/PBSA) method, and interaction energy estimation. In comparison to olokizumab, eight newly designed theoretical antibodies demonstrated better result in all assessments. Therefore, these newly designed macromolecules were proposed as potential lead antibodies to serve as a therapeutics option for IL-6-mediated diseases. 相似文献
47.
48.
Miranda Kleijn Harry O. Voorma Adri A. M. Thomas 《Journal of cellular biochemistry》1995,59(4):443-452
Mitogenic stimulation of protein synthesis is accompanied by an increase in elF-4E phosphorylation. The effect on protein synthesis by induction of differentiation is less well known. We treated P19 embryonal carcinoma cells with the differentiating agent retinoic acid and found that protein synthesis increased during the first hour of addition. However, the phosphorylation state, as well as the turnover of phosphate on elF-4E, remained unchanged. Apparently, the change in protein synthesis after RA addition is regulated by another mechanism than elF-4E phosphorylation. By using P19 cells overexpressing the EGF receptor, we show that the signal transduction pathway that leads to phosphorylation of elF-4E is present in P19 cells; the EGF-induced change in phosphorylation of elF-4E in these cells is likely to be regulated by a change in elF-4E phosphatase activity. These results suggest that the onset of retinoic acid-induced differentiation is triggered by a signal transduction pathway which involves changes in protein synthesis, but not elF-4E phosphorylation. © 1995 Wiley-Liss, Inc. 相似文献
49.
An Ecteola-cellulose chromatography assay for 3′-phosphoadenosine 5′-phosphosulfate: Phenol sulfotransferase 总被引:1,自引:0,他引:1
Ronald T. Borchardt Anna Baranczyk-Kuzma Carol L. Pinnick 《Analytical biochemistry》1983,130(2):334-338
A new assay procedure for phenol sulfotransferase which employs [35S]-3'-phosphoadenosine-5'-phosphosulfate as a sulfate donor and a variety of phenols as sulfate acceptors was developed. The appearance of the 35S-sulfated products or the disappearance of the [35S]-3'-phosphoadenosine-5'-phosphosulfate are determined simultaneously by chromatography of the assay incubation mixtures on Ecteola-cellulose columns, eluting with an NH4HCO3 step gradient. Various acidic, neutral, and basic phenols can be employed as substrates for phenol sulfotransferase using this procedure. 相似文献
50.
《Peptides》2016
Metformin, α-glucosidase inhibitors (α-GIs), and dipeptidyl peptidase 4 inhibitors (DPP-4Is) reduce hyperglycemia without excessive insulin secretion, and enhance postprandial plasma concentration of glucagon-like peptide-1 (GLP-1) in type-2 diabetes mellitus (T2DM) patients. We assessed add-on therapeutic effects of DPP-4I anagliptin in Japanese T2DM patients treated with metformin, an α-GI miglitol, or both drugs on postprandial responses of GLP-1 and glucose-dependent insulinotropic polypeptide (GIP), and on plasma concentration of the appetite-suppressing hormone leptin. Forty-two Japanese T2DM patients with inadequately controlled disease (HbA1c: 6.5%–8.0%) treated with metformin (n = 14), miglitol (n = 14) or a combination of the two drugs (n = 14) received additional treatment with anagliptin (100 mg, p.o., b.i.d.) for 52 weeks. We assessed glycemic control, postprandial responses of GLP-1 and glucose-dependent insulinotropic polypeptide (GIP), and on plasma concentration of leptin in those patients. Add-on therapy with anagliptin for 52 weeks improved glycemic control and increased the area under the curve of biologically active GLP-1 concentration without altering obesity indicators. Total GIP concentration at 52 weeks was reduced by add-on therapy in groups treated with miglitol compared with those treated with metformin. Add-on therapy reduced leptin concentrations. Add-on therapy with anagliptin in Japanese T2DM patients treated with metformin and miglitol for 52 weeks improved glycemic control and enhanced postprandial concentrations of active GLP-1/total GIP, and reduce the leptin concentration. 相似文献