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11.
K Srikanth T Murugesan Ch Anil Kumar V Suba A K Das S Sinha G Arunachalam L Manikandan 《Phytomedicine》2002,9(1):75-77
The effect of methanol extract of whole plants of Trichodesma indicum R. Br. has been investigated on sulphur dioxide (SO2) induced cough reflex in Swiss albino mice. The extract has demonstrated significant (p < 0.001) inhibition in frequency of cough in all the tested doses when compared with untreated control group. The effect persisted up to 90 min of its oral administration and also comparable to that of the effect exhibited by the standard drug (Codeine phosphate). This study confirmed the traditional use of this plant in the treatment of cough. Determination of underlying mechanism of beneficial effect is major topic requiring further comprehensive investigation. 相似文献
12.
A combined approach to data mining of textual and structured data to identify cancer-related targets
Background
We present an effective, rapid, systematic data mining approach for identifying genes or proteins related to a particular interest. A selected combination of programs exploring PubMed abstracts, universal gene/protein databases (UniProt, InterPro, NCBI Entrez), and state-of-the-art pathway knowledge bases (LSGraph and Ingenuity Pathway Analysis) was assembled to distinguish enzymes with hydrolytic activities that are expressed in the extracellular space of cancer cells. Proteins were identified with respect to six types of cancer occurring in the prostate, breast, lung, colon, ovary, and pancreas. 相似文献13.
Bubb MR Govindasamy L Yarmola EG Vorobiev SM Almo SC Somasundaram T Chapman MS Agbandje-McKenna M McKenna R 《The Journal of biological chemistry》2002,277(23):20999-21006
An antiparallel actin dimer has been proposed to be an intermediate species during actin filament nucleation. We now show that latrunculin A, a marine natural product that inhibits actin polymerization, arrests polylysine-induced nucleation at the level of an antiparallel dimer, resulting in its accumulation. These dimers, when composed of pyrene-labeled actin subunits, give rise to a fluorescent excimer, permitting detection during polymerization in vitro. We report the crystallographic structure of the polylysine-actin-latrunculin A complex at 3.5-A resolution. The non-crystallographic contact is consistent with a dimeric structure and confirms the antiparallel orientation of its subunits. The crystallographic contacts reveal that the mobile DNase I binding loop of one subunit of a symmetry-related antiparallel actin dimer is partially stabilized in the interface between the two subunits of a second antiparallel dimer. These results provide a potential explanation for the paradoxical nucleation of actin filaments that have exclusively parallel subunits by a dimer containing antiparallel subunits. 相似文献
14.
Arunachalam J Kanagasabai V Gautham N 《Biochemical and biophysical research communications》2006,342(2):424-433
We combine a new, extremely fast technique to generate a library of low energy structures of an oligopeptide (by using mutually orthogonal Latin squares to sample its conformational space) with a genetic algorithm to predict protein structures. The protein sequence is divided into oligopeptides, and a structure library is generated for each. These libraries are used in a newly defined mutation operator that, together with variation, crossover, and diversity operators, is used in a modified genetic algorithm to make the prediction. Application to five small proteins has yielded near native structures. 相似文献
15.
Antimicrobial, cytolytic, and cell-penetrating peptides induce pores or perturbations in phospholipid membranes that result in fluxes of dyes into or out of lipid vesicles. Here we examine the fluxes induced by four of these membrane-active peptides in giant unilamellar vesicles. The type of flux is determined from the modality of the distributions of vesicles as a function of their dye content using the statistical Hartigan dip test. Graded and all-or-none fluxes correspond to unimodal and bimodal distributions, respectively. To understand how these distributions arise, we perform Monte Carlo simulations of peptide-induced dye flux into vesicles using a very simple model. The modality of the distributions depends on the rate constants of pore opening and closing, and dye flux. If the rate constants of pore opening and closing are both much smaller than that of dye flux through the pore, all-or-none influx occurs. However, if one of them, especially the rate constant for pore opening, increases significantly relative to the flux rate constant, the process becomes graded. In the experiments, we find that the flux type is the same in giant and large vesicles, for all peptides except one. But this one exception indicates that the flux type cannot be used to unambiguously predict the mechanism of membrane permeabilization by the peptides. 相似文献
16.
R. N. Parthasarathy J. Lakshmanan M. Thangavel R. S. Seelan J. I. Stagner A. J. Janckila R. E. Vadnal M. F. Casanova L. K. Parthasarathy 《Molecular and cellular biochemistry》2013,378(1-2):83-89
The therapeutic effects of lithium in bipolar disorder are poorly understood. Lithium decreases free inositol levels by inhibiting inositol monophosphatase 1 and myo-inositol 3-phosphate synthase (IPS). In this study, we demonstrate for the first time that IPS can be phosphorylated. This was evident when purified rat IPS was dephosphorylated by lambda protein phosphatase and analyzed by phospho-specific ProQ-Diamond staining and Western blot analysis. These techniques demonstrated a mobility shift consistent with IPS being phosphorylated. Mass spectral analysis revealed that Serine-524 (S524), which resides in the hinge region derived from exon 11 of the gene, is the site for phosphorylation. Further, an antibody generated against a synthetic peptide of IPS containing monophosphorylated-S524, was able to discriminate the phosphorylated and non-phosphorylated forms of IPS. The phosphoprotein is found in the brain and testis, but not in the intestine. The intestinal IPS isoform lacks the peptide bearing S524, and hence, cannot be phosphorylated. Evidences suggest that IPS is monophosphorylated at S524 and that the removal of this phosphate does not alter its enzymatic activity. These observations suggest a novel function for IPS in brain and other tissues. Future studies should resolve the functional role of phospho-IPS in brain inositol signaling. 相似文献
17.
Lakshmanan Venkatachalam R. V. Sreedhar Neelwarne Bhagyalakshmi 《Plant Growth Regulation》2007,51(3):193-205
Use of high levels of growth regulators during micropropagation results in undesirable clonal variability in important commercial
crops such as banana. The present study investigated the effects of high levels of cytokinins on micropropagation in banana
(genotype AAB), and the genetic stability of plantlets was assessed using RAPD and ISSR markers. Cytokinins, such as BA and
kinetin were added to the routine shoot multiplication medium at concentrations up to 10 mg l−1. After 12 weeks of culture involving three subcultures, the maximum number of shoot buds were produced in cultures receiving
either 5 mg l−1 BA (80 shoot buds) or 4 mg l−1 kinetin (62 shoot buds). Certain morphological abnormalities observed during proliferation of shoot buds in vitro were not
observed during acclimatization ex vitro. To check the genetic stability, RAPD and ISSR profiles of micropropagated plantlets
obtained from different cytokinin-treatments were compared with control microplants maintained on MS medium as well as the
field-grown mother plant. A total of 50 RAPD and 12 ISSR primers resulted in 625 distinct and reproducible bands. Thus a total
of 17,400 bands were generated showing homogeneous RAPD and ISSR patterns. Band intensity histogram of each gel confirmed
their monomorphic nature with no genetic variation in all the plantlets analysed. Based on these results a protocol for high
rate shoot multiplication was worked out leading to uniform shoot production. 相似文献
18.
Haining Li Bihua Xia Wei Chen Yumeng Zhang Xia Gao Arunachalam Chinnathambi Sulaiman A. Alharbi Yujie Zhao 《Journal of biochemical and molecular toxicology》2020,34(9)
The current work planned to assess the protecting properties of nimbolide against doxorubicin (DOX)‐treated myocardial damage. Myocardial damage was produced with 2.5 mg/kg of DOX given on alternative days (14 days). Thiobarbituric acid reactive substances (TBARS) levels of a lipid peroxidative marker were elevated, whereas reduced body weight, heart weight, blood pressure indices and reduced levels of antioxidants like glutathione‐S‐transferase, superoxide dismutase, catalase, glutathione peroxidase, glutathione, and glutathione reductase were observed in the heart tissue of DOX‐treated animals. DOX‐treated animals showed augmented levels of cardiac markers likes monocyte chemotactic protein‐1, interferon‐gamma, aspartate transferase, creatine kinase, lactate dehydrogenase, creatine kinase‐muscle/brain, heart‐type fatty acid‐binding protein, glycogen phosphorylase isoenzyme BB, transforming growth factor‐β, brain natriuretic peptide, myoglobin, and cTnI in serum. Histopathological assessment confirmed the DOX‐induced cardiotoxicity. Furthermore, DOX‐induced rats showed augmented inflammatory mediators (nuclear factor‐κB [NF‐kB], tumor necrosis factor‐α [TNF‐α], and interleukin‐1β [IL‐1β]) and increased PI3K/Akt signaling proteins (PI3K, p‐Bad/Bad, caspase‐3, and p‐Akt), whereas decreased oxidative markers (HO‐1 and NQO‐1) and p‐PTEN were observed. Nimbolide‐supplemented rats showed reduced activity/levels of cardiac markers and TBARS levels in serum and heart tissue. Levels of enzymatic and nonenzymatic antioxidants were augmented in the heart tissue of nimbolide‐supplemented rats. Nimbolide influence decreased apoptosis, inflammation, and enhanced antioxidant markers through the modulation of p‐Bad/Bad, caspase‐3, PI3K, p‐Akt, TNF‐α, NF‐kB, IL‐1β, HO‐1, NQO‐1, and p‐PTEN markers. The histopathological explanations were observed to be in line with biochemical analysis. Therefore, the finding of current work was that nimbolide has a defensive effect on the myocardium against DOX‐induced cardiac tissue damage. 相似文献
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