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81.
82.
Peptide-based therapies offer the potential for non-genotoxic, genotype-specific alternatives, or adjuvants, to the current range of traditional cancer treatments. Such a patient-tailored cancer-cell-directed therapeutic approach should have fewer side effects and could well be more effective than the current drug- or combination-based regimens. Here, we review the potential of novel natural anticancer peptides such as necrotic peptides, apoptotic peptides, function-blocking peptides, antiangiogenic peptides and immunostimulatory peptides in the context of their ability to induce tumor regression. We focus on the therapeutic prospects of anticancer peptides and their possible application in tumor therapy. 相似文献
83.
Ghosh K Chandra K Roy SK Mondal S Maiti D Das D Ojha AK Islam SS 《Carbohydrate research》2008,343(2):341-349
A water-soluble polysaccharide was isolated from the aqueous extract of the stem of Lagenaria siceraria. The polysaccharide was found to be constituted of methyl d-galacturonate, 2-O-methyl-D-xylose, and d-xylose in a ratio of 1:1:1. On the basis of total acid hydrolysis, methylation analysis, periodate oxidation, NMR studies ((1)H, (13)C, 2D-COSY, TOCSY, NOESY, HSQC, and HMBC), and MALDI-TOF MS analysis, the structure of the repeating unit of the polysaccharide is determined as. 相似文献
84.
Loop length and its composition are important for the structural and functional versatility of quadruplexes. To date studies on the loops have mainly concerned model sequences compared with naturally occurring quadruplex sequences which have diverse loop lengths and compositions. Herein, we have characterized 36 quadruplex-forming sequences from the promoter regions of various proto-oncogenes using CD, UV and native gel electrophoresis. We examined folding topologies and determined the thermodynamic profile for quadruplexes varying in total loop length (5–18 bases) and composition. We found that naturally occurring quadruplexes have variable thermodynamic stabilities (ΔG37) ranging from −1.7 to −15.6 kcal/mol. Overall, our results suggest that both loop length and its composition affect quadruplex structure and thermodynamics, thus making it difficult to draw generalized correlations between loop length and thermodynamic stability. Additionally, we compared the thermodynamic stability of quadruplexes and their respective duplexes to understand quadruplex–duplex competition. Our findings invoke a discussion on whether biological function is associated with quadruplexes with lower thermodynamic stability which undergo facile formation and disruption, or by quadruplexes with high thermodynamic stability. 相似文献
85.
The effect of loop length on quadruplex stability has been studied when the G-rich strand is present along with its complementary C-rich strand, thereby resulting in competition between quadruplex and duplex structures. Using model sequences with loop lengths varying from T to T5, we carried out extensive FRET to discover the influence of loop length on the quadruplex-Watson Crick duplex competition. The binding data show an increase in the binding affinity of quadruplexes towards their complementary strands upon increasing the loop length. Our kinetic data reveal that unfolding of the quadruplex in presence of a complementary strand involves a contribution from a predominant slow and a small population of fast opening conformer. The contribution from the fast opening conformer increases upon increasing the loop length leading to faster duplex formation. FCS data show an increase in the interconversion between the quadruplex conformers in presence of the complementary strand, which shifts the equilibrium towards the fast opening conformer with an increase in loop length. The relative free-energy difference (Delta DeltaG(o)) between the duplex and quadruplex indicates that an increase in loop length favors duplex formation and out competes the quadruplex. 相似文献
86.
Hutchings KM Tran TP Ellsworth EL Watson BM Sanchez JP Hollis Showalter HD Stier MA Shapiro M Themis Joannides E Huband M Nguyen DQ Maiti S Li T Tailor J Thomas G Ha C Singh R 《Bioorganic & medicinal chemistry letters》2008,18(18):5087-5090
A novel series of bacterial topoisomerase (3-aminoquinazolinediones) inhibitors are described. The side-chain SAR against Gram-positive and Gram-negative organisms as well as DNA gyrase activity is reported. 相似文献
87.
Decolorization and purification of crude protease from Rhizopus oryzae by activated charcoal and its electrophoretic analysis 总被引:1,自引:0,他引:1
Kaustav Aikat Tapas Kumar Maiti Bimal Chandra Bhattacharyya 《Biotechnology letters》2001,23(4):295-301
Activated charcoal decolorized and partially purified the protease from a crude extract of solid state fermentation of wheat bran by Rhizopus oryzae. Treatment for 5 min was sufficient. Depending on the initial colour intensity of crude, the charcoal to crude extract ratio could be optimized to achieve 90% decolorization, 85% enzyme recovery, and over a 3-fold purification, even up to 20-fold variation in batch size (from 1 ml to 20 ml crude extract). Decolorization followed the Freundlich and the Langmuir models, the Freundlich constant, n, being 2.74. Partial purification was confirmed by native PAGE and the protease band identified by gelatin-PAGE. SDS-PAGE showed the protease consisted of two sub-units (about 22 and 24 kDa).
List of symbols:
c
o, initial solute concentration in liquid before adsorption; c
*, equilibrium solute concentration in liquid after adsorption; k, empirical constant for Freundlich adsorption isotherm; U, unit of protease activity; v, volume of solution per unit weight of adsorbent. 相似文献
88.
Primula munroi的产自东喜马拉雅的一个新亚种——P. munroi ssp. schizocalyx 总被引:1,自引:0,他引:1
Sandip Kumar Basak Gour Gopal Maiti 《植物分类学报》2001,39(5):473-476
InthecourseofrevisingthegenusPrimulaLinn .(Primulaceae)intheHimalayasofIndianre gion ,theauthorscameacrossasetofcollectionsidentifiedasP .involucrataWall.gatheredbythepioneerHimalayantravellers,merelywrittenondeterminavitslipsasP .involucrataWall.formaschiz… 相似文献
89.
Methanol extract of Strychnos potatorum Linn. seeds (SPSE) was evaluated for its diuretic activity in Wistar albino rats. The SPSE was administered at the graded doses of 200, 400, and 600 mg/kg body weight. The parameters which were taken into account during the experimental on each rat were: total urine volume (corrected for water intake during the test period), body weight before and after the experiment, and the concentration of sodium, potassium, and chloride ions in urine. The total urine volumes of the SPSE (600 mg/kg)-treated rats were evaluated nearly two and half fold then compared with the control (saline treated) group. Excretion of cations (sodium and potassium ions) and anions (chloride ions) also increased significantly with respect to the control group. The diuretic effect was comparable with that of the standard drug Furosemide. The increase of cations in the urine on treatment with Strychnos potatorum seed extract (SPSE) was dose-dependent. This effect supports the use of the Strychnos potatorum seeds as a diuretic in folk remedies. 相似文献
90.
Bahare Shokoohian Babak Negahdari Hamidreza Aboulkheyr Es Manuchehr Abedi-Valugerdi Kaveh Baghaei Tarun Agarwal Tapas Kumar Maiti Moustapha Hassan Mustapha Najimi Massoud Vosough 《Journal of cellular and molecular medicine》2021,25(18):8602-8614
Hepatocellular carcinoma (HCC), the most common type of liver cancer, is usually a latent and asymptomatic malignancy caused by different aetiologies, which is a result of various aberrant molecular heterogeneity and often diagnosed at advanced stages. The incidence and prevalence have significantly increased because of sedentary lifestyle, diabetes, chronic infection with hepatotropic viruses and exposure to aflatoxins. Due to advanced intra- or extrahepatic metastasis, recurrence is very common even after radical resection. In this paper, we highlighted novel therapeutic modalities, such as molecular-targeted therapies, targeted radionuclide therapies and epigenetic modification-based therapies. These topics are trending headlines and their combination with cell-based immunotherapies, and gene therapy has provided promising prospects for the future of HCC treatment. Moreover, a comprehensive overview of current and advanced therapeutic approaches is discussed and the advantages and limitations of each strategy are described. Finally, very recent and approved novel combined therapies and their promising results in HCC treatment have been introduced. 相似文献