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761.
Ajit Sadana 《Biotechnology letters》1979,1(11):465-470
A pH-dependent deactivation model is developed for immobilized and soluble enzymes in which the rate of enzyme decay is assumed proportional to the concentration of theactive enzyme. The model developed applies reasonably well to pH-stability data of Johnson and coworkers (1977 a,b,c; 1978 a,b,c). 相似文献
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Journal of Plant Research - In-vitro studies of the ontogeny and mating system of the gametophytes of Lepisorus nudus were carried out through multispore and isolate cultures lasting... 相似文献
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Suresh Kumar Ajay Kumar Anup Singh Pathania Santosh Kumar Guru Srinivas Jada Parduman Raj Sharma Shashi Bhushan Ajit Kumar Saxena H. M. Sampath Kumar Fayaz Malik 《Apoptosis : an international journal on programmed cell death》2013,18(5):605-617
This study describes the mechanism of trolox and tiron induced potentiation of cytotoxicity caused by Ery5, an analog of magnolol, in human myeloid leukemia HL-60 cells. Ery5 induced cytotoxicity in HL-60 cells by involving activation of bax and cleavage of caspase 3, which contributed towards activation of both apoptotic and autophagic pathways. Trolox and tiron, even at non-toxic concentrations, contributed to the cytotoxicity of Ery5 by activation of autophagic proteins like ATG7, ATG12 and LC3-II. Z-VAD-fmk mediated reduction in the cytotoxicity and expression of autophagic proteins, further suggested that autophagy induced by Ery5 is largely dependent upon caspases. Interestingly, Ery5 induced autophagy was accompanied by the downregulation of PI3K/AKT pathway whereas, trolox and tiron strongly enhanced this effect. In addition to that treatment of cells with Ery5, trolox and tiron individually, displayed a marked upregulation of Bax. The involvement of Bax in trolox and tiron induced enhancement of the cytotoxicity of Ery5 was confirmed, when siRNA induced silencing of Bax led to increased viability of the cells and exerted a strong inhibitory effect on LC3-II accumulation and p62 degradation in case of cells treated by the combination of Ery5 with trolox or tiron. Additionally, an important role of PARP in Ery5 mediated cell death has been suggested by PARP silencing experiments, however, potentiation of autophagic cytotoxicity by trolox and tiron did not seem to be dependent on PARP-1. Therefore, Bax seems to play a vital role in trolox and tiron mediated potentiation of autophagic cell death by Ery5 in HL-60 cells. 相似文献
767.
The root endophytic fungus Piriformospora indica is a prime candidate to improve the growth and yield of plants. It also acts as a growth promoter and bioprotector, as well
as combating environmental stress in a range of plant species. In the present investigation impact of a P. indica culture filtrate was studied on Helianthus annus Sun gold and H. annus Japanese gold varieties in the greenhouse. Treatment with the P. indica culture filtrate promoted overall growth and seed production of the plants. Moreover, the oil content of the seeds increased
by 50% to 70% in these two varieties of H. annus plants. The possible reasons for these effects are discussed. 相似文献
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Dinesh Kumar Jangid Anjali Guleria Dinesh C. Gautam Hemendra Yadav Manas Mathur Ajit Kumar Swami 《Nucleosides, nucleotides & nucleic acids》2019,38(8):533-549
The current research article involves one pot synthesis of novel substituted 1-nitro-10H-phenothiazines via Smiles rearrangement. These substituted phenothiazines undergo oxidation to yield 10H-phenothiazine-5,5-dioxides (sulfones) while on treatment with β-D-ribofuranose-1-acetate-2,3,5-tribenzoate yield ribofuranosides. These compounds were screened for their antimicrobial vitalities (in vitro) against selected strains of bacteria and fungi. The characterization of synthesized compounds was done by elemental and spectral studies. 相似文献
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Ajit P. Rokhade Namdev B. Shelke Sangamesh A. Patil Tejraj M. Aminabhavi 《Carbohydrate polymers》2007,69(4):678-687
Interpenetrating polymer network (IPN) microspheres of chitosan (CS) and methylcellulose (MC) were prepared by emulsion-crosslinking in the presence of glutaraldehyde (GA) as a crosslinker. Theophylline (THP), an antiasthmatic drug was encapsulated into IPN microspheres under varying ratios of MC and CS, % drug loading and amount of GA added. IPNs have shown better mechanical properties than pure CS. Cross-link density of the matrices was significantly affected by the amount of GA and MC. Microspheres were characterized by Fourier transform infrared (FTIR) spectroscopy to assess the formation of IPN structure and to confirm the absence of chemical interactions between drug, polymer and crosslinking agent. Particle size was measured by laser light scattering technique. Microspheres with the average particle sizes ranging from 119 to 318 μm were produced. Differential scanning calorimetry (DSC) and X-ray diffraction (X-RD) studies were performed to understand the crystalline nature of drug after encapsulation into IPN microspheres. Theophylline encapsulation of up to 82% was achieved as measured by UV spectrometer. Equilibrium swelling was performed in distilled water. In vitro release studies were performed in both 0.1 N HCl and pH 7.4 buffer solutions. These data indicated a dependence of drug release on the extent of crosslinking and amount of MC added during the preparation of microspheres. The release was extended up to 12 h and release rates were fitted to an empirical equation to compute the diffusional parameters, which indicated a slight deviation from the Fickian trend for the release of theophylline. 相似文献
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